CHICKPEA DISEASES AND THEIR CHICKPEA DISEASES AND THEIR MANAGEMENTMANAGEMENT

 R.B. GAURR.B. GAUR

Head, Plant Protection Coordinated Unit, Agricultural Research Station, Rajasthan Agricultural University, Sriganganagar-

335001 (Rajasthan).

 

INTRODUCTIONChickpea is invaded by more than 50 pathogens reported from different parts of world (Nene et al., 1980). But only a few of them have the potential to devastate the crop. Some of the internationally serious diseases, in order of importance, are: Ascochyta blight, fusarium wilt, dry root rot, stunt, botrytis gray mold, black root rot, phytophthora root rot and pythium root and seed rot. 

(A) (A) FUNGAL DISEASES AFFECTING FUNGAL DISEASES AFFECTING AERIAL PLANT PARTSAERIAL PLANT PARTS

(1)(1) ASCOCHYTA BLIGHTASCOCHYTA BLIGHT:This disease was first observed in 1911 in the North-West Frontier Province of Pakistan (Butler,1911). Since than, the disease has been reported from 28 countries around the world including India. In Rajasthan state of India it was first reported by Gaur et al., 1983 when the disease caused an estimated loss of 51 per cent during three severe epidemics from 1980-81 to 1982-83 (Gaur and Singh,1993).

Symptoms:Symptoms:The disease usually builds up in February and March in Pakistan and northern India when the crop canopy is very dense and temperature are favourable for disease development. The disease usually appear around flowering and podding time as patches of blighted plants in the field. Dark brown lesions develop at the base of the stem and the seedling may collapse and die. Pycnidia may be formed on the lesions.

Pycnidia are observed on the blighted parts. Necrosis spreads killing the plants. On the leaves and pods the lesions are round with brown margins and a gray center t+hat contain pycnidia, often arranged in concentric circles. Heavily infected seeds are dark brown, shrinked and may loose about 77 per cent of its test weight and 52 percent of its total protein due to sever blight infection (Gaur and Singh, 1995).

Causal organism:Causal organism: Ascochyta rabiei (Pass.) Labr.The asexual or perfect stage of the fungus (A. rabiei) is characterized by the formation of fruiting bodies, which produces pycnospores. The sexual stage of the fungus (Mycosphaerella rabiei) is neither found on diseased chickpea debris nor cultured on media.

Perennation:Perennation: Crop debris and infected seeds are the principal sources of primary infection (Luthra and Bedi, 1932). The pathogen was found to survive in diseased debris for 8 months on soil surface at a temperature range of 10 - 41 oC and relative humidity of 48 – 80 per cent. Soil was not found to play any part in perennation of pathogen (Gaur and Singh 1998).

Epidemiology:Epidemiology: The disease builds up and spreads fast when night temperatrure are around 10 oC, day temperature around 20 oC, and rains are accompanied by cloudy days. Minimum rainfall of 50 mm with 11 precipitation days, atmospheric humidity above 85 per cent and average maximum temperature between 19-22 oC in January and February are important prerequisites for disease epidemic ( Singh and Gaur, 1988; Gaur and Singh, 1993). Excessive canopy development also favour blight development.

Management: Management: (i)(i) CulturalCultural: Burning of diseased crop stubbles after chickpea harvest followed by sowing of moong crop in Kharif and burning its stubbles before chickpea sowing reduces ascochyta infection in subsequent crop (Gaur and Singh, 1993, 1995). Deep planting (15 cm) to prevent infected seeds for emerging and avoiding the sowing (north east to south west) against wind direction (north south) is also recommended to check the spread of disease (Sattar, 1933; Gaur and Singh,1993). Inter cropping / mix cropping undcer cropping system, comprises the very effective means to check the spread of disease. Gaur and Singh, 1994,1996 suggested intercropping with wheat, barley and mustard to reduce disease spread. Late ssowing is recommended to minimize excessive vegetative growth.

(ii) Host resistanceHost resistance:Use of resistant varieties is considered one of the cheapest and effective mean of plant disease control. Many reports on the identification of resistance to ascochyta blight have appeared in the literature. The majority are from Indian subcontinent. At Sriganganagar more than 4 thousand chickpea lines have been tested in field under artificial epiphytotric condition. A comparative list of sources of resistance / tolerance against this disease is reproduced in Table-1.

Table. 1: List of chickpea lines reported resistant/ Table. 1: List of chickpea lines reported resistant/ tolerant to Ascochyta blight. tolerant to Ascochyta blight.

Chickpea lines showing resistant and moderately Chickpea lines showing resistant and moderately resistant reactionresistant reaction

F 8, C12/34, C235, G 543, H 75-35, GNG 146, GG –588, - 688, Gaurav (Desi Cultivar).

ILC-72,-200,-202,-2548,-3279,-3864

ICC-1069,-3932,-6373,-7514

ICCL-86447,FLIP-83-47C, MCK-54

ICCX-790151-2P-1H-1H-2H-1H-1HWR-BH, ICCX-800859-BPN_BPN-BPN-3BPN-1HWR-BH, ICCX-810457-3H-1H-1H-1HWR-BH

GL-83119, -84125

Cont…(Table-1)Cont…(Table-1)

Chickpea lines showing tolerant reactionChickpea lines showing tolerant reactionILC-182, -187, -195, -196, -2380, -2956, -3274, -3856, -3870

FLIP 82-1C, -82-191C, -83-46 C, -83-76 C

ICC- 6945

GNG- 84, - 146, -158, -166, -171, -173, -176, -184, -185, -187, -190, -366, -441, -469 (Samrat), -581, -638, -640, -644, -656, -663 (Vardhan), - 666, -678, -690, -698, -702

BG-257, -261

GG-575, -261

GL-1002, -1014, -84012, -86051

H 83-24, -83-55, -84-8, -86-21

Ref: Gaur et al. 1983, Gaur and Singh 1987,Gaur et al.1992, Gaur 1993, Gaur and Singh 1996 ; Reddy and Singh 1984, Singh et al.1984

(iii) (iii) Chemical:Chemical:(a) (a) Seed Treatment:Seed Treatment:Seed borne nature of Ascochyta rabiei makes fungicidal seed treatment essential and useful. Seed borne inoculum can be eradicated by treating seeds with following chemicals. 2-hr immersion in malachite green @ 5mg/ lit water. 4-hr immersion in formalin. 12-hr immersion in pimaricin @ 150 mg/ lit water.

Seed treatment with Phenthiuram @ 2gm/ kg seed or Thiram @2gm/ kg seed or Benomyl @ 2gm/ kg seed or Calaxin M @ 3gm/ kg seed or Calaxin M + Bavistin (1:1) @ 2 gm/ kg seed or Bavistin + Thiram @ 3 gm/ kg seed. ( Ref: ICRISAT Information Bulletin No. 28) Studies conducted by Gaur (2003) showed significant reduction in seed borne infection and marked increase in germination when seeds were immersed in 0.2 per cent Thiobendazole solution for 4-hrs. Calixin M and hot water treatment, though markedly checked the seed borne infection, adversely affected germination.

(b)Foliar application:Foliar application:Several reports on the use of chemicals for foliar spraying have appeared in literature. Bordeaux mixture, wettable sulphur, Zineb, Ferbam, Maneb, Captan, and Chlorothalonil have been reported to reduce disease infection significantly. (Ref: ICRISAT Information Bulletin No. 28). Foliar sprays are generally ineffective under epidemic condition. Even under moderate disease situation, four to six sprays become necessary to significantly reduce the disease. Gaur and Singh (1985) reported significant control of disease by four sprays of Chlorothalonil (@ 0.1%) or Dithianon (@ 0.1%) or Capatofol (@ 0.2%) at 10 days interval.

REFERENCESREFERENCES::      Butler, E.J. 1911. Fungi and diseases in plants. Bishen Singh Mahender Pal Singh, New Connaught Place, Dehradun Periodical Experts, 42-D, Vivak Vihar, Delhi 32, 547 pp. Nene, Y.L. 1980. Diseases of chickpea.Proceeding, International Workshop on chickpea Improvement. ICRISAT, 28 Feb.- 2 Mar. 1979, Hyderabad, A.P., India, pp,171-178. Gaur, R.B., T.B.Bhanushally, R.V.Maheshwari, R.D.Singh and R.P.Bhardawaj (1983). The screening of chickpea cultivars for resistance to Ascochyta blight under natural and artificial condition. International Chickpea Newsletter. 9 : 21. Gaur, R.B. and R.D.Singh (1985). Control of Ascochyta blight of chickpea through foliar spray. International Chickpea Newsletter. 13 : 22-24. Gaur, R.B. and R.D.Singh (1987). Evaluation of chickpea cultivars for resistance to Ascochyta blight under artificial condition I. International Chickpea Newsletter. 16 : 3.

Gaur, R.B., R.V Maheshwari and R.S.Verma (1992). Evaluation of chickpea cultivars for resistance to Aschochyta blight under artificial conditions II: Screening of breeding material. International Chickpea Newsletter. 26 : 23-24. Gaur, R.B. ( 1993). Evaluations of chickpea lines for resistance to Ascochyta blight.International Chickpea Newsletter. 28 : 15. Gaur, R.B. and R.D.Singh (1993). Epidemiology of Chickpea Ascochyta blight. Indian Journal of Mycology and PlantPathoogyl. 23 (2) : 135-140. Gaur, R.B. and R.D.Singh (1993). Loss estimation due to Ascochyta blight epidemics in Chickpea under different agro climatic situations of Sri Ganganagar. Indian Journal of Pulses Research: 6 (2) : 173-177. Gaur, R.B. and R.D.Singh (1994). Cropping system in relation to Chickpea blight (Ascochyta rabiei) I: Effect of intercropping on Ascochyta blight spread. Indian Journal of Mycology and. Plant Pathology. 24 (1) : 33-37.

Gaur, R.B. and R.D.Singh (1995). Effect of some cultural practices on perennation of Ascochyta fungus of Chickpea. Advances in .Agricultural Research in India. IV: 36-46. Gaur, R.B. and R.D.Singh (1996). Cropping system in relation to Chickpea blight (Ascochyta rabiei). II. Effect of multi row intercropping on Ascochyta blight spread. Indian Journal of Mycology and Plant Pathology. 26 (1) : 14-18. Gaur, R.B. and R.D.Singh (1996). Evaluation of Chickpea cultivars for resistance to Ascochyta blight. Indian Journal of Mycology and Plant Pathology. 26 (1) : 50-55. Gaur, R.B. and R.D.Singh (1996). Influence of storage period and temperature on viability of internally and externally seed born Ascochyta rabiei. Indian Journal of Mycology and Plant Pathology. 26 (2) : 213-216. Gaur, R.B. and R.D.Singh (1996). Effect of Ascochyta blight on grain yield and protein in chickpea. Indian Journal of Mycology and Plant Pathology. 26 (3): 259-262.

Gaur, R.B. and R.D.Singh (1998). Survival of Ascochyta rabiei and transmission of Chickpea blight through plant debris and soil. World Weeds. 45 (3-4) : 249-256.

Gaur, R.B. and R.D.Singh (2001). Host nutrition in relation to chickpea blight (Ascochyta rabiei) Development. Journal of Mycology and Plant Pathology. 31 (2) : 207-210.

Gaur, R.B., R.R.Sharma and S.K. Yadav. 2002. Traditional wisdom in the farming communities of semi-arid region of Rajasthan. Agricultural Heritage of India(eds.Y.L.Nene and S.L.Choudhary). AAHF.,Secunderabad India : pp 91-96.

Gaur, R.B. 2003. Eradication of seed boarne inoculum of Ascochyta rabiei (Pass.) Lab. by fungicidal and thermal treatment of chickpea seeds. Indian Journal of Plant Protection. 31 (1) : 68-72.  

(2) (2) BOTRYTIS GREY MOLDBOTRYTIS GREY MOLDBotrytis gray mold of chickpea has been reported from Argantina, Australia, Bangladesh, Canada, Columbia, India, Nepal, Pakistan, Spain, USA, (Nene et al. 1984). The first record of the occurrence of grey mold of chickpea in India was by Shaw and Ajrekar (1915). However, the first record of epidemic in chickpea crop in Uttar Pradesh in India was reported by Joshi and Singh (1969). The disease appeared in an epiphytotic form during 1979 and destroyed chickpea crop over an area of 20,000 hectares in ‘Tal’ area of Bihar (India). In 1980-81 the disease caused 70-100 % losses at the control state farm, Hisar and parts of Punjab (Grewal and Laha, 1983).

Symptoms :Symptoms : Symptoms appear on stem, leaves, flowers and pods as grey or dark brown lesions covered with mouldy fungal growth. Tender branches break-off at the point where grey mold cuase rotting. Affected leaves and flowers turn into rotting mass. On thick branches lesions are large (10-30 mm) and stem break at the point where soft rot has occurred.

Under conditions of favourable weather persisting for several days, the blightling of foliage spread rapidly and the entire plant dries up. Only small, shriveled seeds are formed in affected pods. Grayish white mycelium may be seen on immature seeds. Lesions on pods are water-soaked and irregular, with some times black sclerotial bodies scattered in the infected areas.

Causal organism:Causal organism:Botrytis cinerea Pers. ex Fr.The perfect stage is Sclerotinia fuckeliana. However there is no report of the occurrence of the perfect stage on chickpea.

Epidemiology :Epidemiology : The fungus has a wide host range and the inoculum is almost always present in the environment waiting for the right weather to become active. Contaminated seeds can introduce diseases in to new regions or re contaminate areas with new strains where the disease was already existing. Many reports suggest that the pathogen remains viable in seeds up to next growing season.

Management: Management: (I)(I) Cultural:Cultural: Adopt wider spacing in disease prone area or thin out an infected crop to allow more light to penetrate the canopy. Inter cropping with linseed is recommended which is resistant to the pathogen.. Avoid excessive vegetative growth. Avoid excessive irrigation. Late sowing is recommended to minimize excessive vegetative growth.Use varieties with an erect and open growth habit.

(ii) (ii) Host resistanceHost resistance::Large number of chickpea varieties/ lines/ crosses have been identified as resistant by different workers. But under multilocational testing only few showed resistance. Few among these are: ICC-1069, ICC-5035, ICC- 10302 and GG- 588.

(iii) (iii) ChemicalChemical::(a)(a)Seed TreatmentSeed Treatment:Seed borne inoculum can be eradicated through dry seed dressing with following chemicals: Vinclozolin (Ronilan), MBC plus Thiram combination or MBC alone (Grewal and Laha, 1983). Bavistin, Bavistin + Thiram (1:1), Ronilan and Benlate (Rewal 1987). Bavistin + Thiram in the ratio of 1:4 ( Pandey, 1988).

(b) Foliar applicationFoliar application:Foliar spray of various fungicides to protect the crop from aerial infection have also been reported by various workers. Seed treatment with Bavistin + Thiram (1:4) followed by 3 sprays of Bavistin at 10 days intervals gave excellent control of disease (Pandey, 1988). Grewal and Laha (1983) and Rewal (1987) reported Foliar sprays of Ronilan, Bavistin, or Bavistin + Thiram to protect the crop from aerial infection.

REFERENCES:REFERENCES: Shaw, F.J.F., and Ajrekar, S.L. (1915). “The Genus Rhizoctonia in India.” Mem. Dept. Agric. India. Bot. Ser. 7: 117. Joshi, M.M., and Singh, R.S. (1969). “A Botrytis Grey Mould of Gram.” Indian Phytopathol. 22: 125. Grewal, J.S., and Laha, S.K. (1983). “Chemical Control of Botrytis Blight of Chickpea.” Indian Phytopathol. 36: 516. Pandey, B.K. (1988). “Studies on Botrytis Grey Mold of Chickpea (Cicer arietinum L.).” Ph.D. thesis, Plant Pathology, G.B.P.U.A. & T., Pantnagar, 173. Rewal, N. (1987). “Studies on Variability in Botrytis cinerea Pers. Causing Grey Mould of Chickpea and Its Management.” (Ph.D. thesis, I.A.R.I., New Delhi. 104.

(3) (3) ALTERNARIA BLIGHTALTERNARIA BLIGHT::Alternaria blight caused by Alternaria alternata has been reported from Bangladesh and India, and possibly Nepal (Nene et al., 1984). From Rajasthan in India it was first reported by Gaur and Singh (1990). The disease is of minor importance unless congenial condition prevails for long.

Symptoms:Symptoms: The disease occurs mostly in the adult stage of the chickpea plant. All the aerial parts are affected (Haware and Nene 1980). Infection is generally severe on leaves . Lesions on leaflets are water-soaked initially, restricted in size, circular, and purple in colour. These are surrounded by chlorotic tissues but without definite margins. Lesions later turn brown to dark brown. With high humidity, they coalesce, cover the leaf area, and cause rapid withering of the individual leaflets.

Sporulation can be observed on necrotic tissues under the stereobinocular microscope. On the stems the lesions are elongated and brown to black. On the pods they are circular, slightly sunken and scattered irregularly. Pods become dirtly black. On mature pods, tiny, black superficial flecks remain localized Seed is infected and shriveled.. Under favorable weather conditions, entire foliage is killed.

Causal organism:Causal organism:

Alternaria alternata (Fr.) KiesslerThe perfect state of A. alternata is Pleospora infectoria and this was also found to cause chickpea blight (Haware and Nene 1976).

Epidemiology Epidemiology ::It is a seed and soil borne disease. Weather conditions ( temperature and humidity) that favour the development of this disease are similar to those for ascochyta blight and botrytis gray mold and all three diseases can occur together.

Management: Management: (i) (i) Cultural:

Adopt wider spacing in disease prone areaa or thin out an infected crop to allow more light to penetrate the canopy. Avoid excessive vegetative growth. Avoid excessive irrigation. Rotate the crop.

(ii) (ii) Host resistanceHost resistance::Large number of chickpea varieties/ lines/crosses have been identified as resistant by different workers. But under multilocational testing only few showed resistance. Few among these are: ICC-1069, ICC-5035, ICC- 10302 and GG- 588.

(iii) (iii) ChemicalChemical::(a) (a) Seed TreatmentSeed Treatment:: Seed borne inoculum can be eradicated through dry seed dressing with Bavistin @ 2 gm/kg seed.(b)(b) Foliar applicationFoliar application:Foliar spray of Mancozeb (@ 0.2%) or Carbendazim (0.2%) is recommended to protect the crop from aerial infection.

REFERENCES:REFERENCES: Gaur, R.B. and R.D.Singh (1990). A new report of

Alternaria blight of chickpea from Rajasthan India. Indian J. Mycol. Pl.Pathol. 20 (1) : 77-78. Nene , Y.l., Sheila , V.K., and Sharma, S.B. 1989. A world list of chickpea (Cicer arietinum L.) and piggeonpea (Cajanus cajan (L.) Millsp.) pathogens. Legumes Pathology Progress Report-7, Patancheru, A.P. 502 324, India: International Crops Research Institute for the Semi-Arid Tropics. 23 pp. 

Table-2. SOME OTHER FUNGAL DISEASES Table-2. SOME OTHER FUNGAL DISEASES AFFECTING AERIAL PARTRS.AFFECTING AERIAL PARTRS.Following diseases have also been reported affecting aerial Following diseases have also been reported affecting aerial parts of the chickpea crop. but these are of minor importance parts of the chickpea crop. but these are of minor importance only:only:

Disease Causal organism First Report

Colletotrichum blight

Colletotrichum dematium (Pers. ex Fr.) Grove

Mishra et al., 1975 from central India

Phoma blight (Phoma medicaginis Malbr. & Roum)

 

Haware and Nene, 1981 from Jammu and Kashmir

Stemphylium blight (Stemphylium sarciniforme (Cav.) Wilts.

Das and Sen Gupta, 1961 from West Bengal

Cont…..(Table-2)

Rust

 

Uromyces ciceris-arietini (Grogn.) Jacz. & Beyer

Payak 1962 from Shimla hills

Powdery mildew

 

Oidiopsis taurica (Lev.) Salmon

Nour 1957 from sudan

Sclerotinia stem rot

Sclerotinia sclerotiorum([Lib.) de

Bary

Nene et al.1984 from many countries

Scopulariopsis leaf spot

Scopulariopsis brevicaulis

Gaur et al., 1988 Rajasthan, India

REFERENCES:REFERENCES: Das , G.N. and Sen Gupta. 1961. A stemphylium disease of gram. Plant Disease Reporter. 45: 979. Gaur, R.B., R.S.Rathore and R.D.Singh (1988). A new leaf spot disease of chickpea incited by Scopulariopsis brevicaulis. Current Science. 57 (15) : 855-856. Haware, M.P. aand Nene, Y.L. 1981. Phoma blight. A new disease of chickpea. Plant Disease. 65: 282. Payak, M.M. 1962. Natural occurrence of gram rust in uredial stage of Trigonella polycerate L. in Shimla hills. Current Science. 31: 433-434. Nene, Y.L., Sheilla, V.K., and Sharma, S.B., (1984). “A World List of Chickpea (Cicer arietinum L.) and Pigeonpea (Cajanus cajan(L.) Millsp.) Pathogens.” ICRISAT Pulse Pathology Progress Report No. 8: 19. Nour, M.A. 1957. Control of powdery mil;dew diseases in the Sudan with special reference to broadbean. Imperial Journal of Expermental Agriculture. 25:119-131. 

(B) FUNGAL DISEASES AFFECTING (B) FUNGAL DISEASES AFFECTING ROOT/ STEM BASEROOT/ STEM BASE 

(1) CHICKPEA WILT:Fusarium wilt is serious disease of chickpea. The disease has been reported from several countries including India (Nene et al. 1984). All types of chickpea irrespective of plant type and seed size succumb to the disease. In general spring sown crop is more vulnerable to wilt than winter sown The seeds harvested from wilted plants are lighter, wrinkled, and duller than those from healthy plants . The yield losses vary between 10 percent and 100 percent depending on the agroclimatic conditions (Grewal and Pal, 1970).

SymptomsSymptoms : :Generally the disease occurs at two stages of plant growth: (i) Seedling stage and (ii) flowering stage or adult stage.

(i) Seedling stage:

The disease can be observed about 3 weeks after sowing. The seedlings (3 to 5 weeks after sowing) collapse and lie flat on the soil surface, although they retain normal green colour. Such diseased seedlings, when uprooted generally show uneven shrinking of the stem above and below the collar region.

The affected seedlings do not show any internal root rot; however, when split open vertically from collar region downward, black discolouration of xylem vessel is visible. The seedlings of highly susceptible cultivars which die within 10 days after emergence may not exhibit black discoloration of internal tissues. However; the internal browning from root rip upward would be observable.

(ii) Adult stage:In the case when adult plants (6-8 weeks after sowing) are infected the disease plants exhibit drooping of petioles, rachis, and leaflets. Initially, drooping is observed in the upper part of the plants, but with in short time (1-2 days) it is visible on the entire plant. The lower leaves dry but are not shed at maturity.

External root rot is not observed but the central inner portion shows dark brown to black discoloration of xylem below and above collar region. Sometimes only a few branches are affected which result in partial wilting. In the initial stage of wilting, the discolouration may not be continuous. Discolouration also extends several centimeters above the collar region into the main stem and branches. If a transverse cut is given with a sharp razor blade through the collar region, black discolouration of pith and xylem can be seen.

Causal organism:Causal organism:Fusarium oxysporum Schlecht. emend Snyd. & Hans. f.sp. ciceri (Padwick) Snyd. & Hans.  

EPIDEMIOLOGY : The fungus may be seed borne present in the hilum of the seed in the form of chlamydospore like structure and may survive in plant debris in soil. The fungus may survive in soil for more than five years. The primary infection is through chlamydosporus or myclia. The conidia of the fungus are short lived; however, the chlamydosporus can remain viable up to next crop season. The fungus however, did not survive in the roots placed on the soil surface. Plant species other than chickpea (pigeanpea, lentil, pea) may serve as symptomless carrier of the disease.

The pathogen may also parasitize several weeds such as Cyprus rotendus, Tribulus terestris, Convolvulus arvensis and cardiospermum halicacabum. The soil type, reaction, moisture and temperature are known to influence diseases development (Singh et al. 1985) The disease is more severe in light sandy soils than heavy clay ones. Alkaline soils in general favour incidence of wilt. Soil temperature relations showed that the disease is otimum at 250C and is at a lower ebb at 200C. The amount of organic matter and humus content of the soil were found inversely related to will incidence.

(2) DRY ROOT ROTDRY ROOT ROT:The first report of dry roor rot was probably from India by Mitra (1931). It is one of the major disease of chickpea in Rajasthan. The disease generally appears around flowering and podding time in the form of scattered dried plants.

Symptoms:Symptoms: Drying of the whole plant is the only conspicuous symptoms of this disease. Affected plants are seen scattered in the field. The petioles and leaf lets droop only at the very top of the plant. The leaves and stems of the affected plants are usually straw coloured, but in some cases the lowere leaves and stems will show brown colour. The lower portion of the tap root usually remains in the soil when plants are pulled. The tap rootis dark, show sign of rotting and is devoid of most of the lateral and finer roots. Some time near the tap root tip a grayish mycelial coating can be seen.

The dead root is quite brittle and shows shredding of bark. The root tip can be easily broken. Very minute sclerotial bodies can be seen with the aid of 10 X hand lens on the exposed wood of the root, as well as on the inner side of the bark. When the dry stem of the collar region is split open vertically, either sparse thread like mycelium or minute sclerotia can be seen (with hand lens) in the pith.

Causal organism:Causal organism:Rhizoctonia bataticola Taub) Butler; Macrophomina phaseolina (Maub) Ashby Maximum ambient temperature above 30 oC, minimum above 20 oC, and moisture stress favour disease development.  

(3) WET ROOT ROTWET ROOT ROT:It is a minor disease and is reported from several countries.Symptoms:This disease is seen most often in the seedling stage (up to 6 weeks after sowing) in soils with relatively higher moisture content .Affected seedlings gradually turn yellow and petioles and leaflets droop. Generally seedling do not collapse. A distinct dark brown lesion appears above the collar region on the main stem and can extend to lower branches in older plants. The stem and rot below the lesion show rotting frequently with pinkish mycelial growth. Sclerotia are not seen.

Causal organism:Causal organism:Rhizoctonoa solani Kuhn 

(4) (4) BLACK ROOT ROTBLACK ROOT ROT::It is a minor disease reported from many countries including India.Symptoms: The disease can occur at any stage. Affected plants turn yellow and wilt. Dead plants are seen scattered in the field. The root system is rotten. Most of the finer roots are shed and the remaining roots turn black. Affected plants dry prematurely but may go on producing new roots if sufficient moisture is available.

Causal organism:Causal organism:

Fusarium solani (Mart.) Sacc. Excessive moisture and moderately high temperature (25 – 30 oC ) encourage disease development . 

(5)(5) COLLAR ROT COLLAR ROT::It is widely prevalent disease and can cause considerably loss to plant stand when soil moisture is high and temperature are warmer (30 oC) at sowing time.

Symptoms:Symptoms: Disease is seen at seedling stage (up to 6 weeks after sowing) particularly if the soil is wet. Affected seedling turn yellow. Young seedling may collapse but older seedling may dry with out collapsing. Leaves do not drop.

When uprooted, the seedling show rotting at the collar regionand down wards.The rotted portion is covered with whitish mycelial strands. Rape seed like sclerotia attached to mycelial strands around the collar can be seen.

Causal organism: Causal organism: Sclerotium rolfsii Sacc.The disease is favoured by the presence of undecomposed organic matter on the soil surface and excessive moisture at the time of sowing and at seed ling stage. Disease incidence is higher when chickpea is sown after rice.

(6) (6) STEM ROTSTEM ROT::It is reported from most of the chickpea growing regions of the world. It can affect the criop at any stage.

Symptoms:Symptoms: The disease occur mostly on adult plants when these form a thick canopy and when the soil remain wet for an extended period.

The above ground symptoms are drooping of petioles and leaflets with out turning yellow. Ultimately the leaves dry and turn straw coloured prematurely. A web of white mycelial strands appear in the collar region and above and may cover the base of branch. Whitish irregular sclerotial knots can be seen occasionally mingled with mycelial strands on branches. The below ground plant parts show surface discolouration, but no internal discolouration.

Management of fungal diseases affecting Management of fungal diseases affecting root/ stem base:root/ stem base:

(i) (i) Cultural:(a) WiltWilt: Use disease free seed. Avoid sowing when temperatures are high. Follow 6-year crop rotation. Planting should be delayed. Planting of seeds at proper depth (10-12 cm) is helpful in reducing disease incidence.

Development of wilt is more prominent under moisture stress conditions. One irrigation before flowering decreases disease incidence and increases yield. Mixed cropping of chickpea with wheat and berseem have given measurable disease control.

(b)Dry root rotDry root rot: Avoid drought. Sow in time so that crop escape hot weather.

(c) Wet root rot: Avoid excessive rich soil. Avoid high soil moisture at sowing.

(d) Black root rotBlack root rot: Avoid high soil moisture.

(e) (e) Stem rotStem rot:: Avoid excessive vegetative growth. Avoid excessive irrigation.(f) Collar rot: Avoid high soil moisture at sowing and seedling stage. Remove all undecomposed organic matter while preparing seed bed.

(ii) (ii) Host resistanceHost resistance::On the basis of multi location testing for fusarium wilt and root diseases several stable and durable sources of resistance have been identified by Nene (1988) and other chickpea workers.

Table-3. Varietal resistance in chickpea against wiltTable-3. Varietal resistance in chickpea against wilt..

Cultivars/Lines Reported By

G-24

11 lines

ICCC-10, DA-1

(multiple disease nesostart)

14 lines, C. jeedaicum

P.597, P.621, P.3649, P.4115, P.4128, P.4245, P.4347

PL-Se-Be 81 series, nos. 48, 78, 86, 87, 103, 116, 146

(Symptom free, but infected)

ICC-11313, ICC-12237, ICC-12239, ICC-12258, ICC-12259, ICC-12275

GG-588, GG-609

Singh & Sandhu, 1974

Singh et al., 1974

Jalali et al., 1980

Nane & Haware, 1980

Govil and Rana, 1984

Halila et al., 1984

Patel et al., 1985

Singh et al., 1986

Table-4. Chickpea entries with multiple disease Table-4. Chickpea entries with multiple disease resistance. resistance.

Cultivars/Lines Resistance To

ICP-12237, ICP-12269

ICC-1069

ICC-10466

ICC-858, ICC-4918, ICC-8933, ICC-9001

Fusarium wilt, dry root rot, black root rot 

Fusarium wilt, Ascochyta blight, Botrytin grey mold.

 Fusarium wilt, dry root rot, stunt

 

Fusarium wilt, Sclerotinia stem rot

 

(iii) (iii) ChemicalChemical::(a) (a) Seed treatmentSeed treatment:: Seed treatment with 0.15 percent Banlate T (30% banomyl + 30% thiran) destroys the seed borne fungus completely. (Haware et al., 1978). Seed treatment with Bavistin or carboxin (0.25%) protected the plants in plotted soil infested with pathogen (Verma, 1976). Seed inoculatum with Rhizobium followed by seed treatment with Bavistin (0.1%) is more effective in reducing wilt, incrosing nodule/plant and yield than Bavistin (0.1%) alone (Anonymous, 1983).

Seed improvement with Bavistin + thiram ( 0.5 + 2.0 g/kg seed) has also been found promising (Jalali et al., 1980-81). Seed treatment with garlic leaf extract and neem oil are also reported to produce disease free seedlings (Singh et al., 1979; 1980).

(b) Soil application of Phosphorus and (b) Soil application of Phosphorus and Zinc:Zinc: Gaur and Vaidya, 1983 reported significant reduction in root rot (F. solani) incidence with soil application of 40 kg P2 O5 combined with 3 kg /ha of ZnSo4.

(iv) Biological congtrolBiological congtrol: Jalali and Thareja (1981) observed suppression of the disease in plotted plants following soil inoculation with vesicular-arbuseular mycorrhizal fungus. Trichoderma harzianum multiplied on faecal pellets of goat and sheep, gram shells and farm yard manure was found to control dry root rot disease significantly ( Gaur et al., 2005 ). Gaur et al., 2005 observed significant control of dry root rot by treating the seeds with talc based formulation of Trichoderma harzianum @ 10 gm/ kg seed followed by soil application of Trichoderma harzianum @ 10 kg/ ha multiplied in 200 kg of FYM.

REFERENCES:REFERENCES: Gaur, R.B. and P.K.Vaidya (1983). Reduction of root rot of chickpea by soil application of phosphorus and zinc. International Chickpea Newsletter. 9 : 17-18. Gaur, R.B.,R.N. Sharma,R.R. Sharma and Vinod Singh Gautam.2005. Efficacyof Trichoderma for Rhizoctonia root rot control in chickpea. Journal of Mycology and Plant Pathology. 35 (1): 144-150. Gaur, R.B., R.N. Sharma and R.R Sharma. 2005. Shelf- life of talc based formulation of Trichoderma and soil application for biological control of dry root rot of chickpea. Journal of Mycology and Plant Pathology. 35 (2) : 380-384. Grewal, J.S., and Pal, M., (1970). “Fungal Diseases of Gram and Arhar.” Proc. IV Annual Workshop on Pulse Crops, P.A.U., Ludhiana, 168. Nene, Y.L., Sheilla, V.K., and Sharma, S.B., (1984). “A World List of Chickpea (Cicer arietinum L.) and Pigeonpea (Cajanus cajan(L.) Millsp.) Pathogens.” ICRISAT Pulse Pathology Progress Report No. 8: 19. Singh, R.D., A.K.Bhargava and R.B.Gaur (1985). Some observation on the incidence of chickpea wilt in Sriganganagar district, Rajasthan (India). International Chickpea Newsletter. 13 : 15-16.

Viral Diseases 

(1) STUNTSTUNT: 

Nene and reddy (1976) described this disease.

Symptoms:Symptoms: Affected plants can easily be spotted in the field by their yellow,orange, brown discolouration with stunted growth. Stunting is due to shortened internodes. The leaflets are smaller in size and show yellow orange or brown discolouration. The stem and leaves of diseased plants are stiffer and thicker than normal.

A shallow vertical knife cut at the colar region invariably yields phloem browning which is the most characteristic symptom of stunt. If plants survive up to podding stage, very few pods can be seen.

Causal Organism:Causal Organism: 

Pea leaf roll virus. There are recent indication that more than one virus is involved in different part of India. Transmitted by aphid viz. Aphis craccivora and Myzus persicae.

Control:Control: Early sowing and wider spacing favour stunt incidence. Adopt close spacing and sow when aphid activity is low.It could be early or late sowing depending on location. Control leaf hopper and aphids.

Table-5. Minor viral diseases.Table-5. Minor viral diseases. 

Disease Symptoms Cause

Mosaic Chlorosis of the terminal bud and twisting followed by necrosis and proliferation of secondary branches

Alfalfa mosaic virus

Narrow leaf Yelowing and drying of the plants with feathery and deformed leaves. Initiation of very narrow leaves from new buds.

Bean yellow mosaic virus

Cont…(Table-5)Necrosis Present in Australia

only. Terminal of the main and axillaryshoots are twisted.

Lettuce necrotic yellow virus

Phyllody Excessivr proliferation of branches with smaller leaflets givinf a bushy appearance. Flowers are converted in to leafy structure.

Mycoplasma

Ascochyta infected chickpea plant parts

Identifying Ascochyta resistance in chickpea by the technique developed at the centre

Curtsey-ICRISAT

Curtsey-ICRISAT

Curtsey-ICRISAT

Curtsey-ICRIST

Curtsey-ICRISAT