SORGHUM ENTOMOLOGY Progress Report-6

STUDIES ON MYTHIMNA SEPARATA AT ICRISAT

Progress Report 1980-81

HC Sharma VS Bhatnagar and JC Davies

4 ICRISAT

International Crops Research Institute for the Semi-Arid Tropics

ICRISAT Patancheru PO

Andhra Pradesh 502 324 India

1982

ACKNOWLEDGEMENTS

The assistance received from support staff of the sorghum

and cropping entomology is duely acknowledged The keen

interest and tireless efforts of Mr V Venkateswara Rao need

special mention Our thanks are also due to our co-operators

namely Drs F R Biddinger V Mahalakshmi B S Talukdar

S V R Shetty and M V Natarajan who willingly offered their

experiments to collect observations on various aspects and

for making available their own data for purposes of comparision

The encouragement received during the course of this work from

Dr L R House and Mr D J Andrews is gratefully acknowledged

The authors are also thankful to Drs K Leuschner W Reed

AB Mohamed R P Thakur and SL Taneja for going through the

manuscript and making valuable suggestions

STUDIES ON MYTHIMNA SEPARATA AT ICRIFAT

HC Sharma VS Bhatnagar and JC Davies

1 INTRODUCTION

The oriental armyworm Mythimna (Pseudaletia)(Leucania) separata

Walker is a pest of cereals in Asia and Australia between 450N

to 450 S latitude and 60 E to beyond 170 W longitude It has been

reported to feed in nature on 33 plant species and some unshy

specified grasses belonging to eight plant families (Sharma amp

Davies 1982) Prior to 1950 it was of minor importance in India

In the last two decades extensive damage has been reported from

over 25 places in different parts of India It has become a serious

pest on sorghum millets rice maize and wheat with the increase In

irrigated areas and the consequent changes in farming systems

introduction of high yielding varieties heavy fertilizer use and

continuous cultivation (Bindra and Singh 1973 Verma and Khurana

1971 and Gopinadhan and Kushwaha 1978)

At ICRISAT Center outbreak of Mythimna separata defoliating

sorghum and pearl-millet was recorded In 1977 Consequently the biology

and population dynamics of the pest has been studied and efforts made

2

2

to screen pearl millet and sorghum genotypes for resistance to this

pest The report covers the results of the studies carried out on

these and related aspects over the past several years at the ICRISAT

Center

INCIDENCE AND BIOLOGY

In the period 1977-79 Mythimna damage or larval population was recorded

by selecting 100 plants (at random) diagonally across sorghum and pearl

millet fields Usually a number of fields on two soil types (Alfisols

and Vertisols) were included in samples to determine the range of

infestation In 197 8 sampling was continuous throuyhout the year

Additional data from sole and intercropped sorghum (with pigeonpea)

were recorded in large intercropping trials between 1975 to 1980 In

these observations the number of larvae were recorded from 100 plants or

earheads

At ICRISAT Center Mythimna separata larvae severely damage pearl-millet

and sorghum during August-September (Tablel In alfisols pearl millet

sustained higher damage compared to sorghum Extensive defoliation was

observed during 1977 when its first outbreak occured

In intercropping trials upto 106 larvae100 plants were recorded

during 1977 (Table 2) The larval populations were considerable in

subsequent seasons though far less than that of 1977 Larvae were observed

in June 7-10 days after the first few showers of monsoon rains

3

The biology of the insect was studied during October 1979 and

January-February 1980 under ambient temperature and relative humidity

3 The moths obtained from the field collected larvae were kept in 30 cm

cages The moths were provided with 10 honey solution in a cotton

swab The eggs were laid on dry sorghum leaves or butter paper placed

at the bottom of the cage Larvae were fed on sorghum leaves in 1 ltr

plastic jars Data were recorded on the development of the various stadia

and on other biological aspects such as oviposition and sex ratio

The females laid an average of 996 eggs after a pre-oviposition

period of 2-5 days Oviposition continued for 2-7 days after emergence

(Table 3) Egg incubation took 4-5 days The larval instars I-VII

averaged 39 33 31 27 31 22 amp 18 days respectively Preshy

pupal and pupal periods lasted for 1-2 and 8-12 days respectively The

entire post-embryonic development was completed in 29-39 days A third

instar larva weighed on an average OlO-O15g and a pupa 026-042g

3 OUTBREAKS

Outbreaks of M separata occured at ICRISAT Center during 1977 1978

1980 Outbreaks at other locations have been recorded during 1980-81

at Dharwad and at Anantapur and Nandyal during 1981

Mythimna outbreaks have occured in India and elsewhere in many

seasons (Sharma amp Davies 1982) A basic knowledge of (a) temperature

and RH requirements of the insect in the ecosystem (b) availability

14

of suitable hosts (c)migration and (d)extent of parasitism and

parasites involved may help to understand the factors controlling

the insect population The outbreaks in India China Japan Bangladesh

New Zealand Fiji and Australia have been attributed to (a) the owqrrenc

of drought following rains (b) floods resulting from heavy rainfall

(c) Induction of migrant populations into a geographic area(d) heavy

fertilizer use (e) trash mulching and (f) temperature and humidity

regimes in the periods preceding and during the outbreaks (Butani 1955

Puttarudriah and Usrnan 1957 Chin 1979 Grist and Lever 1969 Avasthy

and Chaudhary 1965 and Koyama 1966) High rainfall possibly leads to

high humidity and more food which are very essential for survival and

development of the larvae Prolonged periods of drought following rains may

possibly restrict the activity of natural control agents (parasites

predators amp diseases) Heavy manuring leads to better crop growth for

insect feeding and development Trash mulching provides a good site

for oviposition and better place for the larvae to hide in

The factors resulting in outbreaks at ICRISAT Center and other

places are not fully understood The light traps have not Indicated

the arrival of migrant populations Moreover the phototropic behaviour

of migrant moths is not fully known Duelng 1977-78 the outbreaks

possibly resulted from drought preceded by a period of normal rainfall

while during 1980 the outbreak was preceded by a period of heavy rainfall

The build up of damaging populatlons at ICRISAT Center might have resulted

from lavish crop growth and heavy use of fertilizers Another factor

may be the low parasitism and disease levels (around 30) observed at

ICRISAT Center as against gt75 in Punjab and Rajasthan (Butter 1978

5

and Gopinadhan and Kushwaha 1978) due to Apanteles ruficrus and Bacillus

cereus respectively Anantapur experienced the first recorded outbreak

during 1981 It is a drought-prone area and unusually in that year normal

and well distributed rainfall was experienced The arrival of migrant

populations or build of native populations in the absence of parasites

might have led to population explosion A close examination of the case

histories of a number of outbreaks may help to elucidate the factor(s)

leadiny to opulation explosion

4 POPULATION DYNAMICS

41 ADULTS

Activity of adult Mythimna spV was monitored daily using light traps

(Bhatnagar and Davies 1979) installed at three locations at ICRISAT

Center The data were converted into 4 week moving means to allow for

moon phase effects (Bhatnagar and Davies 1978)

The site of one light trap (Site 1) on an alfisol which wa operated

continuously between Aug 1974 and July1979 was subsequently changed The

light traps at 3ite 2 (alfisol) and Site 3 (vertisol) were commissioned

In Sept 1975 and May 1977 respectively Light trap catches at ICRISAT

Cencer over the four ear period (1977-80) at three locations are given In

Table4 Most moths were caught durlng September but catches were high

recorded in the months from December-MayIn August Very few moths were

and no moths were attracted to light in June Catches of moths were

highest in 1977

6

The four week moving means of the trap catches are presented in

Figl The insect population as indicated by trap catches was lower

during 1974-76 and 1979-80 (Figl) The insect activity was higher during

August-September The trap catches were higher during 1977 when extensive

damage occured in sorghum and pearl-millet The trap catches differed

between locations (Fig2) The maximum number of moths were caught In the

trap located in the vertisol watersheds which is in the midst of a large

area planted to sorghum and maize The trap catches were considerably

lower in traps located at Manmool village (tnap surrounded by off-season

nursery area irrigated paddy fields and rainfed alfisols) Crop

Improvement Building and RA-l(near the Hyderabad-Bombay highway with trees

on one side and rainfed alfisols on the other)

The light trap catches temperature humidity and rainfall frnom 1976

to 1980 are presented in Fig3 The peak activity period moved ahead by

5-6 weeks from 1976 to 1980 The insect population appeared to follow the

changes in weather However no single factor exercised marked effect on

the insect populations Generally more moths were caught during periods

of low rainfall preceded by a 2-4 week period of normal rainfall During

1980 there was no distinct period of prolonged drought and the trap

catches declined with the decrease in the amount of rainfall The trap

catches during 1979 showed considerable insect activity up to November

when a bimodAl pattern of rainfall was experienced The insect population

was highest during 1977 when rainfall was low and erratic The maximum

activity period was also preceded by 4-5 weeks of moderate temperatures

(20-30C) higher humidity (50-95) and smaller differences between the

maximum and minimum temperatures and RH These conditions are highly

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

ACKNOWLEDGEMENTS

The assistance received from support staff of the sorghum

and cropping entomology is duely acknowledged The keen

interest and tireless efforts of Mr V Venkateswara Rao need

special mention Our thanks are also due to our co-operators

namely Drs F R Biddinger V Mahalakshmi B S Talukdar

S V R Shetty and M V Natarajan who willingly offered their

experiments to collect observations on various aspects and

for making available their own data for purposes of comparision

The encouragement received during the course of this work from

Dr L R House and Mr D J Andrews is gratefully acknowledged

The authors are also thankful to Drs K Leuschner W Reed

AB Mohamed R P Thakur and SL Taneja for going through the

manuscript and making valuable suggestions

STUDIES ON MYTHIMNA SEPARATA AT ICRIFAT

HC Sharma VS Bhatnagar and JC Davies

1 INTRODUCTION

The oriental armyworm Mythimna (Pseudaletia)(Leucania) separata

Walker is a pest of cereals in Asia and Australia between 450N

to 450 S latitude and 60 E to beyond 170 W longitude It has been

reported to feed in nature on 33 plant species and some unshy

specified grasses belonging to eight plant families (Sharma amp

Davies 1982) Prior to 1950 it was of minor importance in India

In the last two decades extensive damage has been reported from

over 25 places in different parts of India It has become a serious

pest on sorghum millets rice maize and wheat with the increase In

irrigated areas and the consequent changes in farming systems

introduction of high yielding varieties heavy fertilizer use and

continuous cultivation (Bindra and Singh 1973 Verma and Khurana

1971 and Gopinadhan and Kushwaha 1978)

At ICRISAT Center outbreak of Mythimna separata defoliating

sorghum and pearl-millet was recorded In 1977 Consequently the biology

and population dynamics of the pest has been studied and efforts made

2

2

to screen pearl millet and sorghum genotypes for resistance to this

pest The report covers the results of the studies carried out on

these and related aspects over the past several years at the ICRISAT

Center

INCIDENCE AND BIOLOGY

In the period 1977-79 Mythimna damage or larval population was recorded

by selecting 100 plants (at random) diagonally across sorghum and pearl

millet fields Usually a number of fields on two soil types (Alfisols

and Vertisols) were included in samples to determine the range of

infestation In 197 8 sampling was continuous throuyhout the year

Additional data from sole and intercropped sorghum (with pigeonpea)

were recorded in large intercropping trials between 1975 to 1980 In

these observations the number of larvae were recorded from 100 plants or

earheads

At ICRISAT Center Mythimna separata larvae severely damage pearl-millet

and sorghum during August-September (Tablel In alfisols pearl millet

sustained higher damage compared to sorghum Extensive defoliation was

observed during 1977 when its first outbreak occured

In intercropping trials upto 106 larvae100 plants were recorded

during 1977 (Table 2) The larval populations were considerable in

subsequent seasons though far less than that of 1977 Larvae were observed

in June 7-10 days after the first few showers of monsoon rains

3

The biology of the insect was studied during October 1979 and

January-February 1980 under ambient temperature and relative humidity

3 The moths obtained from the field collected larvae were kept in 30 cm

cages The moths were provided with 10 honey solution in a cotton

swab The eggs were laid on dry sorghum leaves or butter paper placed

at the bottom of the cage Larvae were fed on sorghum leaves in 1 ltr

plastic jars Data were recorded on the development of the various stadia

and on other biological aspects such as oviposition and sex ratio

The females laid an average of 996 eggs after a pre-oviposition

period of 2-5 days Oviposition continued for 2-7 days after emergence

(Table 3) Egg incubation took 4-5 days The larval instars I-VII

averaged 39 33 31 27 31 22 amp 18 days respectively Preshy

pupal and pupal periods lasted for 1-2 and 8-12 days respectively The

entire post-embryonic development was completed in 29-39 days A third

instar larva weighed on an average OlO-O15g and a pupa 026-042g

3 OUTBREAKS

Outbreaks of M separata occured at ICRISAT Center during 1977 1978

1980 Outbreaks at other locations have been recorded during 1980-81

at Dharwad and at Anantapur and Nandyal during 1981

Mythimna outbreaks have occured in India and elsewhere in many

seasons (Sharma amp Davies 1982) A basic knowledge of (a) temperature

and RH requirements of the insect in the ecosystem (b) availability

14

of suitable hosts (c)migration and (d)extent of parasitism and

parasites involved may help to understand the factors controlling

the insect population The outbreaks in India China Japan Bangladesh

New Zealand Fiji and Australia have been attributed to (a) the owqrrenc

of drought following rains (b) floods resulting from heavy rainfall

(c) Induction of migrant populations into a geographic area(d) heavy

fertilizer use (e) trash mulching and (f) temperature and humidity

regimes in the periods preceding and during the outbreaks (Butani 1955

Puttarudriah and Usrnan 1957 Chin 1979 Grist and Lever 1969 Avasthy

and Chaudhary 1965 and Koyama 1966) High rainfall possibly leads to

high humidity and more food which are very essential for survival and

development of the larvae Prolonged periods of drought following rains may

possibly restrict the activity of natural control agents (parasites

predators amp diseases) Heavy manuring leads to better crop growth for

insect feeding and development Trash mulching provides a good site

for oviposition and better place for the larvae to hide in

The factors resulting in outbreaks at ICRISAT Center and other

places are not fully understood The light traps have not Indicated

the arrival of migrant populations Moreover the phototropic behaviour

of migrant moths is not fully known Duelng 1977-78 the outbreaks

possibly resulted from drought preceded by a period of normal rainfall

while during 1980 the outbreak was preceded by a period of heavy rainfall

The build up of damaging populatlons at ICRISAT Center might have resulted

from lavish crop growth and heavy use of fertilizers Another factor

may be the low parasitism and disease levels (around 30) observed at

ICRISAT Center as against gt75 in Punjab and Rajasthan (Butter 1978

5

and Gopinadhan and Kushwaha 1978) due to Apanteles ruficrus and Bacillus

cereus respectively Anantapur experienced the first recorded outbreak

during 1981 It is a drought-prone area and unusually in that year normal

and well distributed rainfall was experienced The arrival of migrant

populations or build of native populations in the absence of parasites

might have led to population explosion A close examination of the case

histories of a number of outbreaks may help to elucidate the factor(s)

leadiny to opulation explosion

4 POPULATION DYNAMICS

41 ADULTS

Activity of adult Mythimna spV was monitored daily using light traps

(Bhatnagar and Davies 1979) installed at three locations at ICRISAT

Center The data were converted into 4 week moving means to allow for

moon phase effects (Bhatnagar and Davies 1978)

The site of one light trap (Site 1) on an alfisol which wa operated

continuously between Aug 1974 and July1979 was subsequently changed The

light traps at 3ite 2 (alfisol) and Site 3 (vertisol) were commissioned

In Sept 1975 and May 1977 respectively Light trap catches at ICRISAT

Cencer over the four ear period (1977-80) at three locations are given In

Table4 Most moths were caught durlng September but catches were high

recorded in the months from December-MayIn August Very few moths were

and no moths were attracted to light in June Catches of moths were

highest in 1977

6

The four week moving means of the trap catches are presented in

Figl The insect population as indicated by trap catches was lower

during 1974-76 and 1979-80 (Figl) The insect activity was higher during

August-September The trap catches were higher during 1977 when extensive

damage occured in sorghum and pearl-millet The trap catches differed

between locations (Fig2) The maximum number of moths were caught In the

trap located in the vertisol watersheds which is in the midst of a large

area planted to sorghum and maize The trap catches were considerably

lower in traps located at Manmool village (tnap surrounded by off-season

nursery area irrigated paddy fields and rainfed alfisols) Crop

Improvement Building and RA-l(near the Hyderabad-Bombay highway with trees

on one side and rainfed alfisols on the other)

The light trap catches temperature humidity and rainfall frnom 1976

to 1980 are presented in Fig3 The peak activity period moved ahead by

5-6 weeks from 1976 to 1980 The insect population appeared to follow the

changes in weather However no single factor exercised marked effect on

the insect populations Generally more moths were caught during periods

of low rainfall preceded by a 2-4 week period of normal rainfall During

1980 there was no distinct period of prolonged drought and the trap

catches declined with the decrease in the amount of rainfall The trap

catches during 1979 showed considerable insect activity up to November

when a bimodAl pattern of rainfall was experienced The insect population

was highest during 1977 when rainfall was low and erratic The maximum

activity period was also preceded by 4-5 weeks of moderate temperatures

(20-30C) higher humidity (50-95) and smaller differences between the

maximum and minimum temperatures and RH These conditions are highly

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

STUDIES ON MYTHIMNA SEPARATA AT ICRIFAT

HC Sharma VS Bhatnagar and JC Davies

1 INTRODUCTION

The oriental armyworm Mythimna (Pseudaletia)(Leucania) separata

Walker is a pest of cereals in Asia and Australia between 450N

to 450 S latitude and 60 E to beyond 170 W longitude It has been

reported to feed in nature on 33 plant species and some unshy

specified grasses belonging to eight plant families (Sharma amp

Davies 1982) Prior to 1950 it was of minor importance in India

In the last two decades extensive damage has been reported from

over 25 places in different parts of India It has become a serious

pest on sorghum millets rice maize and wheat with the increase In

irrigated areas and the consequent changes in farming systems

introduction of high yielding varieties heavy fertilizer use and

continuous cultivation (Bindra and Singh 1973 Verma and Khurana

1971 and Gopinadhan and Kushwaha 1978)

At ICRISAT Center outbreak of Mythimna separata defoliating

sorghum and pearl-millet was recorded In 1977 Consequently the biology

and population dynamics of the pest has been studied and efforts made

2

2

to screen pearl millet and sorghum genotypes for resistance to this

pest The report covers the results of the studies carried out on

these and related aspects over the past several years at the ICRISAT

Center

INCIDENCE AND BIOLOGY

In the period 1977-79 Mythimna damage or larval population was recorded

by selecting 100 plants (at random) diagonally across sorghum and pearl

millet fields Usually a number of fields on two soil types (Alfisols

and Vertisols) were included in samples to determine the range of

infestation In 197 8 sampling was continuous throuyhout the year

Additional data from sole and intercropped sorghum (with pigeonpea)

were recorded in large intercropping trials between 1975 to 1980 In

these observations the number of larvae were recorded from 100 plants or

earheads

At ICRISAT Center Mythimna separata larvae severely damage pearl-millet

and sorghum during August-September (Tablel In alfisols pearl millet

sustained higher damage compared to sorghum Extensive defoliation was

observed during 1977 when its first outbreak occured

In intercropping trials upto 106 larvae100 plants were recorded

during 1977 (Table 2) The larval populations were considerable in

subsequent seasons though far less than that of 1977 Larvae were observed

in June 7-10 days after the first few showers of monsoon rains

3

The biology of the insect was studied during October 1979 and

January-February 1980 under ambient temperature and relative humidity

3 The moths obtained from the field collected larvae were kept in 30 cm

cages The moths were provided with 10 honey solution in a cotton

swab The eggs were laid on dry sorghum leaves or butter paper placed

at the bottom of the cage Larvae were fed on sorghum leaves in 1 ltr

plastic jars Data were recorded on the development of the various stadia

and on other biological aspects such as oviposition and sex ratio

The females laid an average of 996 eggs after a pre-oviposition

period of 2-5 days Oviposition continued for 2-7 days after emergence

(Table 3) Egg incubation took 4-5 days The larval instars I-VII

averaged 39 33 31 27 31 22 amp 18 days respectively Preshy

pupal and pupal periods lasted for 1-2 and 8-12 days respectively The

entire post-embryonic development was completed in 29-39 days A third

instar larva weighed on an average OlO-O15g and a pupa 026-042g

3 OUTBREAKS

Outbreaks of M separata occured at ICRISAT Center during 1977 1978

1980 Outbreaks at other locations have been recorded during 1980-81

at Dharwad and at Anantapur and Nandyal during 1981

Mythimna outbreaks have occured in India and elsewhere in many

seasons (Sharma amp Davies 1982) A basic knowledge of (a) temperature

and RH requirements of the insect in the ecosystem (b) availability

14

of suitable hosts (c)migration and (d)extent of parasitism and

parasites involved may help to understand the factors controlling

the insect population The outbreaks in India China Japan Bangladesh

New Zealand Fiji and Australia have been attributed to (a) the owqrrenc

of drought following rains (b) floods resulting from heavy rainfall

(c) Induction of migrant populations into a geographic area(d) heavy

fertilizer use (e) trash mulching and (f) temperature and humidity

regimes in the periods preceding and during the outbreaks (Butani 1955

Puttarudriah and Usrnan 1957 Chin 1979 Grist and Lever 1969 Avasthy

and Chaudhary 1965 and Koyama 1966) High rainfall possibly leads to

high humidity and more food which are very essential for survival and

development of the larvae Prolonged periods of drought following rains may

possibly restrict the activity of natural control agents (parasites

predators amp diseases) Heavy manuring leads to better crop growth for

insect feeding and development Trash mulching provides a good site

for oviposition and better place for the larvae to hide in

The factors resulting in outbreaks at ICRISAT Center and other

places are not fully understood The light traps have not Indicated

the arrival of migrant populations Moreover the phototropic behaviour

of migrant moths is not fully known Duelng 1977-78 the outbreaks

possibly resulted from drought preceded by a period of normal rainfall

while during 1980 the outbreak was preceded by a period of heavy rainfall

The build up of damaging populatlons at ICRISAT Center might have resulted

from lavish crop growth and heavy use of fertilizers Another factor

may be the low parasitism and disease levels (around 30) observed at

ICRISAT Center as against gt75 in Punjab and Rajasthan (Butter 1978

5

and Gopinadhan and Kushwaha 1978) due to Apanteles ruficrus and Bacillus

cereus respectively Anantapur experienced the first recorded outbreak

during 1981 It is a drought-prone area and unusually in that year normal

and well distributed rainfall was experienced The arrival of migrant

populations or build of native populations in the absence of parasites

might have led to population explosion A close examination of the case

histories of a number of outbreaks may help to elucidate the factor(s)

leadiny to opulation explosion

4 POPULATION DYNAMICS

41 ADULTS

Activity of adult Mythimna spV was monitored daily using light traps

(Bhatnagar and Davies 1979) installed at three locations at ICRISAT

Center The data were converted into 4 week moving means to allow for

moon phase effects (Bhatnagar and Davies 1978)

The site of one light trap (Site 1) on an alfisol which wa operated

continuously between Aug 1974 and July1979 was subsequently changed The

light traps at 3ite 2 (alfisol) and Site 3 (vertisol) were commissioned

In Sept 1975 and May 1977 respectively Light trap catches at ICRISAT

Cencer over the four ear period (1977-80) at three locations are given In

Table4 Most moths were caught durlng September but catches were high

recorded in the months from December-MayIn August Very few moths were

and no moths were attracted to light in June Catches of moths were

highest in 1977

6

The four week moving means of the trap catches are presented in

Figl The insect population as indicated by trap catches was lower

during 1974-76 and 1979-80 (Figl) The insect activity was higher during

August-September The trap catches were higher during 1977 when extensive

damage occured in sorghum and pearl-millet The trap catches differed

between locations (Fig2) The maximum number of moths were caught In the

trap located in the vertisol watersheds which is in the midst of a large

area planted to sorghum and maize The trap catches were considerably

lower in traps located at Manmool village (tnap surrounded by off-season

nursery area irrigated paddy fields and rainfed alfisols) Crop

Improvement Building and RA-l(near the Hyderabad-Bombay highway with trees

on one side and rainfed alfisols on the other)

The light trap catches temperature humidity and rainfall frnom 1976

to 1980 are presented in Fig3 The peak activity period moved ahead by

5-6 weeks from 1976 to 1980 The insect population appeared to follow the

changes in weather However no single factor exercised marked effect on

the insect populations Generally more moths were caught during periods

of low rainfall preceded by a 2-4 week period of normal rainfall During

1980 there was no distinct period of prolonged drought and the trap

catches declined with the decrease in the amount of rainfall The trap

catches during 1979 showed considerable insect activity up to November

when a bimodAl pattern of rainfall was experienced The insect population

was highest during 1977 when rainfall was low and erratic The maximum

activity period was also preceded by 4-5 weeks of moderate temperatures

(20-30C) higher humidity (50-95) and smaller differences between the

maximum and minimum temperatures and RH These conditions are highly

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

2

2

to screen pearl millet and sorghum genotypes for resistance to this

pest The report covers the results of the studies carried out on

these and related aspects over the past several years at the ICRISAT

Center

INCIDENCE AND BIOLOGY

In the period 1977-79 Mythimna damage or larval population was recorded

by selecting 100 plants (at random) diagonally across sorghum and pearl

millet fields Usually a number of fields on two soil types (Alfisols

and Vertisols) were included in samples to determine the range of

infestation In 197 8 sampling was continuous throuyhout the year

Additional data from sole and intercropped sorghum (with pigeonpea)

were recorded in large intercropping trials between 1975 to 1980 In

these observations the number of larvae were recorded from 100 plants or

earheads

At ICRISAT Center Mythimna separata larvae severely damage pearl-millet

and sorghum during August-September (Tablel In alfisols pearl millet

sustained higher damage compared to sorghum Extensive defoliation was

observed during 1977 when its first outbreak occured

In intercropping trials upto 106 larvae100 plants were recorded

during 1977 (Table 2) The larval populations were considerable in

subsequent seasons though far less than that of 1977 Larvae were observed

in June 7-10 days after the first few showers of monsoon rains

3

The biology of the insect was studied during October 1979 and

January-February 1980 under ambient temperature and relative humidity

3 The moths obtained from the field collected larvae were kept in 30 cm

cages The moths were provided with 10 honey solution in a cotton

swab The eggs were laid on dry sorghum leaves or butter paper placed

at the bottom of the cage Larvae were fed on sorghum leaves in 1 ltr

plastic jars Data were recorded on the development of the various stadia

and on other biological aspects such as oviposition and sex ratio

The females laid an average of 996 eggs after a pre-oviposition

period of 2-5 days Oviposition continued for 2-7 days after emergence

(Table 3) Egg incubation took 4-5 days The larval instars I-VII

averaged 39 33 31 27 31 22 amp 18 days respectively Preshy

pupal and pupal periods lasted for 1-2 and 8-12 days respectively The

entire post-embryonic development was completed in 29-39 days A third

instar larva weighed on an average OlO-O15g and a pupa 026-042g

3 OUTBREAKS

Outbreaks of M separata occured at ICRISAT Center during 1977 1978

1980 Outbreaks at other locations have been recorded during 1980-81

at Dharwad and at Anantapur and Nandyal during 1981

Mythimna outbreaks have occured in India and elsewhere in many

seasons (Sharma amp Davies 1982) A basic knowledge of (a) temperature

and RH requirements of the insect in the ecosystem (b) availability

14

of suitable hosts (c)migration and (d)extent of parasitism and

parasites involved may help to understand the factors controlling

the insect population The outbreaks in India China Japan Bangladesh

New Zealand Fiji and Australia have been attributed to (a) the owqrrenc

of drought following rains (b) floods resulting from heavy rainfall

(c) Induction of migrant populations into a geographic area(d) heavy

fertilizer use (e) trash mulching and (f) temperature and humidity

regimes in the periods preceding and during the outbreaks (Butani 1955

Puttarudriah and Usrnan 1957 Chin 1979 Grist and Lever 1969 Avasthy

and Chaudhary 1965 and Koyama 1966) High rainfall possibly leads to

high humidity and more food which are very essential for survival and

development of the larvae Prolonged periods of drought following rains may

possibly restrict the activity of natural control agents (parasites

predators amp diseases) Heavy manuring leads to better crop growth for

insect feeding and development Trash mulching provides a good site

for oviposition and better place for the larvae to hide in

The factors resulting in outbreaks at ICRISAT Center and other

places are not fully understood The light traps have not Indicated

the arrival of migrant populations Moreover the phototropic behaviour

of migrant moths is not fully known Duelng 1977-78 the outbreaks

possibly resulted from drought preceded by a period of normal rainfall

while during 1980 the outbreak was preceded by a period of heavy rainfall

The build up of damaging populatlons at ICRISAT Center might have resulted

from lavish crop growth and heavy use of fertilizers Another factor

may be the low parasitism and disease levels (around 30) observed at

ICRISAT Center as against gt75 in Punjab and Rajasthan (Butter 1978

5

and Gopinadhan and Kushwaha 1978) due to Apanteles ruficrus and Bacillus

cereus respectively Anantapur experienced the first recorded outbreak

during 1981 It is a drought-prone area and unusually in that year normal

and well distributed rainfall was experienced The arrival of migrant

populations or build of native populations in the absence of parasites

might have led to population explosion A close examination of the case

histories of a number of outbreaks may help to elucidate the factor(s)

leadiny to opulation explosion

4 POPULATION DYNAMICS

41 ADULTS

Activity of adult Mythimna spV was monitored daily using light traps

(Bhatnagar and Davies 1979) installed at three locations at ICRISAT

Center The data were converted into 4 week moving means to allow for

moon phase effects (Bhatnagar and Davies 1978)

The site of one light trap (Site 1) on an alfisol which wa operated

continuously between Aug 1974 and July1979 was subsequently changed The

light traps at 3ite 2 (alfisol) and Site 3 (vertisol) were commissioned

In Sept 1975 and May 1977 respectively Light trap catches at ICRISAT

Cencer over the four ear period (1977-80) at three locations are given In

Table4 Most moths were caught durlng September but catches were high

recorded in the months from December-MayIn August Very few moths were

and no moths were attracted to light in June Catches of moths were

highest in 1977

6

The four week moving means of the trap catches are presented in

Figl The insect population as indicated by trap catches was lower

during 1974-76 and 1979-80 (Figl) The insect activity was higher during

August-September The trap catches were higher during 1977 when extensive

damage occured in sorghum and pearl-millet The trap catches differed

between locations (Fig2) The maximum number of moths were caught In the

trap located in the vertisol watersheds which is in the midst of a large

area planted to sorghum and maize The trap catches were considerably

lower in traps located at Manmool village (tnap surrounded by off-season

nursery area irrigated paddy fields and rainfed alfisols) Crop

Improvement Building and RA-l(near the Hyderabad-Bombay highway with trees

on one side and rainfed alfisols on the other)

The light trap catches temperature humidity and rainfall frnom 1976

to 1980 are presented in Fig3 The peak activity period moved ahead by

5-6 weeks from 1976 to 1980 The insect population appeared to follow the

changes in weather However no single factor exercised marked effect on

the insect populations Generally more moths were caught during periods

of low rainfall preceded by a 2-4 week period of normal rainfall During

1980 there was no distinct period of prolonged drought and the trap

catches declined with the decrease in the amount of rainfall The trap

catches during 1979 showed considerable insect activity up to November

when a bimodAl pattern of rainfall was experienced The insect population

was highest during 1977 when rainfall was low and erratic The maximum

activity period was also preceded by 4-5 weeks of moderate temperatures

(20-30C) higher humidity (50-95) and smaller differences between the

maximum and minimum temperatures and RH These conditions are highly

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

3

The biology of the insect was studied during October 1979 and

January-February 1980 under ambient temperature and relative humidity

3 The moths obtained from the field collected larvae were kept in 30 cm

cages The moths were provided with 10 honey solution in a cotton

swab The eggs were laid on dry sorghum leaves or butter paper placed

at the bottom of the cage Larvae were fed on sorghum leaves in 1 ltr

plastic jars Data were recorded on the development of the various stadia

and on other biological aspects such as oviposition and sex ratio

The females laid an average of 996 eggs after a pre-oviposition

period of 2-5 days Oviposition continued for 2-7 days after emergence

(Table 3) Egg incubation took 4-5 days The larval instars I-VII

averaged 39 33 31 27 31 22 amp 18 days respectively Preshy

pupal and pupal periods lasted for 1-2 and 8-12 days respectively The

entire post-embryonic development was completed in 29-39 days A third

instar larva weighed on an average OlO-O15g and a pupa 026-042g

3 OUTBREAKS

Outbreaks of M separata occured at ICRISAT Center during 1977 1978

1980 Outbreaks at other locations have been recorded during 1980-81

at Dharwad and at Anantapur and Nandyal during 1981

Mythimna outbreaks have occured in India and elsewhere in many

seasons (Sharma amp Davies 1982) A basic knowledge of (a) temperature

and RH requirements of the insect in the ecosystem (b) availability

14

of suitable hosts (c)migration and (d)extent of parasitism and

parasites involved may help to understand the factors controlling

the insect population The outbreaks in India China Japan Bangladesh

New Zealand Fiji and Australia have been attributed to (a) the owqrrenc

of drought following rains (b) floods resulting from heavy rainfall

(c) Induction of migrant populations into a geographic area(d) heavy

fertilizer use (e) trash mulching and (f) temperature and humidity

regimes in the periods preceding and during the outbreaks (Butani 1955

Puttarudriah and Usrnan 1957 Chin 1979 Grist and Lever 1969 Avasthy

and Chaudhary 1965 and Koyama 1966) High rainfall possibly leads to

high humidity and more food which are very essential for survival and

development of the larvae Prolonged periods of drought following rains may

possibly restrict the activity of natural control agents (parasites

predators amp diseases) Heavy manuring leads to better crop growth for

insect feeding and development Trash mulching provides a good site

for oviposition and better place for the larvae to hide in

The factors resulting in outbreaks at ICRISAT Center and other

places are not fully understood The light traps have not Indicated

the arrival of migrant populations Moreover the phototropic behaviour

of migrant moths is not fully known Duelng 1977-78 the outbreaks

possibly resulted from drought preceded by a period of normal rainfall

while during 1980 the outbreak was preceded by a period of heavy rainfall

The build up of damaging populatlons at ICRISAT Center might have resulted

from lavish crop growth and heavy use of fertilizers Another factor

may be the low parasitism and disease levels (around 30) observed at

ICRISAT Center as against gt75 in Punjab and Rajasthan (Butter 1978

5

and Gopinadhan and Kushwaha 1978) due to Apanteles ruficrus and Bacillus

cereus respectively Anantapur experienced the first recorded outbreak

during 1981 It is a drought-prone area and unusually in that year normal

and well distributed rainfall was experienced The arrival of migrant

populations or build of native populations in the absence of parasites

might have led to population explosion A close examination of the case

histories of a number of outbreaks may help to elucidate the factor(s)

leadiny to opulation explosion

4 POPULATION DYNAMICS

41 ADULTS

Activity of adult Mythimna spV was monitored daily using light traps

(Bhatnagar and Davies 1979) installed at three locations at ICRISAT

Center The data were converted into 4 week moving means to allow for

moon phase effects (Bhatnagar and Davies 1978)

The site of one light trap (Site 1) on an alfisol which wa operated

continuously between Aug 1974 and July1979 was subsequently changed The

light traps at 3ite 2 (alfisol) and Site 3 (vertisol) were commissioned

In Sept 1975 and May 1977 respectively Light trap catches at ICRISAT

Cencer over the four ear period (1977-80) at three locations are given In

Table4 Most moths were caught durlng September but catches were high

recorded in the months from December-MayIn August Very few moths were

and no moths were attracted to light in June Catches of moths were

highest in 1977

6

The four week moving means of the trap catches are presented in

Figl The insect population as indicated by trap catches was lower

during 1974-76 and 1979-80 (Figl) The insect activity was higher during

August-September The trap catches were higher during 1977 when extensive

damage occured in sorghum and pearl-millet The trap catches differed

between locations (Fig2) The maximum number of moths were caught In the

trap located in the vertisol watersheds which is in the midst of a large

area planted to sorghum and maize The trap catches were considerably

lower in traps located at Manmool village (tnap surrounded by off-season

nursery area irrigated paddy fields and rainfed alfisols) Crop

Improvement Building and RA-l(near the Hyderabad-Bombay highway with trees

on one side and rainfed alfisols on the other)

The light trap catches temperature humidity and rainfall frnom 1976

to 1980 are presented in Fig3 The peak activity period moved ahead by

5-6 weeks from 1976 to 1980 The insect population appeared to follow the

changes in weather However no single factor exercised marked effect on

the insect populations Generally more moths were caught during periods

of low rainfall preceded by a 2-4 week period of normal rainfall During

1980 there was no distinct period of prolonged drought and the trap

catches declined with the decrease in the amount of rainfall The trap

catches during 1979 showed considerable insect activity up to November

when a bimodAl pattern of rainfall was experienced The insect population

was highest during 1977 when rainfall was low and erratic The maximum

activity period was also preceded by 4-5 weeks of moderate temperatures

(20-30C) higher humidity (50-95) and smaller differences between the

maximum and minimum temperatures and RH These conditions are highly

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

14

of suitable hosts (c)migration and (d)extent of parasitism and

parasites involved may help to understand the factors controlling

the insect population The outbreaks in India China Japan Bangladesh

New Zealand Fiji and Australia have been attributed to (a) the owqrrenc

of drought following rains (b) floods resulting from heavy rainfall

(c) Induction of migrant populations into a geographic area(d) heavy

fertilizer use (e) trash mulching and (f) temperature and humidity

regimes in the periods preceding and during the outbreaks (Butani 1955

Puttarudriah and Usrnan 1957 Chin 1979 Grist and Lever 1969 Avasthy

and Chaudhary 1965 and Koyama 1966) High rainfall possibly leads to

high humidity and more food which are very essential for survival and

development of the larvae Prolonged periods of drought following rains may

possibly restrict the activity of natural control agents (parasites

predators amp diseases) Heavy manuring leads to better crop growth for

insect feeding and development Trash mulching provides a good site

for oviposition and better place for the larvae to hide in

The factors resulting in outbreaks at ICRISAT Center and other

places are not fully understood The light traps have not Indicated

the arrival of migrant populations Moreover the phototropic behaviour

of migrant moths is not fully known Duelng 1977-78 the outbreaks

possibly resulted from drought preceded by a period of normal rainfall

while during 1980 the outbreak was preceded by a period of heavy rainfall

The build up of damaging populatlons at ICRISAT Center might have resulted

from lavish crop growth and heavy use of fertilizers Another factor

may be the low parasitism and disease levels (around 30) observed at

ICRISAT Center as against gt75 in Punjab and Rajasthan (Butter 1978

5

and Gopinadhan and Kushwaha 1978) due to Apanteles ruficrus and Bacillus

cereus respectively Anantapur experienced the first recorded outbreak

during 1981 It is a drought-prone area and unusually in that year normal

and well distributed rainfall was experienced The arrival of migrant

populations or build of native populations in the absence of parasites

might have led to population explosion A close examination of the case

histories of a number of outbreaks may help to elucidate the factor(s)

leadiny to opulation explosion

4 POPULATION DYNAMICS

41 ADULTS

Activity of adult Mythimna spV was monitored daily using light traps

(Bhatnagar and Davies 1979) installed at three locations at ICRISAT

Center The data were converted into 4 week moving means to allow for

moon phase effects (Bhatnagar and Davies 1978)

The site of one light trap (Site 1) on an alfisol which wa operated

continuously between Aug 1974 and July1979 was subsequently changed The

light traps at 3ite 2 (alfisol) and Site 3 (vertisol) were commissioned

In Sept 1975 and May 1977 respectively Light trap catches at ICRISAT

Cencer over the four ear period (1977-80) at three locations are given In

Table4 Most moths were caught durlng September but catches were high

recorded in the months from December-MayIn August Very few moths were

and no moths were attracted to light in June Catches of moths were

highest in 1977

6

The four week moving means of the trap catches are presented in

Figl The insect population as indicated by trap catches was lower

during 1974-76 and 1979-80 (Figl) The insect activity was higher during

August-September The trap catches were higher during 1977 when extensive

damage occured in sorghum and pearl-millet The trap catches differed

between locations (Fig2) The maximum number of moths were caught In the

trap located in the vertisol watersheds which is in the midst of a large

area planted to sorghum and maize The trap catches were considerably

lower in traps located at Manmool village (tnap surrounded by off-season

nursery area irrigated paddy fields and rainfed alfisols) Crop

Improvement Building and RA-l(near the Hyderabad-Bombay highway with trees

on one side and rainfed alfisols on the other)

The light trap catches temperature humidity and rainfall frnom 1976

to 1980 are presented in Fig3 The peak activity period moved ahead by

5-6 weeks from 1976 to 1980 The insect population appeared to follow the

changes in weather However no single factor exercised marked effect on

the insect populations Generally more moths were caught during periods

of low rainfall preceded by a 2-4 week period of normal rainfall During

1980 there was no distinct period of prolonged drought and the trap

catches declined with the decrease in the amount of rainfall The trap

catches during 1979 showed considerable insect activity up to November

when a bimodAl pattern of rainfall was experienced The insect population

was highest during 1977 when rainfall was low and erratic The maximum

activity period was also preceded by 4-5 weeks of moderate temperatures

(20-30C) higher humidity (50-95) and smaller differences between the

maximum and minimum temperatures and RH These conditions are highly

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

5

and Gopinadhan and Kushwaha 1978) due to Apanteles ruficrus and Bacillus

cereus respectively Anantapur experienced the first recorded outbreak

during 1981 It is a drought-prone area and unusually in that year normal

and well distributed rainfall was experienced The arrival of migrant

populations or build of native populations in the absence of parasites

might have led to population explosion A close examination of the case

histories of a number of outbreaks may help to elucidate the factor(s)

leadiny to opulation explosion

4 POPULATION DYNAMICS

41 ADULTS

Activity of adult Mythimna spV was monitored daily using light traps

(Bhatnagar and Davies 1979) installed at three locations at ICRISAT

Center The data were converted into 4 week moving means to allow for

moon phase effects (Bhatnagar and Davies 1978)

The site of one light trap (Site 1) on an alfisol which wa operated

continuously between Aug 1974 and July1979 was subsequently changed The

light traps at 3ite 2 (alfisol) and Site 3 (vertisol) were commissioned

In Sept 1975 and May 1977 respectively Light trap catches at ICRISAT

Cencer over the four ear period (1977-80) at three locations are given In

Table4 Most moths were caught durlng September but catches were high

recorded in the months from December-MayIn August Very few moths were

and no moths were attracted to light in June Catches of moths were

highest in 1977

6

The four week moving means of the trap catches are presented in

Figl The insect population as indicated by trap catches was lower

during 1974-76 and 1979-80 (Figl) The insect activity was higher during

August-September The trap catches were higher during 1977 when extensive

damage occured in sorghum and pearl-millet The trap catches differed

between locations (Fig2) The maximum number of moths were caught In the

trap located in the vertisol watersheds which is in the midst of a large

area planted to sorghum and maize The trap catches were considerably

lower in traps located at Manmool village (tnap surrounded by off-season

nursery area irrigated paddy fields and rainfed alfisols) Crop

Improvement Building and RA-l(near the Hyderabad-Bombay highway with trees

on one side and rainfed alfisols on the other)

The light trap catches temperature humidity and rainfall frnom 1976

to 1980 are presented in Fig3 The peak activity period moved ahead by

5-6 weeks from 1976 to 1980 The insect population appeared to follow the

changes in weather However no single factor exercised marked effect on

the insect populations Generally more moths were caught during periods

of low rainfall preceded by a 2-4 week period of normal rainfall During

1980 there was no distinct period of prolonged drought and the trap

catches declined with the decrease in the amount of rainfall The trap

catches during 1979 showed considerable insect activity up to November

when a bimodAl pattern of rainfall was experienced The insect population

was highest during 1977 when rainfall was low and erratic The maximum

activity period was also preceded by 4-5 weeks of moderate temperatures

(20-30C) higher humidity (50-95) and smaller differences between the

maximum and minimum temperatures and RH These conditions are highly

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

6

The four week moving means of the trap catches are presented in

Figl The insect population as indicated by trap catches was lower

during 1974-76 and 1979-80 (Figl) The insect activity was higher during

August-September The trap catches were higher during 1977 when extensive

damage occured in sorghum and pearl-millet The trap catches differed

between locations (Fig2) The maximum number of moths were caught In the

trap located in the vertisol watersheds which is in the midst of a large

area planted to sorghum and maize The trap catches were considerably

lower in traps located at Manmool village (tnap surrounded by off-season

nursery area irrigated paddy fields and rainfed alfisols) Crop

Improvement Building and RA-l(near the Hyderabad-Bombay highway with trees

on one side and rainfed alfisols on the other)

The light trap catches temperature humidity and rainfall frnom 1976

to 1980 are presented in Fig3 The peak activity period moved ahead by

5-6 weeks from 1976 to 1980 The insect population appeared to follow the

changes in weather However no single factor exercised marked effect on

the insect populations Generally more moths were caught during periods

of low rainfall preceded by a 2-4 week period of normal rainfall During

1980 there was no distinct period of prolonged drought and the trap

catches declined with the decrease in the amount of rainfall The trap

catches during 1979 showed considerable insect activity up to November

when a bimodAl pattern of rainfall was experienced The insect population

was highest during 1977 when rainfall was low and erratic The maximum

activity period was also preceded by 4-5 weeks of moderate temperatures

(20-30C) higher humidity (50-95) and smaller differences between the

maximum and minimum temperatures and RH These conditions are highly

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

7

congenial for ovipositi-on egg hatching and larval survival and development

During the post-rainy and summer seasons very few or no moths were caught

when temperatures dropped to lt 200 C or went up to gt 350 C and RH fell below

50

Populations of Mythimna lorey Duponchel showed different patterns

of pupulation fluctuation (un-published data) The populations of

M lorei as indicated by light traps were higher than those of M

separata though its larval population and damage on sorghum and pearlshy

millet remain very low at the ICRISAT Center Interestingly the

population of M loreyi during 1977 was the lowest while that of

M separata was tne maximum though both are closely relted

42 LARVAE

The larval population was monitored at four locations at ICRISAT Center

(pesticide free alfisols and vertisols and pesticide treated alfisols

and vertisols) and at a farmers field (4 km west of ICRISAT Center)

2 at fortnightly intervals Three plots of 48 m were marked in each

location diagonally The larval survey began during July when the crop

(sorghum or pearl millet) was 10-15-days old The plant population was

recorded in each plot Larvae were counted carefully in these plots

The survey continued till crop maturity In the post 3rainy season

the surveys were conducted in fields having sorghum or millet irrespective

of location During 1980 kharif the pesticide treated alfisols received

one application of endosulfan (07 kg alha) on pearl millet against

Mythimna separata and Heliothis armigera on 2881980 In pesticide

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

890a412 7 190ad ntMloeu p adAhrgn oc

07 g i lied on pearl milletIn formen wereap the alfisols The a

against A thericona Soccata on I 719811 and 97181 an edo fan

( 07 kg alha) against ythimna separata and Hel iathis armi era on 1871 981

i~i I I 1791981 on sorghumiand respectively At t e ime ofgr i iling stage carbaryl (tI kg a[ha0 applied againstgwas uStatus mon sorghu

Larval populations monitored during 1980-81 are given In Flg ab

Maximum numbers of larvae were observed cdoring August while thepekI

- the trap catches of moths wbs recorded during September Lavvai population

as well as trap catches declined durilng October The population waslower

in pesticide free afisols than in the treated fields In vetthsols there

was little dfferee on treated and pesticide free fields in9

insect poplations were detectd by light traps 3 5 weeks after peak larval

i- po pu la t io n i

inpete fre atsl Mthamnain the troaled tieldsain evertisols there4

From thed account that the l ght traps are notforegoing is apparent

rausefin Indicating the begnningof infestations and that themode

of carryover and s of Initia infesta tions Isnot fully understod9-T anr es n soterinttation of rains iends tagthe monsoon Maimne of larvae aere os folw At hil eeak in(

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

The moths possibly resort to migration from one place to another depending

upon the weather conditions The migrant behaviour of this insect has

been well established in China and Japan (Ma 1979 Quo et al 1963 Lin

and Chang 1964 Li et al 1963 amp 1965 Koyama 1970 Chen et al 1965

Oku and Koyani 1976 and Nagano et al 1972) The period before sexual maturity

has been suggested as the optimum time for long distance migration (Hwang

and How 1966) In China moths from South China are considered to be a

source of early spring populations which follow ascending trans and

descending movements (Lin (Chang-Shan) 1963) The moths can fly 600-1400 km

(Grist and Lever 1969) and have been intercepted even over the sea (Hsla et a]

1963 and Asahlna 1968) The moths also follow the air currents (Oku and

Kobayashi 1974 and Lin et al 1963)

Light traps are possibly Ineffective under low population levels

Alternatively during unfaourable conditions the moths may resort to

migration and possibly do not respond to light traps This point derives

support from the fact that during December 1981 none of the 500 un-mated

moths released about 100 m away from the light trap responded to it The

low population levels during the post rainy season in spite of substantial

area planted to pearl-millet and sorghum indicate the possible movement of

moths away from this place Alternatively decreased egg hatching and

larval survival because of lower humidity and lower or higher temperatures

(than the optimum) may be another possible causes of low population levels

PARASITIZATOON

During the fortnightly surveys samples each of 50-60 larvae were collected

from different locations The larvae were reared in the laboratory and

5

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

10

data were recorded on pupation adult emergenee the number of larvae

parasitized the parasites involved and the natural mortality due to

other factors such as fungi viruses and bacteria The data on parasitism

were also supplemented by additional field collections

From over 5000 field collected larvae we recovered six hymenopterous

parasites (Apanteles spp Disophrys sp Metopius rufus Campoletis chloridae

and Enicospilus sp) and four dipteran parasites (Exorista xanthaspis Carcelia

spp Palexorista solemnis and Megaselia sp) Mermithid nematodes were also

recorded as one of the important parasitic groups Anedrallus spinidens was

observed preying on the larvae at Hissar

Larval populationunit area their survival and parasitization are

given in fig5 ab and Table5 Larval populations were much lower in the

Farmers fields and the pesticide free alfisols at ICRISAT Center than In

treated alfisols and vertisols and pesticide free vertisols In the

treated alfisols and vertisols and pesticide free vertisols the larval

pupation and adult emergence were lower than in pesticide free alfisols

The larval population and parasitism levels were higher during 1980 than

those in 1981 Hymenopterans were the major parasites and their activity

tended to be higher in vertisols than in alfisols The dipteran parasites

also showed higher activity in vertisols though their incidence was much

lower overall than that of hymenopteran parasites

Puation and adult emergence were higher in larvae collected from

pearl-millet as compared to those collected from sorghum (Fig6) However

the larval parasitization was much hiqher in sorghum than in pearl-millet

Hymenopterous parasites were much more abundant in sorghum than in pearlshy

millet The dipteran parasites though less common than hymenopteran parasites

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

II

were also more common in sorghum than in pearl-millet (Table 5) The

sex ratio showed that there was a greater proportion of female moths in

milet than those from sorghumpopulations collected from pearl

The pupation and adult emergence of the field collected larvae

decreased considerably from June to October (Table 6) The sex ratio

(malesfemales) also tended to decrease from June to October It was

higher during 1980 compared to 1981 The significance of this change

and the factors effecting this phenomenon need to be looked into critically

Parasitization increased considerably from June to September and slightly

declined during October The larval mortality due to other factors did not

show any trend across the season and generally ranged between 125 during

September 1980 to 483 during December 1979

Larval survival and parasitism levels did not differ substantially in

four pearl-millet cultivars having four weeding treatments (Table 7) The

parasitism by hymenopterans was very low ( lt 17 parasitism) Mermithids

were the most important parasites (10-18 parasitism) These parasitism

levels by mermithids were much higher than those recorded at other locations

Forty two pzlrasites IS predators 4 bacteria 5 fungi and 3 viral strains

agents of Mythimna separata (Sharma andhave been reported as natural control

Davies 1982) At ICRISAT Center the Aoanteles ruficrus and

Exortista xanthaspis were the most important The negligible larval parasitism

in pearl millet may partially explain the heavy leaf defoliationby hymenoptera

experienced in pearl-millet than in sorghum On sorghum the parasites killed

about 25-30 of the larvae The parasite activity did not differ substantially

in protected and unprotected areas This phenomenon need to be looked into

more intensively At ICRISAT Center the heavy infection and mortality due

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

12

to diseases (bacteria and virus) have not been observed as reported elsewhere

(Bindra and Singh1973 Gopinadhan amp Kushwaha 1978 and Neelgund and Mathad

1972) It is likely that ar more effective strains of parasites and

pathogens are present in other areas Complete biological control of this

armyworm has been achieved in New Zealand by using a strain of Apanteles

ruficrus imported from Pakistan (Simmonds 1976 Simmonds and Bonnett 1977

and Mohyuddin and Shah 1977) In the light of above observations the

transfer of effective natural cnntrol agents within the country should be

actively considered

6 HOST PLANT RESISTANCE

61 HOST RANGE

No directed efforts were made to study the host range of Mythimna However

periodical observations were made on the-plant species upon which the larvae

were found feeding Mythimna separata has been observed feeding on pearl

millet (Pennisetum aniericanum)sorghum (Sorqhum bicolor) Maize (Zea mays)

rice (Oryza sativa) and bermuda grass (Cynodon dactylon) at ICRISAT Center

and on Italian millet (Setaria italica) and Kodo millet (Paspalm scrobicultatum)

at Anantapur (in addition to pearl millet and sorghum) It has been reported

feeding upon 33 plant species and some unspecified grasses belonging to eight

families (Sharma amp Davies 1982) However it is a major pest of Gramineae

The food preference utilization and larval development varies on different

host plants (Kalode et al 1971) During 1981 in an outbreak situation at

Anantapur the larvae completely defoliated pearl and Italian nlillet while

there was very little damage in Kodo millet

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

62 RESISTANCE SCREENING

A set of 40 pearl-millet genotypes (belonging to different geographical

regions) was tested using plastic pots and metal trays under free choice

test However the damage ratings varied conflderably in different

replications To avoid these problems a set of 12 genotypes was tested

under no choice situation using glass ch~mneys

The entries were grown in plastic pots (15x15xO cm) Each pot

had five seedlings Fifteen days after germination 3 pairs of pots with

uniform plant growth were selected from the 10 pots raised for each genotype

The plants in each pot were covered with a glass chimney and one pot from

each pair was infested with 3rd instar larvae one larvaplant

After 24 hr the larvae were removed The data were recorded on leaf

area dry weight and leaf damage The leaf area (measured by leaf area meter)

and dry weight consumed by the larvae were expressed as percentages of the

control pots

During kharif 1980 a field trial containing 36 hybrids (repllcatlons-3

plot size 8 rows 4M long design RBD) was rated for Mythlmna damage on

1-5 scale (I -410 leaf area damaged and 5 =gt75 leaf area damaged)under

natural incidence of the pest

There were significant differences in genotypic susceptibility to

leaf damage by Mythimna separata larvae (Table 8) under a no choice situation

The genotypes Sough Local PIB-228 MBH-110 and D-1051-1 were less damaged

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

14

than SAR-57 BJ-104 and SAD-4031 Visual leaf damage rating was positively

correlated with leaf area (r=0 85) and dry weight consumed (r=O95) Leaf

area and dry weight consumed indifferent genotypes were also positively

correlated (r=087)

Leaf damage by Mythimna differed significantly in the hybrid trial

under field conditions The interesting feature of these data were that

hybrids based on lilA male sterile were less damaged than those based on

5141A and 5054A Similar indications of reduced damage of leaves in hybrids

based on IliA have also been obtained for Myllocerus damage at Hissar

(Unpublished data)

A number of reports have indicated the existence of varietal resistance

in wheat rice maize and sorghum under field conditions (Sharma and Davies

1982) Under field conditions the extent of damage is influenced by (a)the

amount of hiding space available to the larvae(b) the plant characteristics

(height tillering and leaf canopy) and (c) the positionlocation of the

cultivar in the field The insect damage tends to be higher in the center

of the field and inareas with surface mulch (or any other plant material

lying on the ground) The dwarf genotypes having more tillers suffer

heavier damage than tall and less tillering genotypes Inaddition the

genotypic differences in susceptibility tend to narrow down with the increase

in (a) insect pressure and (b)exposure time Under these situations we

must look for genotypic resistance under controlled conditions The

resistance parameters should include (a) leaf damage (b) larval survival

and rate of development and (c) fecundity All cases of field resistance

should be put to test for these parameters under controlled conditions

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

15

7 CONTROL

71 AGRONOMIC PRACTICES

During kharif 1980 population of Mythimna larvae and leaf damage were

recorded inan experiment having 4 weeding treatments (weed-free atrazine

05 kgha + one hand weeding one hand weeding and weedy check) in four

pearl millet cultivars (Ex-bornu G-73-K-77 BJ-104 and IVS-AX75) Each

treatment was replicated thrice ina split-plot design The number of

Mythimna iarvae were counted per square meter In the center of each plot

The treatments were also rated visuallly for leaf damage on 1-5 scale The

larval population and leaf damage indifferent treatments were compared

with weed dry weight and grain yield by computing simple correlations

The extent of Mythimna damage in two cultivars (BK-560 and ICH-118)

sown in eight plant spacings (llOxllO 80x80 100x40 I0Ox20 lOOxlO 50x20

50x1O and 50x40 cm) was evaluated for leaf damage during kharif 1981 at

Anantapur inan outbreak situation Each treatment was replicated four times

In a split plot design with spacings as the main plots Leaf damage ineach

plot was rated on 1-5 scale The extent of leaf damage was compared with the

plant densities

Larval population and leaf damage were greater inplots having heavy

weed population (Fig7) Among the cultivars tested Ex-bornu appeared

to be less damaged than GAM-75-K-77 and BJ-104 Similar indications have

also been obtained from resistance screening experiments (Table 8) The

grain yield was negatively correlated with larval population (r =-069)

leaf damage (r = -071) and weed dry weight (r =-094) Larval population

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

72

16

was positively correlated with weed dry weight (r = 067) and crop damage

(r=O63) At Anantpur plant population was found to be positively

correlated with Mythimna damage (r=024) However the correlation coefficient was

quite low because this happened to be an outbreak situation

Clean cultivation may be one of the important factors that would

reduce Mythimna damage This deprives the larvae of their hiding space

during day time and possibly exposes them to a number of parasites and

predators The weeds may also be more attractive to the larvae We need

to look more carefully into the various apects of crop husbandry which

could be manipulated to the disadvantage of the insect without involving

additional costs

ANTIFEEDANTS

Neem (Azadirachta indica) kernel and shell powider and their alcoholic

extracts were evaluated for their phagodetterrent effect against Mythimna

larvae The shell and kernel of one kg fruits were separated and

powdered in a pestle and mortair 250g of each powder were passed through a 60 mesh

sieve and then extracted in 95 ethyl alcohol on a hot water bath for

12 hours The alcoholic extracts were filtered through Whatman filter

paper (No1) The filtrate was evaporated on a hot water bath The

shell powder yiclded a reddish brown sticky material and kernel powder

a yellowish brown oil like material

The shell and kernel powders were suspended in 10 ethyl alcohol

The alcoholic extracts were dissolved in 10 ml of ethyl alcohol and distilled

water was added to make up the volume to 100 m1O In free choice test the

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

17

shell powder and kernel powder were tested 1 and 2 glO0 ml and alcoholic

extracts 5 and ig100 ml In no-choice test both powders and alcoholic

extracts were tested at 1 concentration In the free choice test twenty-day-old

plants of BJ-104 (grown in 15x]5x]O cm plastic pots) were treated with different

concentrations Each pot had 5 plants Twenty larvae (3rd instar) were

released in each pot The number of larvae in each pot were counted at 244872

and 96 hr after release The plants were rated for leaf damage in each pot

after 96 hr In no-choice test the larvae were confined to the plants using

a glass chimney The larvae were removed after 24fhr Observations were

recorded on leaf area and dry weight of the plants Leaf area and dry

weight consumed by the larvae in treated pots was expressed as percent of

the control pots There were significant differences in larval distribution

and leaf damage under free choice situation (Table 9) The number of arvae

were minimum in pots treated with alcoholic extracts of shell and kernel

powder Under no choice conditions (TablelO) alcoholic extracts of shell

and kernel powder were most effective

The mixing of neem leaves with grains is an age old practice in India

Pruthl (1937) produced the first scientific data on the repellent action

of neem leaves against stored grain pests The demonstration of antifeedant

properties of neem against desert locust generated tremendous interest in

this plant (Pradhan et al 1962 Sinha and Gulati 1963 and Goyal et al

1971) The neem products are now known to disrupt moulting and act

as antifeedants (Gill and Lewis 1971 Leuschner 1972 Jacobson et al

1978 Schmutterer and Rembold 1980 and Sharma et al 1980) The neem

components also act as oviposition suppressant (Joshi and Sitaramaiah 1979)

In view of a number of active components isolated from neem there seem to be

8

18

a great potential for its use in future pest-management systems

SUMMARY

1 Mythimna separata damages sorghum and pearl-millet severely during

August-September Larvae remain active in the field during January-

April and June-December Over the past six years no moths have

been trapped during June while larvae have been observed 7-10 days

after initiation of monsoon rains during June

2 Its population can increase at a tremendous rate because of the high

fecundity of females The entire development from egg to adult takes

around 29-39 days

3 The maximum no of moths were caught during 1977 when the first outbreak

was experienced Light traps indicated peak activity during September

and the maximum larval activity was observed in August The trap catches

vary in different years and at different locations The maximum activity

of moths occurred during a period of lower or no rainfall preceded by a

2-4 week period of normalhigh rainfall moderate temperatures and high

humidity

4 Larval population was much lower in farmers fields and unsprayed

alfisols than in sprayed alfisols and vertisols and unsprayed vertisols

5 A number of hymenopteran dipteran and mermithid parasites regulated

the Mythimna population to some extent Larval parasitization increased

from June to October

19

6 The extent of larval parasitization was much higher in sorghum than

In pearl-millet The sex ratio tended to be more in favour of females

in pearl-millet than in sorghum This possibly resulted in large

scale defoliation in pearl-millet as compared with sorghum

at a number of places in recent7 A number of outbreaks have occurred

years The problem seems to have been accentuated with an increase

in irrigated area continuous cultivation introduction of newer

high yielding cultivars and increased fertilizer use

8 It is a voracious and polyphagous pest of a number of plant species

There seem to be some indications of host preference among the plant

insect damage also differs in differentspecies it feeds upon The

genotypes in 6ereals However the extent of damage depends upon the

Instances of field resistance needinsect population and exposure time

to be varified under no-choice conditions

to reduce insect9 Clean cultivation and lower plant population may help

damage to sortie extent

properties as phagodeterrents10 Plant products from neem exhibit useful

our pest control armoury inThis may form an important component of

the future

20

LOOKING AHEAD

Studies on its biology in different agroclimatic zones should

be carried out particularly in relation to seasonal activity

maximum and minimum activity periods mode of carryover and

source of initial infestations

2 A population monitoring grid should be set up in the Indian

sub-continent The population monitoring may be carried out

through light traps mollases and pheromone baited traps

These data should be verified through Deriodic field observashy

tions The data should be recorded in a manner so that it

could be used in systems modelling and pest forecasting

3 The source of initial infestatio-s and factors leading to outbreaks

should be studied in different aqroclimatic zones In this the

role of natural enemies crops and crop combinations and the

possibly of different cultivars need to be looked into The

possible movement and utilizatior of efficient natural enemies

should be actively persued

4 Population management involving host plant resistance natural

enemies agronomic practices (clean cultivation and lower plant

population fe-rtilizer use tillage) antifeedants and

occasional ue of insecticidei Ahould be carefully investigated

evaluated and nut up as a balanced control approach

REFERENCES

Asahina S (1968) Insect dispersal as observed by a weathership on the

North Western Pacific Page 106 in XIII International Congress of

Entomology Moscow 2-9 Aug 1968

Avasthy PN and Chaudhary JP (1965) Biology and control of armyworm

Pseudaleti3 unipuncta Haw Indian Sugarcane Journal 9249-251

Bhatnagar VS and Davies JC(1979) Insect trap studies at ICRISAT Center

Progress Report (Cropping Entomology-2) International Crops Research

Institute for the Semi-Arid Tropics ICRISAT Hyderabad India 8 pp

Bhatnagar VS and Davies JC(1978) Factors affecting population of

gram pod borer Heliothis armigera (Hubner) at Patancheru Andhra Pradesh

Bulletin of Entomology 1952-64

Bindra OS amp Singh J(1973) Bionomics of the armyworm Mythimna separata

(Walker) (LepidopteraNoctuidae) at Ludhiana Punjab The Indian Journal

of Agricultural Sciences 48299-303

Butani DK(1955) ontrol of an outbreak of the armyworm (Cirphis unipuncta

Haw) on sugarcane at Pusa Bihar 1953 Indian Journal of Entomology

17133-136

Butter NS(1978) Apateles ruficrus Haliday - an efficient parasite of

armyworm (Mythimna seprata (Walker) on wheat Science and Culture

44181-182

COen Rui-lo Leo Chao-Shen Liu Tseng-ye Li Mien-chung and Sien Nlen-ying

(1965) Studies on the source of early spring generations of the armyworm

Leucania separata Walker in the Kirin Province I Studies on the

original ground of immigrant moths Acta Phytophylacica Sinica 449-58

Chin TS(1979) The relations of population dynamics of the armyworm

Leucania separata Walker to relative humidity and rainfall Acta

Entomologica Sinica 22404-412

22

Gill JS and Lewis CT(197) Systematic action of an Insect feeding

detterent Nature (London) 2324Q2-403

Gopinadhan PB and Kushwaha KS(1978) Population trend of the armyworm

Mythimna separata Walker (Leoldoptera Noctuidae) under the Influence of

key ablotic and biotic factors In All India Workshop on Population

Ecology in relation to insects of gconomic Importance Jan 18-20 1978

Bangalore India

Goyal RS Gulati KC Sarup P Kidwal MA and Singh DS(1971)

Biological activity of various alcoholic extractives and isolates

of neem (Azadirachta Indica) seed cake against Rhopaios phum nympheae

(Linn) and Schistocorea gregaria Forsk Indian Journal of Entomology

32242-252

Grist DH and Lever RJAW(1969) Pests of Rice London UK

Longmans Green and Co Ltd 520 pp

Hsia TS Tsai SM and Ten HS(1963) Studies of the regularity of

oatbreak of the oriental armyworm Leucania sepgrata Walker II

Observations on the migratory activity of moths across the Chili gulf

an Yellow sea of China Acta Entomologica Sinica 12552-564

Hwang Guan-huel and How Wu-wel (1966) Studies on the flight of armyworm

moth (Leucanla separate Walker) I Flight duration and wing beat

frequency Acta Entomologica Slnica 1596-104

Jacobson M Reed OK Crystal MM Moreno DS and Soderstorm EL

(1978) Chemistry and biological activity of Insect feeding detterents

from certain weed and crop plants Entomologla Experimentalis et

Applicata 24448-457

Joshl BG and Sitaramalah S(1979) Neem Kernal as an ovipositional

repellent for Spodoptera litura (F) mothsPhytoparasltica 7199-202

23

Kalode MB Varma A Yadav CP amp Israel P(197) Feeding reaction

of armyworm (Cirphis compta Moore) larvae fed on some cultivated and

wild plants Indian Journal of Agricultural Sciences 41568-572

Koyama J(1966) The relation between the outbreak of armyworms (Leucania

separata Walker) and the richly nitrogeneous manured cultivation of

rice plants Journal of Applied Entomology and Zoology 10123-128

Koyama J(0970) Some considerations on the chronological records of

outbreaks of the armyworm (Leucania separata Walker) Japanese Journal

of Applied Entomology and Zoology 1457-63

Leuschner K(972) Effect of an unknown plant substance on a shield bug

Naturwissenchaften 59217-218

Li (Kuang-po) Wong Hun Chao (Shung-Jin) Chain (Shu-Ching) and Lin (Jung-You)

(1963) Field studies on the effect of microclimate on the populatdon

density of the armyworm Acta Phytophylacica Sinica 257-62

Li (Kuang-Po) Wong (Hong-hsiang) and Woo (Wen-sei)(1965) Route of the

seasonal migration of the oriental armyworm moth in the eastern part of

China as indicated by a three year result of releasing and recapturing

marked moths TCNo2 pp 101 to 110

Lin (Chang-Shan) (1963) Studies on the regularity of the outbreak of the oriental

armyworm (Leucania separata Walker) IV An analysis of the metereo-physlcal

conditions during the descending movement of the long distance migration of

the oriental armyworm moth Acta Phytophylacica Sinica 2111-122

Lin (Chang-Shan) and Chang (J Tsun-ping)(1964) Studies on the regularities of the

outbreak of the oriental armyworm (Leucania separata Walker)V A model for

seasonal long distance migration of the oriental armyworm Acta Phytophylacica

Sinica 393-100

Lin (Chang-Shan) Sun (Chin-ju) Chen (Rui Lo) and Chang (J Tsun-ping)(1963)

Studies on the regularity of the outbreak of the oriental armyworm

Leucania separata Walker I The early spring orientation of the oriental

armyworm moths and its relation to winds Acta Entomologica Sinica 12243-261

Ma SC(1979) Insect Ecology in the Peoples Republic of China Acta

Entomologica Sinica 22257-266

24

Mohyuddln AI amp Shah S(1977) Biological control of Mythlmna separata

(Lep Noctuldae) in New Zealand and its bearing on biological control

strategy Entomophaga 22331-333

Nagano M Yoshioka T Itayama T Nishino T Yamaguchi T and Nagata Y(1972)

Forecasting of the armyworm Leucaiia (Mythimna) separata Walker in grassland

I Outbreak in 1970 Proceedings of the Association for Plant Protection

Kyushu 1788-90

Neelgund YF and Mathad SB(1972) Nuclear polyhedrosis of Pseudaletia

separata (Lepidoptera Noctuidae) Annals of the Entomological Society

of America 65763-764

Oku T amp Kobayashi T(0974) Early summer outbreaks of the oriental

armyworm Mythimna separata Walker in the Tohoku District and possible

causative factors (LepidopteraNoctuidae) Applied Entomology and

Zoology 9238-246

Pradhan S Jotwani MG and Rai BK (1962) The neem seed detterent to

locusts Indian Farming 127-11

Pruthi jHS(1937) Report of the Imperial Entomologist In Scientific

report of Agricultural Research Institute New Delhi 1935-36

Puttarudriah M amp Usman S(1957) Flood causes armyworm outbreak Mysore

Agricultural Journal 32124-131

Schmutterer H and Rembold H(1980) Performance of some pure fractions

extracted from seed of Azadirachta indica on feeding activity and

metamorphasis of Epilachna varivestis (Co Coccinellidae) Zeitschrift

fur Angewandte Entomologie 89179-188

Sharma GK Ch Czoppelt and Rembold H(1980) Further evidence of insect

growth disruption by neem seed fractions Zeitschrift fur Angewandte

Entomologie 90439-444

Sharma HC and Davies JC(1982) The oriental armyworm Mythimna separata

Distribution biology and control - A literature review Tropical Pest

Management (submitted)

25

Simmonds FJ(1976) Some recent puzzles in biological control

Entomophaga 21327-332

Simmonds FJ amp Bonnett FD(1977) Biological control of Agriciltural

pests Proceedings of the International Congress of Entomology

15464-472

Sinha NP and Gulati KC(1963) Neem (Azadirachta indica) seed cake

as a source of pest control chemicals Bulletin of Regional Research

Laboratory Jammu India 176-177

Verma AN amp Khurana AD (1971) Incidence of armyworm Pseudaletia

separata Walker in different dwarf wheat varieties Haryana

Agricultural University Journal of Research 120-23

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

19

6 The extent of larval parasitization was much higher in sorghum than

In pearl-millet The sex ratio tended to be more in favour of females

in pearl-millet than in sorghum This possibly resulted in large

scale defoliation in pearl-millet as compared with sorghum

at a number of places in recent7 A number of outbreaks have occurred

years The problem seems to have been accentuated with an increase

in irrigated area continuous cultivation introduction of newer

high yielding cultivars and increased fertilizer use

8 It is a voracious and polyphagous pest of a number of plant species

There seem to be some indications of host preference among the plant

insect damage also differs in differentspecies it feeds upon The

genotypes in 6ereals However the extent of damage depends upon the

Instances of field resistance needinsect population and exposure time

to be varified under no-choice conditions

to reduce insect9 Clean cultivation and lower plant population may help

damage to sortie extent

properties as phagodeterrents10 Plant products from neem exhibit useful

our pest control armoury inThis may form an important component of

the future

20

LOOKING AHEAD

Studies on its biology in different agroclimatic zones should

be carried out particularly in relation to seasonal activity

maximum and minimum activity periods mode of carryover and

source of initial infestations

2 A population monitoring grid should be set up in the Indian

sub-continent The population monitoring may be carried out

through light traps mollases and pheromone baited traps

These data should be verified through Deriodic field observashy

tions The data should be recorded in a manner so that it

could be used in systems modelling and pest forecasting

3 The source of initial infestatio-s and factors leading to outbreaks

should be studied in different aqroclimatic zones In this the

role of natural enemies crops and crop combinations and the

possibly of different cultivars need to be looked into The

possible movement and utilizatior of efficient natural enemies

should be actively persued

4 Population management involving host plant resistance natural

enemies agronomic practices (clean cultivation and lower plant

population fe-rtilizer use tillage) antifeedants and

occasional ue of insecticidei Ahould be carefully investigated

evaluated and nut up as a balanced control approach

REFERENCES

Asahina S (1968) Insect dispersal as observed by a weathership on the

North Western Pacific Page 106 in XIII International Congress of

Entomology Moscow 2-9 Aug 1968

Avasthy PN and Chaudhary JP (1965) Biology and control of armyworm

Pseudaleti3 unipuncta Haw Indian Sugarcane Journal 9249-251

Bhatnagar VS and Davies JC(1979) Insect trap studies at ICRISAT Center

Progress Report (Cropping Entomology-2) International Crops Research

Institute for the Semi-Arid Tropics ICRISAT Hyderabad India 8 pp

Bhatnagar VS and Davies JC(1978) Factors affecting population of

gram pod borer Heliothis armigera (Hubner) at Patancheru Andhra Pradesh

Bulletin of Entomology 1952-64

Bindra OS amp Singh J(1973) Bionomics of the armyworm Mythimna separata

(Walker) (LepidopteraNoctuidae) at Ludhiana Punjab The Indian Journal

of Agricultural Sciences 48299-303

Butani DK(1955) ontrol of an outbreak of the armyworm (Cirphis unipuncta

Haw) on sugarcane at Pusa Bihar 1953 Indian Journal of Entomology

17133-136

Butter NS(1978) Apateles ruficrus Haliday - an efficient parasite of

armyworm (Mythimna seprata (Walker) on wheat Science and Culture

44181-182

COen Rui-lo Leo Chao-Shen Liu Tseng-ye Li Mien-chung and Sien Nlen-ying

(1965) Studies on the source of early spring generations of the armyworm

Leucania separata Walker in the Kirin Province I Studies on the

original ground of immigrant moths Acta Phytophylacica Sinica 449-58

Chin TS(1979) The relations of population dynamics of the armyworm

Leucania separata Walker to relative humidity and rainfall Acta

Entomologica Sinica 22404-412

22

Gill JS and Lewis CT(197) Systematic action of an Insect feeding

detterent Nature (London) 2324Q2-403

Gopinadhan PB and Kushwaha KS(1978) Population trend of the armyworm

Mythimna separata Walker (Leoldoptera Noctuidae) under the Influence of

key ablotic and biotic factors In All India Workshop on Population

Ecology in relation to insects of gconomic Importance Jan 18-20 1978

Bangalore India

Goyal RS Gulati KC Sarup P Kidwal MA and Singh DS(1971)

Biological activity of various alcoholic extractives and isolates

of neem (Azadirachta Indica) seed cake against Rhopaios phum nympheae

(Linn) and Schistocorea gregaria Forsk Indian Journal of Entomology

32242-252

Grist DH and Lever RJAW(1969) Pests of Rice London UK

Longmans Green and Co Ltd 520 pp

Hsia TS Tsai SM and Ten HS(1963) Studies of the regularity of

oatbreak of the oriental armyworm Leucania sepgrata Walker II

Observations on the migratory activity of moths across the Chili gulf

an Yellow sea of China Acta Entomologica Sinica 12552-564

Hwang Guan-huel and How Wu-wel (1966) Studies on the flight of armyworm

moth (Leucanla separate Walker) I Flight duration and wing beat

frequency Acta Entomologica Slnica 1596-104

Jacobson M Reed OK Crystal MM Moreno DS and Soderstorm EL

(1978) Chemistry and biological activity of Insect feeding detterents

from certain weed and crop plants Entomologla Experimentalis et

Applicata 24448-457

Joshl BG and Sitaramalah S(1979) Neem Kernal as an ovipositional

repellent for Spodoptera litura (F) mothsPhytoparasltica 7199-202

23

Kalode MB Varma A Yadav CP amp Israel P(197) Feeding reaction

of armyworm (Cirphis compta Moore) larvae fed on some cultivated and

wild plants Indian Journal of Agricultural Sciences 41568-572

Koyama J(1966) The relation between the outbreak of armyworms (Leucania

separata Walker) and the richly nitrogeneous manured cultivation of

rice plants Journal of Applied Entomology and Zoology 10123-128

Koyama J(0970) Some considerations on the chronological records of

outbreaks of the armyworm (Leucania separata Walker) Japanese Journal

of Applied Entomology and Zoology 1457-63

Leuschner K(972) Effect of an unknown plant substance on a shield bug

Naturwissenchaften 59217-218

Li (Kuang-po) Wong Hun Chao (Shung-Jin) Chain (Shu-Ching) and Lin (Jung-You)

(1963) Field studies on the effect of microclimate on the populatdon

density of the armyworm Acta Phytophylacica Sinica 257-62

Li (Kuang-Po) Wong (Hong-hsiang) and Woo (Wen-sei)(1965) Route of the

seasonal migration of the oriental armyworm moth in the eastern part of

China as indicated by a three year result of releasing and recapturing

marked moths TCNo2 pp 101 to 110

Lin (Chang-Shan) (1963) Studies on the regularity of the outbreak of the oriental

armyworm (Leucania separata Walker) IV An analysis of the metereo-physlcal

conditions during the descending movement of the long distance migration of

the oriental armyworm moth Acta Phytophylacica Sinica 2111-122

Lin (Chang-Shan) and Chang (J Tsun-ping)(1964) Studies on the regularities of the

outbreak of the oriental armyworm (Leucania separata Walker)V A model for

seasonal long distance migration of the oriental armyworm Acta Phytophylacica

Sinica 393-100

Lin (Chang-Shan) Sun (Chin-ju) Chen (Rui Lo) and Chang (J Tsun-ping)(1963)

Studies on the regularity of the outbreak of the oriental armyworm

Leucania separata Walker I The early spring orientation of the oriental

armyworm moths and its relation to winds Acta Entomologica Sinica 12243-261

Ma SC(1979) Insect Ecology in the Peoples Republic of China Acta

Entomologica Sinica 22257-266

24

Mohyuddln AI amp Shah S(1977) Biological control of Mythlmna separata

(Lep Noctuldae) in New Zealand and its bearing on biological control

strategy Entomophaga 22331-333

Nagano M Yoshioka T Itayama T Nishino T Yamaguchi T and Nagata Y(1972)

Forecasting of the armyworm Leucaiia (Mythimna) separata Walker in grassland

I Outbreak in 1970 Proceedings of the Association for Plant Protection

Kyushu 1788-90

Neelgund YF and Mathad SB(1972) Nuclear polyhedrosis of Pseudaletia

separata (Lepidoptera Noctuidae) Annals of the Entomological Society

of America 65763-764

Oku T amp Kobayashi T(0974) Early summer outbreaks of the oriental

armyworm Mythimna separata Walker in the Tohoku District and possible

causative factors (LepidopteraNoctuidae) Applied Entomology and

Zoology 9238-246

Pradhan S Jotwani MG and Rai BK (1962) The neem seed detterent to

locusts Indian Farming 127-11

Pruthi jHS(1937) Report of the Imperial Entomologist In Scientific

report of Agricultural Research Institute New Delhi 1935-36

Puttarudriah M amp Usman S(1957) Flood causes armyworm outbreak Mysore

Agricultural Journal 32124-131

Schmutterer H and Rembold H(1980) Performance of some pure fractions

extracted from seed of Azadirachta indica on feeding activity and

metamorphasis of Epilachna varivestis (Co Coccinellidae) Zeitschrift

fur Angewandte Entomologie 89179-188

Sharma GK Ch Czoppelt and Rembold H(1980) Further evidence of insect

growth disruption by neem seed fractions Zeitschrift fur Angewandte

Entomologie 90439-444

Sharma HC and Davies JC(1982) The oriental armyworm Mythimna separata

Distribution biology and control - A literature review Tropical Pest

Management (submitted)

25

Simmonds FJ(1976) Some recent puzzles in biological control

Entomophaga 21327-332

Simmonds FJ amp Bonnett FD(1977) Biological control of Agriciltural

pests Proceedings of the International Congress of Entomology

15464-472

Sinha NP and Gulati KC(1963) Neem (Azadirachta indica) seed cake

as a source of pest control chemicals Bulletin of Regional Research

Laboratory Jammu India 176-177

Verma AN amp Khurana AD (1971) Incidence of armyworm Pseudaletia

separata Walker in different dwarf wheat varieties Haryana

Agricultural University Journal of Research 120-23

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

20

LOOKING AHEAD

Studies on its biology in different agroclimatic zones should

be carried out particularly in relation to seasonal activity

maximum and minimum activity periods mode of carryover and

source of initial infestations

2 A population monitoring grid should be set up in the Indian

sub-continent The population monitoring may be carried out

through light traps mollases and pheromone baited traps

These data should be verified through Deriodic field observashy

tions The data should be recorded in a manner so that it

could be used in systems modelling and pest forecasting

3 The source of initial infestatio-s and factors leading to outbreaks

should be studied in different aqroclimatic zones In this the

role of natural enemies crops and crop combinations and the

possibly of different cultivars need to be looked into The

possible movement and utilizatior of efficient natural enemies

should be actively persued

4 Population management involving host plant resistance natural

enemies agronomic practices (clean cultivation and lower plant

population fe-rtilizer use tillage) antifeedants and

occasional ue of insecticidei Ahould be carefully investigated

evaluated and nut up as a balanced control approach

REFERENCES

Asahina S (1968) Insect dispersal as observed by a weathership on the

North Western Pacific Page 106 in XIII International Congress of

Entomology Moscow 2-9 Aug 1968

Avasthy PN and Chaudhary JP (1965) Biology and control of armyworm

Pseudaleti3 unipuncta Haw Indian Sugarcane Journal 9249-251

Bhatnagar VS and Davies JC(1979) Insect trap studies at ICRISAT Center

Progress Report (Cropping Entomology-2) International Crops Research

Institute for the Semi-Arid Tropics ICRISAT Hyderabad India 8 pp

Bhatnagar VS and Davies JC(1978) Factors affecting population of

gram pod borer Heliothis armigera (Hubner) at Patancheru Andhra Pradesh

Bulletin of Entomology 1952-64

Bindra OS amp Singh J(1973) Bionomics of the armyworm Mythimna separata

(Walker) (LepidopteraNoctuidae) at Ludhiana Punjab The Indian Journal

of Agricultural Sciences 48299-303

Butani DK(1955) ontrol of an outbreak of the armyworm (Cirphis unipuncta

Haw) on sugarcane at Pusa Bihar 1953 Indian Journal of Entomology

17133-136

Butter NS(1978) Apateles ruficrus Haliday - an efficient parasite of

armyworm (Mythimna seprata (Walker) on wheat Science and Culture

44181-182

COen Rui-lo Leo Chao-Shen Liu Tseng-ye Li Mien-chung and Sien Nlen-ying

(1965) Studies on the source of early spring generations of the armyworm

Leucania separata Walker in the Kirin Province I Studies on the

original ground of immigrant moths Acta Phytophylacica Sinica 449-58

Chin TS(1979) The relations of population dynamics of the armyworm

Leucania separata Walker to relative humidity and rainfall Acta

Entomologica Sinica 22404-412

22

Gill JS and Lewis CT(197) Systematic action of an Insect feeding

detterent Nature (London) 2324Q2-403

Gopinadhan PB and Kushwaha KS(1978) Population trend of the armyworm

Mythimna separata Walker (Leoldoptera Noctuidae) under the Influence of

key ablotic and biotic factors In All India Workshop on Population

Ecology in relation to insects of gconomic Importance Jan 18-20 1978

Bangalore India

Goyal RS Gulati KC Sarup P Kidwal MA and Singh DS(1971)

Biological activity of various alcoholic extractives and isolates

of neem (Azadirachta Indica) seed cake against Rhopaios phum nympheae

(Linn) and Schistocorea gregaria Forsk Indian Journal of Entomology

32242-252

Grist DH and Lever RJAW(1969) Pests of Rice London UK

Longmans Green and Co Ltd 520 pp

Hsia TS Tsai SM and Ten HS(1963) Studies of the regularity of

oatbreak of the oriental armyworm Leucania sepgrata Walker II

Observations on the migratory activity of moths across the Chili gulf

an Yellow sea of China Acta Entomologica Sinica 12552-564

Hwang Guan-huel and How Wu-wel (1966) Studies on the flight of armyworm

moth (Leucanla separate Walker) I Flight duration and wing beat

frequency Acta Entomologica Slnica 1596-104

Jacobson M Reed OK Crystal MM Moreno DS and Soderstorm EL

(1978) Chemistry and biological activity of Insect feeding detterents

from certain weed and crop plants Entomologla Experimentalis et

Applicata 24448-457

Joshl BG and Sitaramalah S(1979) Neem Kernal as an ovipositional

repellent for Spodoptera litura (F) mothsPhytoparasltica 7199-202

23

Kalode MB Varma A Yadav CP amp Israel P(197) Feeding reaction

of armyworm (Cirphis compta Moore) larvae fed on some cultivated and

wild plants Indian Journal of Agricultural Sciences 41568-572

Koyama J(1966) The relation between the outbreak of armyworms (Leucania

separata Walker) and the richly nitrogeneous manured cultivation of

rice plants Journal of Applied Entomology and Zoology 10123-128

Koyama J(0970) Some considerations on the chronological records of

outbreaks of the armyworm (Leucania separata Walker) Japanese Journal

of Applied Entomology and Zoology 1457-63

Leuschner K(972) Effect of an unknown plant substance on a shield bug

Naturwissenchaften 59217-218

Li (Kuang-po) Wong Hun Chao (Shung-Jin) Chain (Shu-Ching) and Lin (Jung-You)

(1963) Field studies on the effect of microclimate on the populatdon

density of the armyworm Acta Phytophylacica Sinica 257-62

Li (Kuang-Po) Wong (Hong-hsiang) and Woo (Wen-sei)(1965) Route of the

seasonal migration of the oriental armyworm moth in the eastern part of

China as indicated by a three year result of releasing and recapturing

marked moths TCNo2 pp 101 to 110

Lin (Chang-Shan) (1963) Studies on the regularity of the outbreak of the oriental

armyworm (Leucania separata Walker) IV An analysis of the metereo-physlcal

conditions during the descending movement of the long distance migration of

the oriental armyworm moth Acta Phytophylacica Sinica 2111-122

Lin (Chang-Shan) and Chang (J Tsun-ping)(1964) Studies on the regularities of the

outbreak of the oriental armyworm (Leucania separata Walker)V A model for

seasonal long distance migration of the oriental armyworm Acta Phytophylacica

Sinica 393-100

Lin (Chang-Shan) Sun (Chin-ju) Chen (Rui Lo) and Chang (J Tsun-ping)(1963)

Studies on the regularity of the outbreak of the oriental armyworm

Leucania separata Walker I The early spring orientation of the oriental

armyworm moths and its relation to winds Acta Entomologica Sinica 12243-261

Ma SC(1979) Insect Ecology in the Peoples Republic of China Acta

Entomologica Sinica 22257-266

24

Mohyuddln AI amp Shah S(1977) Biological control of Mythlmna separata

(Lep Noctuldae) in New Zealand and its bearing on biological control

strategy Entomophaga 22331-333

Nagano M Yoshioka T Itayama T Nishino T Yamaguchi T and Nagata Y(1972)

Forecasting of the armyworm Leucaiia (Mythimna) separata Walker in grassland

I Outbreak in 1970 Proceedings of the Association for Plant Protection

Kyushu 1788-90

Neelgund YF and Mathad SB(1972) Nuclear polyhedrosis of Pseudaletia

separata (Lepidoptera Noctuidae) Annals of the Entomological Society

of America 65763-764

Oku T amp Kobayashi T(0974) Early summer outbreaks of the oriental

armyworm Mythimna separata Walker in the Tohoku District and possible

causative factors (LepidopteraNoctuidae) Applied Entomology and

Zoology 9238-246

Pradhan S Jotwani MG and Rai BK (1962) The neem seed detterent to

locusts Indian Farming 127-11

Pruthi jHS(1937) Report of the Imperial Entomologist In Scientific

report of Agricultural Research Institute New Delhi 1935-36

Puttarudriah M amp Usman S(1957) Flood causes armyworm outbreak Mysore

Agricultural Journal 32124-131

Schmutterer H and Rembold H(1980) Performance of some pure fractions

extracted from seed of Azadirachta indica on feeding activity and

metamorphasis of Epilachna varivestis (Co Coccinellidae) Zeitschrift

fur Angewandte Entomologie 89179-188

Sharma GK Ch Czoppelt and Rembold H(1980) Further evidence of insect

growth disruption by neem seed fractions Zeitschrift fur Angewandte

Entomologie 90439-444

Sharma HC and Davies JC(1982) The oriental armyworm Mythimna separata

Distribution biology and control - A literature review Tropical Pest

Management (submitted)

25

Simmonds FJ(1976) Some recent puzzles in biological control

Entomophaga 21327-332

Simmonds FJ amp Bonnett FD(1977) Biological control of Agriciltural

pests Proceedings of the International Congress of Entomology

15464-472

Sinha NP and Gulati KC(1963) Neem (Azadirachta indica) seed cake

as a source of pest control chemicals Bulletin of Regional Research

Laboratory Jammu India 176-177

Verma AN amp Khurana AD (1971) Incidence of armyworm Pseudaletia

separata Walker in different dwarf wheat varieties Haryana

Agricultural University Journal of Research 120-23

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

REFERENCES

Asahina S (1968) Insect dispersal as observed by a weathership on the

North Western Pacific Page 106 in XIII International Congress of

Entomology Moscow 2-9 Aug 1968

Avasthy PN and Chaudhary JP (1965) Biology and control of armyworm

Pseudaleti3 unipuncta Haw Indian Sugarcane Journal 9249-251

Bhatnagar VS and Davies JC(1979) Insect trap studies at ICRISAT Center

Progress Report (Cropping Entomology-2) International Crops Research

Institute for the Semi-Arid Tropics ICRISAT Hyderabad India 8 pp

Bhatnagar VS and Davies JC(1978) Factors affecting population of

gram pod borer Heliothis armigera (Hubner) at Patancheru Andhra Pradesh

Bulletin of Entomology 1952-64

Bindra OS amp Singh J(1973) Bionomics of the armyworm Mythimna separata

(Walker) (LepidopteraNoctuidae) at Ludhiana Punjab The Indian Journal

of Agricultural Sciences 48299-303

Butani DK(1955) ontrol of an outbreak of the armyworm (Cirphis unipuncta

Haw) on sugarcane at Pusa Bihar 1953 Indian Journal of Entomology

17133-136

Butter NS(1978) Apateles ruficrus Haliday - an efficient parasite of

armyworm (Mythimna seprata (Walker) on wheat Science and Culture

44181-182

COen Rui-lo Leo Chao-Shen Liu Tseng-ye Li Mien-chung and Sien Nlen-ying

(1965) Studies on the source of early spring generations of the armyworm

Leucania separata Walker in the Kirin Province I Studies on the

original ground of immigrant moths Acta Phytophylacica Sinica 449-58

Chin TS(1979) The relations of population dynamics of the armyworm

Leucania separata Walker to relative humidity and rainfall Acta

Entomologica Sinica 22404-412

22

Gill JS and Lewis CT(197) Systematic action of an Insect feeding

detterent Nature (London) 2324Q2-403

Gopinadhan PB and Kushwaha KS(1978) Population trend of the armyworm

Mythimna separata Walker (Leoldoptera Noctuidae) under the Influence of

key ablotic and biotic factors In All India Workshop on Population

Ecology in relation to insects of gconomic Importance Jan 18-20 1978

Bangalore India

Goyal RS Gulati KC Sarup P Kidwal MA and Singh DS(1971)

Biological activity of various alcoholic extractives and isolates

of neem (Azadirachta Indica) seed cake against Rhopaios phum nympheae

(Linn) and Schistocorea gregaria Forsk Indian Journal of Entomology

32242-252

Grist DH and Lever RJAW(1969) Pests of Rice London UK

Longmans Green and Co Ltd 520 pp

Hsia TS Tsai SM and Ten HS(1963) Studies of the regularity of

oatbreak of the oriental armyworm Leucania sepgrata Walker II

Observations on the migratory activity of moths across the Chili gulf

an Yellow sea of China Acta Entomologica Sinica 12552-564

Hwang Guan-huel and How Wu-wel (1966) Studies on the flight of armyworm

moth (Leucanla separate Walker) I Flight duration and wing beat

frequency Acta Entomologica Slnica 1596-104

Jacobson M Reed OK Crystal MM Moreno DS and Soderstorm EL

(1978) Chemistry and biological activity of Insect feeding detterents

from certain weed and crop plants Entomologla Experimentalis et

Applicata 24448-457

Joshl BG and Sitaramalah S(1979) Neem Kernal as an ovipositional

repellent for Spodoptera litura (F) mothsPhytoparasltica 7199-202

23

Kalode MB Varma A Yadav CP amp Israel P(197) Feeding reaction

of armyworm (Cirphis compta Moore) larvae fed on some cultivated and

wild plants Indian Journal of Agricultural Sciences 41568-572

Koyama J(1966) The relation between the outbreak of armyworms (Leucania

separata Walker) and the richly nitrogeneous manured cultivation of

rice plants Journal of Applied Entomology and Zoology 10123-128

Koyama J(0970) Some considerations on the chronological records of

outbreaks of the armyworm (Leucania separata Walker) Japanese Journal

of Applied Entomology and Zoology 1457-63

Leuschner K(972) Effect of an unknown plant substance on a shield bug

Naturwissenchaften 59217-218

Li (Kuang-po) Wong Hun Chao (Shung-Jin) Chain (Shu-Ching) and Lin (Jung-You)

(1963) Field studies on the effect of microclimate on the populatdon

density of the armyworm Acta Phytophylacica Sinica 257-62

Li (Kuang-Po) Wong (Hong-hsiang) and Woo (Wen-sei)(1965) Route of the

seasonal migration of the oriental armyworm moth in the eastern part of

China as indicated by a three year result of releasing and recapturing

marked moths TCNo2 pp 101 to 110

Lin (Chang-Shan) (1963) Studies on the regularity of the outbreak of the oriental

armyworm (Leucania separata Walker) IV An analysis of the metereo-physlcal

conditions during the descending movement of the long distance migration of

the oriental armyworm moth Acta Phytophylacica Sinica 2111-122

Lin (Chang-Shan) and Chang (J Tsun-ping)(1964) Studies on the regularities of the

outbreak of the oriental armyworm (Leucania separata Walker)V A model for

seasonal long distance migration of the oriental armyworm Acta Phytophylacica

Sinica 393-100

Lin (Chang-Shan) Sun (Chin-ju) Chen (Rui Lo) and Chang (J Tsun-ping)(1963)

Studies on the regularity of the outbreak of the oriental armyworm

Leucania separata Walker I The early spring orientation of the oriental

armyworm moths and its relation to winds Acta Entomologica Sinica 12243-261

Ma SC(1979) Insect Ecology in the Peoples Republic of China Acta

Entomologica Sinica 22257-266

24

Mohyuddln AI amp Shah S(1977) Biological control of Mythlmna separata

(Lep Noctuldae) in New Zealand and its bearing on biological control

strategy Entomophaga 22331-333

Nagano M Yoshioka T Itayama T Nishino T Yamaguchi T and Nagata Y(1972)

Forecasting of the armyworm Leucaiia (Mythimna) separata Walker in grassland

I Outbreak in 1970 Proceedings of the Association for Plant Protection

Kyushu 1788-90

Neelgund YF and Mathad SB(1972) Nuclear polyhedrosis of Pseudaletia

separata (Lepidoptera Noctuidae) Annals of the Entomological Society

of America 65763-764

Oku T amp Kobayashi T(0974) Early summer outbreaks of the oriental

armyworm Mythimna separata Walker in the Tohoku District and possible

causative factors (LepidopteraNoctuidae) Applied Entomology and

Zoology 9238-246

Pradhan S Jotwani MG and Rai BK (1962) The neem seed detterent to

locusts Indian Farming 127-11

Pruthi jHS(1937) Report of the Imperial Entomologist In Scientific

report of Agricultural Research Institute New Delhi 1935-36

Puttarudriah M amp Usman S(1957) Flood causes armyworm outbreak Mysore

Agricultural Journal 32124-131

Schmutterer H and Rembold H(1980) Performance of some pure fractions

extracted from seed of Azadirachta indica on feeding activity and

metamorphasis of Epilachna varivestis (Co Coccinellidae) Zeitschrift

fur Angewandte Entomologie 89179-188

Sharma GK Ch Czoppelt and Rembold H(1980) Further evidence of insect

growth disruption by neem seed fractions Zeitschrift fur Angewandte

Entomologie 90439-444

Sharma HC and Davies JC(1982) The oriental armyworm Mythimna separata

Distribution biology and control - A literature review Tropical Pest

Management (submitted)

25

Simmonds FJ(1976) Some recent puzzles in biological control

Entomophaga 21327-332

Simmonds FJ amp Bonnett FD(1977) Biological control of Agriciltural

pests Proceedings of the International Congress of Entomology

15464-472

Sinha NP and Gulati KC(1963) Neem (Azadirachta indica) seed cake

as a source of pest control chemicals Bulletin of Regional Research

Laboratory Jammu India 176-177

Verma AN amp Khurana AD (1971) Incidence of armyworm Pseudaletia

separata Walker in different dwarf wheat varieties Haryana

Agricultural University Journal of Research 120-23

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

22

Gill JS and Lewis CT(197) Systematic action of an Insect feeding

detterent Nature (London) 2324Q2-403

Gopinadhan PB and Kushwaha KS(1978) Population trend of the armyworm

Mythimna separata Walker (Leoldoptera Noctuidae) under the Influence of

key ablotic and biotic factors In All India Workshop on Population

Ecology in relation to insects of gconomic Importance Jan 18-20 1978

Bangalore India

Goyal RS Gulati KC Sarup P Kidwal MA and Singh DS(1971)

Biological activity of various alcoholic extractives and isolates

of neem (Azadirachta Indica) seed cake against Rhopaios phum nympheae

(Linn) and Schistocorea gregaria Forsk Indian Journal of Entomology

32242-252

Grist DH and Lever RJAW(1969) Pests of Rice London UK

Longmans Green and Co Ltd 520 pp

Hsia TS Tsai SM and Ten HS(1963) Studies of the regularity of

oatbreak of the oriental armyworm Leucania sepgrata Walker II

Observations on the migratory activity of moths across the Chili gulf

an Yellow sea of China Acta Entomologica Sinica 12552-564

Hwang Guan-huel and How Wu-wel (1966) Studies on the flight of armyworm

moth (Leucanla separate Walker) I Flight duration and wing beat

frequency Acta Entomologica Slnica 1596-104

Jacobson M Reed OK Crystal MM Moreno DS and Soderstorm EL

(1978) Chemistry and biological activity of Insect feeding detterents

from certain weed and crop plants Entomologla Experimentalis et

Applicata 24448-457

Joshl BG and Sitaramalah S(1979) Neem Kernal as an ovipositional

repellent for Spodoptera litura (F) mothsPhytoparasltica 7199-202

23

Kalode MB Varma A Yadav CP amp Israel P(197) Feeding reaction

of armyworm (Cirphis compta Moore) larvae fed on some cultivated and

wild plants Indian Journal of Agricultural Sciences 41568-572

Koyama J(1966) The relation between the outbreak of armyworms (Leucania

separata Walker) and the richly nitrogeneous manured cultivation of

rice plants Journal of Applied Entomology and Zoology 10123-128

Koyama J(0970) Some considerations on the chronological records of

outbreaks of the armyworm (Leucania separata Walker) Japanese Journal

of Applied Entomology and Zoology 1457-63

Leuschner K(972) Effect of an unknown plant substance on a shield bug

Naturwissenchaften 59217-218

Li (Kuang-po) Wong Hun Chao (Shung-Jin) Chain (Shu-Ching) and Lin (Jung-You)

(1963) Field studies on the effect of microclimate on the populatdon

density of the armyworm Acta Phytophylacica Sinica 257-62

Li (Kuang-Po) Wong (Hong-hsiang) and Woo (Wen-sei)(1965) Route of the

seasonal migration of the oriental armyworm moth in the eastern part of

China as indicated by a three year result of releasing and recapturing

marked moths TCNo2 pp 101 to 110

Lin (Chang-Shan) (1963) Studies on the regularity of the outbreak of the oriental

armyworm (Leucania separata Walker) IV An analysis of the metereo-physlcal

conditions during the descending movement of the long distance migration of

the oriental armyworm moth Acta Phytophylacica Sinica 2111-122

Lin (Chang-Shan) and Chang (J Tsun-ping)(1964) Studies on the regularities of the

outbreak of the oriental armyworm (Leucania separata Walker)V A model for

seasonal long distance migration of the oriental armyworm Acta Phytophylacica

Sinica 393-100

Lin (Chang-Shan) Sun (Chin-ju) Chen (Rui Lo) and Chang (J Tsun-ping)(1963)

Studies on the regularity of the outbreak of the oriental armyworm

Leucania separata Walker I The early spring orientation of the oriental

armyworm moths and its relation to winds Acta Entomologica Sinica 12243-261

Ma SC(1979) Insect Ecology in the Peoples Republic of China Acta

Entomologica Sinica 22257-266

24

Mohyuddln AI amp Shah S(1977) Biological control of Mythlmna separata

(Lep Noctuldae) in New Zealand and its bearing on biological control

strategy Entomophaga 22331-333

Nagano M Yoshioka T Itayama T Nishino T Yamaguchi T and Nagata Y(1972)

Forecasting of the armyworm Leucaiia (Mythimna) separata Walker in grassland

I Outbreak in 1970 Proceedings of the Association for Plant Protection

Kyushu 1788-90

Neelgund YF and Mathad SB(1972) Nuclear polyhedrosis of Pseudaletia

separata (Lepidoptera Noctuidae) Annals of the Entomological Society

of America 65763-764

Oku T amp Kobayashi T(0974) Early summer outbreaks of the oriental

armyworm Mythimna separata Walker in the Tohoku District and possible

causative factors (LepidopteraNoctuidae) Applied Entomology and

Zoology 9238-246

Pradhan S Jotwani MG and Rai BK (1962) The neem seed detterent to

locusts Indian Farming 127-11

Pruthi jHS(1937) Report of the Imperial Entomologist In Scientific

report of Agricultural Research Institute New Delhi 1935-36

Puttarudriah M amp Usman S(1957) Flood causes armyworm outbreak Mysore

Agricultural Journal 32124-131

Schmutterer H and Rembold H(1980) Performance of some pure fractions

extracted from seed of Azadirachta indica on feeding activity and

metamorphasis of Epilachna varivestis (Co Coccinellidae) Zeitschrift

fur Angewandte Entomologie 89179-188

Sharma GK Ch Czoppelt and Rembold H(1980) Further evidence of insect

growth disruption by neem seed fractions Zeitschrift fur Angewandte

Entomologie 90439-444

Sharma HC and Davies JC(1982) The oriental armyworm Mythimna separata

Distribution biology and control - A literature review Tropical Pest

Management (submitted)

25

Simmonds FJ(1976) Some recent puzzles in biological control

Entomophaga 21327-332

Simmonds FJ amp Bonnett FD(1977) Biological control of Agriciltural

pests Proceedings of the International Congress of Entomology

15464-472

Sinha NP and Gulati KC(1963) Neem (Azadirachta indica) seed cake

as a source of pest control chemicals Bulletin of Regional Research

Laboratory Jammu India 176-177

Verma AN amp Khurana AD (1971) Incidence of armyworm Pseudaletia

separata Walker in different dwarf wheat varieties Haryana

Agricultural University Journal of Research 120-23

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

23

Kalode MB Varma A Yadav CP amp Israel P(197) Feeding reaction

of armyworm (Cirphis compta Moore) larvae fed on some cultivated and

wild plants Indian Journal of Agricultural Sciences 41568-572

Koyama J(1966) The relation between the outbreak of armyworms (Leucania

separata Walker) and the richly nitrogeneous manured cultivation of

rice plants Journal of Applied Entomology and Zoology 10123-128

Koyama J(0970) Some considerations on the chronological records of

outbreaks of the armyworm (Leucania separata Walker) Japanese Journal

of Applied Entomology and Zoology 1457-63

Leuschner K(972) Effect of an unknown plant substance on a shield bug

Naturwissenchaften 59217-218

Li (Kuang-po) Wong Hun Chao (Shung-Jin) Chain (Shu-Ching) and Lin (Jung-You)

(1963) Field studies on the effect of microclimate on the populatdon

density of the armyworm Acta Phytophylacica Sinica 257-62

Li (Kuang-Po) Wong (Hong-hsiang) and Woo (Wen-sei)(1965) Route of the

seasonal migration of the oriental armyworm moth in the eastern part of

China as indicated by a three year result of releasing and recapturing

marked moths TCNo2 pp 101 to 110

Lin (Chang-Shan) (1963) Studies on the regularity of the outbreak of the oriental

armyworm (Leucania separata Walker) IV An analysis of the metereo-physlcal

conditions during the descending movement of the long distance migration of

the oriental armyworm moth Acta Phytophylacica Sinica 2111-122

Lin (Chang-Shan) and Chang (J Tsun-ping)(1964) Studies on the regularities of the

outbreak of the oriental armyworm (Leucania separata Walker)V A model for

seasonal long distance migration of the oriental armyworm Acta Phytophylacica

Sinica 393-100

Lin (Chang-Shan) Sun (Chin-ju) Chen (Rui Lo) and Chang (J Tsun-ping)(1963)

Studies on the regularity of the outbreak of the oriental armyworm

Leucania separata Walker I The early spring orientation of the oriental

armyworm moths and its relation to winds Acta Entomologica Sinica 12243-261

Ma SC(1979) Insect Ecology in the Peoples Republic of China Acta

Entomologica Sinica 22257-266

24

Mohyuddln AI amp Shah S(1977) Biological control of Mythlmna separata

(Lep Noctuldae) in New Zealand and its bearing on biological control

strategy Entomophaga 22331-333

Nagano M Yoshioka T Itayama T Nishino T Yamaguchi T and Nagata Y(1972)

Forecasting of the armyworm Leucaiia (Mythimna) separata Walker in grassland

I Outbreak in 1970 Proceedings of the Association for Plant Protection

Kyushu 1788-90

Neelgund YF and Mathad SB(1972) Nuclear polyhedrosis of Pseudaletia

separata (Lepidoptera Noctuidae) Annals of the Entomological Society

of America 65763-764

Oku T amp Kobayashi T(0974) Early summer outbreaks of the oriental

armyworm Mythimna separata Walker in the Tohoku District and possible

causative factors (LepidopteraNoctuidae) Applied Entomology and

Zoology 9238-246

Pradhan S Jotwani MG and Rai BK (1962) The neem seed detterent to

locusts Indian Farming 127-11

Pruthi jHS(1937) Report of the Imperial Entomologist In Scientific

report of Agricultural Research Institute New Delhi 1935-36

Puttarudriah M amp Usman S(1957) Flood causes armyworm outbreak Mysore

Agricultural Journal 32124-131

Schmutterer H and Rembold H(1980) Performance of some pure fractions

extracted from seed of Azadirachta indica on feeding activity and

metamorphasis of Epilachna varivestis (Co Coccinellidae) Zeitschrift

fur Angewandte Entomologie 89179-188

Sharma GK Ch Czoppelt and Rembold H(1980) Further evidence of insect

growth disruption by neem seed fractions Zeitschrift fur Angewandte

Entomologie 90439-444

Sharma HC and Davies JC(1982) The oriental armyworm Mythimna separata

Distribution biology and control - A literature review Tropical Pest

Management (submitted)

25

Simmonds FJ(1976) Some recent puzzles in biological control

Entomophaga 21327-332

Simmonds FJ amp Bonnett FD(1977) Biological control of Agriciltural

pests Proceedings of the International Congress of Entomology

15464-472

Sinha NP and Gulati KC(1963) Neem (Azadirachta indica) seed cake

as a source of pest control chemicals Bulletin of Regional Research

Laboratory Jammu India 176-177

Verma AN amp Khurana AD (1971) Incidence of armyworm Pseudaletia

separata Walker in different dwarf wheat varieties Haryana

Agricultural University Journal of Research 120-23

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

24

Mohyuddln AI amp Shah S(1977) Biological control of Mythlmna separata

(Lep Noctuldae) in New Zealand and its bearing on biological control

strategy Entomophaga 22331-333

Nagano M Yoshioka T Itayama T Nishino T Yamaguchi T and Nagata Y(1972)

Forecasting of the armyworm Leucaiia (Mythimna) separata Walker in grassland

I Outbreak in 1970 Proceedings of the Association for Plant Protection

Kyushu 1788-90

Neelgund YF and Mathad SB(1972) Nuclear polyhedrosis of Pseudaletia

separata (Lepidoptera Noctuidae) Annals of the Entomological Society

of America 65763-764

Oku T amp Kobayashi T(0974) Early summer outbreaks of the oriental

armyworm Mythimna separata Walker in the Tohoku District and possible

causative factors (LepidopteraNoctuidae) Applied Entomology and

Zoology 9238-246

Pradhan S Jotwani MG and Rai BK (1962) The neem seed detterent to

locusts Indian Farming 127-11

Pruthi jHS(1937) Report of the Imperial Entomologist In Scientific

report of Agricultural Research Institute New Delhi 1935-36

Puttarudriah M amp Usman S(1957) Flood causes armyworm outbreak Mysore

Agricultural Journal 32124-131

Schmutterer H and Rembold H(1980) Performance of some pure fractions

extracted from seed of Azadirachta indica on feeding activity and

metamorphasis of Epilachna varivestis (Co Coccinellidae) Zeitschrift

fur Angewandte Entomologie 89179-188

Sharma GK Ch Czoppelt and Rembold H(1980) Further evidence of insect

growth disruption by neem seed fractions Zeitschrift fur Angewandte

Entomologie 90439-444

Sharma HC and Davies JC(1982) The oriental armyworm Mythimna separata

Distribution biology and control - A literature review Tropical Pest

Management (submitted)

25

Simmonds FJ(1976) Some recent puzzles in biological control

Entomophaga 21327-332

Simmonds FJ amp Bonnett FD(1977) Biological control of Agriciltural

pests Proceedings of the International Congress of Entomology

15464-472

Sinha NP and Gulati KC(1963) Neem (Azadirachta indica) seed cake

as a source of pest control chemicals Bulletin of Regional Research

Laboratory Jammu India 176-177

Verma AN amp Khurana AD (1971) Incidence of armyworm Pseudaletia

separata Walker in different dwarf wheat varieties Haryana

Agricultural University Journal of Research 120-23

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

25

Simmonds FJ(1976) Some recent puzzles in biological control

Entomophaga 21327-332

Simmonds FJ amp Bonnett FD(1977) Biological control of Agriciltural

pests Proceedings of the International Congress of Entomology

15464-472

Sinha NP and Gulati KC(1963) Neem (Azadirachta indica) seed cake

as a source of pest control chemicals Bulletin of Regional Research

Laboratory Jammu India 176-177

Verma AN amp Khurana AD (1971) Incidence of armyworm Pseudaletia

separata Walker in different dwarf wheat varieties Haryana

Agricultural University Journal of Research 120-23

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Table I

Incidence of plants damaged by Mythimna separata at ICRISAT Center (1977-1979)

plants damaged

Alfisols Vert isol s

Sorghum Pearl-Millet Sorghum Pearl-Millet

1977 1978 1979 1977 1978 1979 1977 1978 1979 1977 1978 1979

42 93 - - 01 - 02 05 -January 40 63 -

February - 130 - - - 33 - - () -

March - 16 - - (-) - - (-) - - (-) -

April - ) - - (-) - - (-) - - (-) -

May - () - - (-) - - (-) - - (-) -

June - -) - - (-) - - (-) - - 137 -

July - - 235 - 690 335 - - shy

-August 980 660 - 397 780 173 - - 185 - -

September 415 680 260 611 05 02 - 03 - - 354 shy

- - 234 - 03 - -October 430 03 - - 220

27 40 - - 413 - -November 387 03 -

December 31 86 - 30 20 - - 03 - shy

- Data not recorded

(-) Insect activity not observed

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Table2

Incidence of Mythimna separata larvae on sorghum in large scale intercropping trials (1975 to 80)

No of Mythimna larvaelO0 plants or earheads

SNo Year Activity Alfisols Vertisols REMARKS period

Sole crop Inter crop Sold crop Inter crop

1 1975 Oct - - 40 88 upto 7 larvaehead

2 1976 Sept - - 7 in heads

3 1977 Sept - 106 - 61 in vegetative phase

4 1978 Aug 9 13 25 15 in vegatative phase

5 1979 Sept 28 30 1 3 in heads

6 1980 Sept 12 14 9 11 in vegetative phase

- Not recorded

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

28

Table 3 Observations on the biology of M separata

October 1980 Jan-Feb 1981

StageParameter

Mean Range Mean Range

3 2-5Preoviposition period (days)

996 173-1439 shyEggsfemale

4 4-5 5Incubation period (days)

2-7 -Oviposition period (days) 5

1-15Longevity male (days) 6

-12 9-19 -Longevity female (days)

18-2119 18-23 19Larval period (days)

8-1210 10-11 10Pupal period (days)

29-3332-39 31Post-embryonic period (days) 33

(-) Not studied

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Table 4

Light trap catches of M separata at ICRISAT Center (Total of three traps) (1977 - 1979)

YearJ F i A M J J A S 0 N D Total Month

1977 0 0 2 0 0 0 3 780 4607 208 9 8 5617

1978 1 3 1 4 1 0 4 i0o4 1460 27 9 1 2515

1979 1 0 7 0 0 0 7 121 137 48 27 1 349

1 0 386a 1980 2 0 0 1 1 0 12 153 185 31

Total 4 3 10 5 2 0 26 2058 6389 314 46 10 8867

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Table 5 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

CIn different soil types)

Parasitization (Mortality due to factors other than parasites

Soil typeCrop

S-

tu r

o

4-)

L

a

-0 4) -c

E

n

-shy

4E

x )a)

C 0Cn

4 M0 4shy

1980

Farmers field SorghumAlfisol Un-sprayed Pearl Alfisols Millet Unsprayed SorghumVertisol s

113

40

350

841

875

614

796

875

509

116

125

112

44

25

243

09

00

49

00

00

00

141

100

188

Sprayed Alfisols SprayedVerti sol s

Pearl Millet Sorghum

623

389

711

478

658

430

116

112

103

270

98

44

00

00

138

255

1981

Farmers field Alfisols Unsprayed Alfisols UnsprayedVertisois

Sprayed Alfisols Sprayed

Sorghum

Sorghum P Millet Sorghum

Sorghum P Millet Sorghum

63

318 137 826

678 1084 1720

540

651 832 753

605 832 587

444

557 701

628

509 712 505

107

08 109

108 1 7 109 109 108

413

267 95

132

270 54

280

00

25 15

25

38 11

180

00

03 00

01 2 71

27 08 00

143

151 190

210

156 212 195

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Table 6 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

Parasitization (Mortality due to factors other than parasites

rQOJ S- U

Year Moth r 4 ( L

o-0 4 ot)

a oQ) x O

4)fl0

0 4

E

1979 Dec 236 407 305 116 483

1980 Jan 145 352 269 114 - - - 392

Jul 74 770 716 111 41 95 00 149

Aug 717 703 658 119 193 84 00 136

Sept 310 365 261 114 290 87 00 338

Oct 80 550 488 109 363 25 00 126

1981 Jun 25 920 800 115 00 01 00 200

Jul 985 868 711 109 04 11 05 270

Aug 2069 792 677 108 120 26 05 166

Sept 1264 467 3q6 109 410 53 11 125

Oct 978 454 392 107 362 14 00 229

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

TablE 7 PARASITIZATION OF MYTHIMNA SEPARATA LARVAE AT ICRISAT CENTER

(In different weeding treatments and cultivars)

Parasitization () Mortality due to factors other than parasites

SNo gt 4- o D S a

4- 04- C 43 Q

l ExBornu 240 604 404 1 3 50 138 267

2 G-73-K-77 240 600 454 04 29 146 260

3 BJ-104 240 696 454 04 42 104 233

4 NS-AX75 240 663 475 04 59 II13 277

5 Atrazir + 1 Handweeding 240 654 442 00 46 100 267

6 1 Hand weeding 240 608 458 04 25 179 238

7 Weed free 240 642 475 17 59 113 250

8 Weedy

check 240 659 413 03- 50 108 242

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

33

Table 8

Leaf area and dry weight consumption by 3rd instar larvae of

Mythimna separata (fad for 24 hours on different genotypes of pearl millet

Genotypes Leaf area consumed

100 sqcm Dry weight consumed

100 mg Damagerating

SAR-57 9899 6574 5

Souga-Local 4 3509 2473 183

PIB-228 7022 3782 25

NEP-310-5685 6835 5147 267

P-184 8078 5485 333

BJ-104 9427 5871 5

700112 675 0 3485 233

MBH-110 4438 2191 233

SAD-403I 8801 5333 467

P-27511 8809 5611 40

D-1051-I 5949 5417 217

P-3081 8223 5333 40

SEm 898 749 035

CD 2633 2196 104

1 lt10 leaf damage

2 10-20 leaf damage

3 25-40 leaf damage

4 40-60 leaf damage

5 gt60 leaf damage

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

34

TABLE 9

Effect of neem kernal (Azadirachta indica) powder and its alcoholic extracts on leaf feeding by Mythimna spearata (Free choice test)

No of larvae per pot atdifferent intervals Leaf

SNo Treatment Conc() Damage 24 hr 48 hr 72 hr 96 hr rating

1 Seed powder 1 20 15 11 7 50

2 Seed powder 2 10 6 6 4 36

3 Shell powder 1 14 11 4 3 36

4 Shell powder 2 8 7 3 4 42

5 Seed extract 05 9 7 5 3 24

6 Seed extract 10 5 4 2 2 22

7 Shell extract 05 10 5 3 3 26

8 10 10 8 4 3 28

9 Control 25 23 12 9 48

SEm 23 30 16 12 03

CD at 5 t 65 85 47 35 09

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

35

Table 10

EFFECT OF NEEM KERNALS AND ITS ALCOHOLIC EXTRACTS ON LEAF FEEDING BY M SEPARATA

(3rd instar larvae 20 larvae5 plants released-for 24 hours)

Leaf area Dry weightTreatment Conc consumed100 sqcm consumed100 mg

Shell powder (1) 4823 2825

Seed powder (1) 5493 2950

Shell extract (1) 3364 3700

Seed extract (1) 4707 2225

Control 9785 7075

57 100SEm

3001CD at 5 t 170

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Fig1 Light trap catches of Mythimna separata at ICRISAT Center (1974-1980)

551 1974

1975 so 1976

1977451 -- -- 1978

30541 17

20shy__j---

U 9

0

0a 7shy

a

5

4

3 -shy

2shy

16 10 14 1b 23 27 32 36 460q Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Standard weeks

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

(1974-1980)

Light trap catches of Mythimna separata at different locations

at ICRISAT Center

Fig2

40

Manmool (1975-80)

CI Building (1974-79)

Vertisol Watershed (1977-80) ----

30

0

0

3 4 4

4 2O

10 r

32 36~ 40-54

Nov 27 32p 36t

Dec 2310 14 19 Aug SeOcNoDc

1 6 May Jun Jul Feb Mar Apr

Jan Standard weeks

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

38

Flg3 Light trap catches of Mythilmna aeparata in rel - r4a t

Walker) at ICRISAT Center (1976-80)

perature and RH

so-

-

---

-

Moth catch

--- Max temp

in- temp

MaXRflMin RH

Mso 190

- rou wek moving amans

- We kly means

-

Rainfall (I

-

S0

rO1ct

1911

60

s

0

30 o

30 0 40 40 deg 20

0 20

10

1 |

0 -I40 520

350 1$

0-

0

so I

-0

6

+ ---

A2

aK

o

i-

9o

509

4002

10

0

40 20 0 b

1 20 10

10-I

r pr -6Y 0

-0 -

I-I LIi

AS

-shy

0r

O0 -

0

8 0

70_

3 I

4

0

30

30 ~--so

50- so 1977 40

40 shy 40 -- A

30- 30-

110- 2-0-

o ++

0-V97- +-20 1V

70 o+ 2

10 0 S6 J Feb

0~~~~~~-4--

10 l ]1

Mar Apr

I

May

lt

A

tand~rd w-k3

Jl Il I Sep Oc t Nov

_ e e

lIi+ -o 0-r-

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Fig4a Light trap catches and larval population of Mythimna separata at ICRISAT Center (1980)

O--O Trap catchnight - (weekly means)

LARVAL POPULATION

I Alfisols - unsprayed (Pearl millet)

20 ED Vertisols - unsprayed (Sorghum) F-40 Alfisols - sprayed (Pearl millet) shy

20 Vertisols - sprayed (Sorghum)

12 18 0-4J

4- 16QCax

x 0 4

o

2312

60

4-4shy

66

0

z 1A-4

2

Jun Jul Aug Sept Oct Nov

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Fig4b Light trap catches and larval population of Mythimna separata at ICRISAT Center (19b1)115 0--C Trap catch per night - (weekly means)

LARVAL POPULATION

[] Alfisols - unsprayed (Pearl millet)

EZ Vertisols - unsprayed (Sorghum)

1 0 shy10 Alfisols - sprayed (Pearl millet)

Vertisols - sprayed (Sorghum)

-10

1

r

a

Ei

00

0J

00

0

gt 0-0

-A - ---i I 0z

Jun Jul Aug Sept Oct Nov

Week intervals

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

____

Fig5a Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1980)

D No of larvae

] Pupation

650- Emergence

II Parasitization

[ Parasitizationby Hymenoptera

550shy4 Parasitization by Diptera O 500- 100 N

C0

450- 90

M07 to-) w -4

400 80

-4 350 EE-- 45 Ushy

0-3 X_ 702300- 7 60 7

0

wN

150- -

100- --20

50 1

f l

Farmers Field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

No of larvae reared (113) (40) (350) (623) (389)

Soil types

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Fig5b Population and extent of parasitization of the Mythimna separata larvae in different soil types at ICRISAT Center (1981)

400- C No of larvae

1 Pupation

VM Emergence

W m Parasitization

0 300

0--30 Parasitization by Hymenoptera

-[ Parasitology by Diptera

0 C o

0 -A-

U)U 4

2001

-44

z 6 100 410

- -

Farmers field Unsprayed Alfisols Unsprayed Vertisols Sprayed Alfisols Sprayed Vertisols Sorghum Pearl millet Sorghum Pearl millet Sorghum

Noof larve reared (63) (137) (826) (1084) (1720)

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Fig 6 Larval survival and parasitization of Mythimna separata on sorghum and pearl-millet

Sorghum

Pearl millet

Unsprayed Alfisols - Pearl millet Vertisols - Sorghum

1001 Sprayed Alfisols Unsprayped Alfisols 1980I 1981 1981

901

80shy

70 4

60

50

gt

20 II I

I I

10

10

r- C o U 0 rshy

-4 r- 0C 0- -4 C 0 U r - -

0 - 0 0 0

4j el -- ) ~ C 4 - H - -14- 41 4 44 a) 41cd 00 cc CUj4-j CUj ~ 4j +- 0 4J Q 4-~wU c c CU+l CUj c O C$ Cd 4-j CU

0 in ~~ P4~ N) NOp- M In 4 0N Q cis LU I rq 4C ) -H44 LI I )- aH

dl V) En E A w44C -4 -4 0 ~4JCU-94OP C13 cUd CUd-q -C c dIP =0CU CU ct -4CCU CU CU CU CU CU CU CU CU

dP d dP c d

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1

Fig7 Effect of extent of weeding in pearl-millet on larval populationand leaf damage of oriental armyworm

300-E ~ No of larvae5

CD at 5

Weedy check

260

Damage rating

LU SEm

n

200

180 Weed free

Cshy

1 and weeding

At razini

+ 1 Hand weeding

4

-3

o0 z

140

100

60shy

20--1

C

X

0--

N O NX -41

0 ~ N

0

C

r

~ O 4N-I0

gt -

r- C LI

-

gtH

C

X

N

N

0 N

__ _ 1