Rice lecture final

Production Technology of Riceby

Hafiz Ali Bashir

Origin, History and Importance Rice is cultivated and eaten mostly in the “rice bowl” region,

which consists of Asia and middle/near east countries. Juliano 1985:15

IRC 2003:154888

Rice has been cultivated in these regions for over nine thousand years, which means that it is highly variable and adaptable. Its been grown in the lowlands of India to as high as three thousand meters in Nepal. Lang 1996:5

IRC 2003:18437

Native to the deltas of the great Asian rivers

the Chang (Yangtze), Tigris, Euphrates. Ganges,

First domesticated in, Eastern Himalayas (i.e. north-eastern India), Burma, Thailand, Laos, Vietnam and Southern China. southern China

In the sub-continent found in the north and west in 2000 BC.

Perennial wild rice still grow in Assam and

Nepal.

In southern India it appeared 1400 BC after its domestication in the northern plains.

Consumed by 5.6 billion people world wide.

World consumption is highest in Asian countries.

Rice industry is an important source of employment and income for rural people.

Provides 21% per capita energy.

15% of per capita protein. Seventy percent of daily calories.

Provides minerals, vitamins, fiber, vitamin A, zinc and iron.

Rice exporting countriesSr. No Countries Export

1 Thailand 10 million tons (34.5% of global rice exports)

2 India 4.8 million tons (16.5%)

3 Vietnam 4.1 million tons (14.1%)

4 Myanmar 3.314 million tons (11.0%)

5 United States 3.1 million tons (10.6%)

6 China 901,550 tons (3.1%)

7 Egypt 836,940 tons (2.9%)

8 Italy 668,940 tons (2.3%)

Rice cultivation in PakistanPakistan’s annual production is more than 4.57

million tons and area 2.21 m.ha.

Kollar track of rice consists of Gujranwala, Lahore, Sialkot, Shakhupura, Hafizabad.

Third largest crop after wheat and cotton.

Second staple food of pakistan .

Annual local consumption crosses 2.5 million tons.

Contributes about 1.6 percent to the country’s gross domestic product

The per acre yield is 26 to 27 mounds.

Rice production in Punjab • Area (thousand acre) thousand hactare

Year Bsmati Fine rice

IRRI coarse rice

2006-07 1474.24 (3643) 138.81 (343)

2007-08 1377.12 (3403) 159.85 (395)

2008-09 1548.30 (3826) 202.34 (500)

2009-10 1413.95(3494) 218.93 (541)

2010-2011 1313.59 (3248) 174.27 (443)

Production of rice in punjab (1000 metric tonne)

Year Basmati IRRI2006-07 2493.63 334.412007-08 2453.15 414.372008-09 2601.65 517.662009-10 2475.43 532.152010-11 2323.43 435.15

Botanical classification

Botanical Name : Oryza sativa L. Family : Gramineae/ PoaceaeKingdom: PlantaeDivision: MagnoliophytaClass: LiliopsidaOrder: PoalesGenus: OryzaSpecies Sativa

Rice plant

Rice plant is an annual,

2 to 6 ft (61–183 cm) tall, round, jointed stem, long, pointed leaves,edible seeds borne in a dense head on separate stalks.Long day plantSelf pollinated

Rice seed

STRUCTURE OF RICE SEED

STRUCTURE OF RICE SEED

PANICLE OF RICE

Growth stages of rice

GerminationSeedling growthTilleringStem elongationBootingInflorescenceAnthesis

Milk developmentDough developmentRipening

Germination

Seedling growth

Tillering

Stem elongation

Booting

Inflorescence of rice

Anthesis

Milk development

Dough development

Ripening

Factors responsible for rice yield Selection and preparation of soilSelection of approved varietiesSeed rateSowing and transplantation of nursery Irrigation on proper time Proper use of fertilizersWeeds management Important diseases of rice and their control

Harmful insects and their controlHarvesting at proper time

Rice varieties

provinces Fine varieties Coarse varieties

Punjab Super Basmati, Basmati 2000, Basmati Pak (karnal Basmati), Basmati 370, Basmati 515

KSK 282, NIAB IRRI 9, KSK 133

Sind Shadasb, Khushboo, Sada Hayat,

Kinoo 92, DR-82, DR 83, DR-92

KPK JP-5, Basmati 385, Sawat-1, Sawat-2, IRRI-6, KS-282, Fakhar Malakand

Balochistan Basmati-386 IRRI-6 DR-83 KS-282,

Soil

Can be grown in type of soil exept sandy soil.

Can be grown on salt effected soil where other crops can not be grown successfully.

Clay Loam soil with optimum quantity of organic matter and more water holding capacity is best for rice cultivation.

Climate

Can be grown under variety of climate,tropical regionscooler regions temperate regions.humid climate.Best suited to regions, which have high

humidity, prolong sunshine and an assured supply of water.

Rice Nursery and Early Crop Management

Seed Rate for nursery (kg/acre)

Sr. No Rice varieties Wet method

Dry method

Rabi method

1 IRRI 6,KSK 282, KSK 133

6-7 8-10 12-15

2 Supper Basmati, Basmati 385, Basmati 2000,

4.5-5 6-7 10-12

Sowing and transplanting time of nursery

Sr. No Rice varieties Sowing time Transplanting time

1 IRRI 6,KSK 282, KSK 133 20 May to 7 June

20 June 7 July

2 Supper Basmati, Basmati 385, Basmati 2000,

20 May to 20 June

20 May to 20 July

Seed dressing

Seed dressing is done to control diseases e.g,BlastBakanaeStem rotIt is done by soaking the seed into water

contain fungicide 2.5 g/ L water

What is the goal of Crop Establishment?What is the goal of Crop Establishment?

To secure a uniform plant population that can produce high yields

Methods of sowing nursaryWET BEDIrrigate, plow, puddle and level the fieldPrepare beds of 1 to 1.5 m width, 4-5 cm

height & any convenient lengthStart preparing the seedbed 2 weeks before

planting timeSeedlings are ready for transplanting in 25-35

days.

Water the seedbed 2-3 DAS .\Maintain a water level of 2-5 cm, depending

on the height of seedlingsApply 20-40 g urea or DAP per m2 at 10 DAS, if

needed

Wet-bed Rice NurseryWet-bed Rice Nursery

Wet-bed Rice NurseryWet-bed Rice Nursery

• DRY BED methodBed is prepared in dry conditionsWater the seedbed till saturation after sowingThen water the plots periodically as seedlings

emerge & growThis method is practiced in areas where soils

are loamy or silt loam.Puddling is not possible.

DRY BED

Dry-bed Rice NurseryDry-bed Rice Nursery

Rabi method of nursery sowing

Practiced in D.G. khan Areas where soil is hardUprooting of nursery is not possibleNursery plots are leveledCrop residue spread then burnt

Rabi method

Para shoot rice nursery

Para shoot rice nursery: What are the : What are the limitations?limitations?

Farmers have to buy plastic traysHeavy rains just after SB may disturb the

distribution of broadcasted seedlings

IRRI: Rice Production Course

TransplantingTransplanting: :

Most common method Most common method in small farms of Asiain small farms of Asia

TRANSPLANTING OF RICE

IRC 2003:1914

Transplanting: Critical FactorsTransplanting: Critical Factors• Proper nursery management• Careful handling of young seedlings for fast revival

and early growth after TP• Shallow transplanting at 1-2 cm depth• Optimum plant-to-plant spacing: 20 x 20 cm to 25 x

25 cm• Optimum number of seedlings: 1-2 hill-1



TP: Careful Handling of TP: Careful Handling of SeedlingsSeedlings

Manual Transplanting: what Manual Transplanting: what are the advantages?are the advantages?

Good head start forplant growth overweeds

Shorter duration inmain field

Easy to maintainuniform plant spacing& population, ifplanted in rows

Manual TP: What are the Manual TP: What are the constraints?constraints?

Tedious & labor intensive, > 30 PD ha-1

Difficult to find labor to plant on time

Drudgery & back problem

Poor plant population due to contract TP on area basis


Manual PlanterManual Planter

Chinese planter

Japanese planter

Para shoot rice nursery transplanting-manually

IRRI: Rice Production CourseSource: Dr. Sumith, RRDI, SL

Para shoot rice nursery transplanting-manually

Para shoot rice nursery transplanting withMachine

Para shoot nursery : What are the Para shoot nursery : What are the advantagesadvantages

Low seed rate: 15-20 kg ha-1

Less labor for CE (16 for SB vs. 30-36 for TP)No bird damage in the nursery and main

fieldEarly crop maturity by 7-8 days

Water saving: 10 irrigations for SBR vs. 12

for TPR

Less use of agro-chemicals as they can be applied directly to the nursery

Advantages & Disadvantages

The young rice plant is raised in a small seed bed, so it can receive intensive care and protection

The field can be used to grow other thing according to the time taken to grow the rice.

Increase of crop collected per unit area because the caring of the farm will be held intensively.

Need a lot of water to grow crop

Need to take care Weak to pesticides

Advantages Disadvantages

Direct Seeding of Rice: Why?Direct Seeding of Rice: Why?

• To reduce labor input• To tackle labor shortage &

high wages• To establish crops on time• To maintain optimum

plant population


Direct Seeding of Rice: IncentivesDirect Seeding of Rice: Incentives

Increasing water crisis is forcing farmers and researchers to find out ways to decrease water use in rice production.

In Asia, irrigated agriculture accounts for 90% of total diverted freshwater, and more than 50% of this is required to irrigate rice.

Direct seeding offers a promising solution for this by saving water and labor

Direct seeding is a potential alternative to the traditional production system

Reduced cost: US$ 60-80 per ha Less methane emission: DDS < WDS < TP

Direct Seeding RequirementsDirect Seeding Requirements

• Good Land Prepration & leveling

• Furrows to drain water• Saturated soil (WDS) &

moist soil (DDS) for first 7-10 days


• Varieties: early seedling vigor, fast canopy dev., non-lodging

• Quality seed• Effective weed control: cultural, mechanical,

herbicides

Level field for DDS Level field for WDS

Well-prepared and Leveled Fields for Direct Seeding

Direct Seeding MethodsDirect Seeding Methods• Wet direct seeding (WDS): puddled soil,

broadcast- or row-seeded> Surface WDS> Subsurface WDS> Water seeding

• Dry direct seeding (DDS): dry/moist soil, broadcast or drilled in rows



Drum seeder, 8 kg wt + 12 kg seed

Drum seeder

Seed hoppers

Seed holes

Dry SeedingDry Seeding Used in rainfed areas Dry seed Seed rate 75 kg ha-1

Germination with rainfall; drought

High pest incidence

Seeding behind plow Machine seeding

Dry broadcasting

Bed PlantingBed Planting

TPR-B: Transplanting TPR-B: Transplanting seedlings on bedseedlings on bed

•Good CE, but more labor

• Good plant growth & uniform tillering

•High yield as that of TPR

• Less water use (by 20-30%) than that of TPR

DSR-B: Dry drill seeding on bedsDSR-B: Dry drill seeding on beds• Fast & efficient seeding, but poor CE

• May need saturated soil for the first 25-30 days

• Micro-nutrient deficiency: Fe, Zn, Cu, etc.

• Severe weed infestation, needs effective herbicides

•Termite problems

•Saving in water (~ 20-30%)

• Conserves rain water & avoids flooding

Water management Judicious use of water is necessaryAt transplanting and one week after depth of

water 3-4 cmHigher water depth is harmfulLower water depth cause dryingSeven days after transplanting depth of water

should be 8 cmWater should remain standing in field

continuously for 25-30 days.

Fertilizer managmentAdequate and timely application of fertilizers is

essentialSoil analysis should be doneIncorporation of green manure crop before

transplanting to increase organic matterAll of P and k and half of the N is incorporated

into soil at the last ploughingRemaining N is top dressed after 30-35 days

Quantity of fertilizer (kg\acre)Type of varieties

N P K Amount of fertilizer at the time of puddling

After transpla-nting

IRRI-6, KSK 282, Niab IRR-9, KSK 133

69 41 32 1.5 Bag Urea+4.5 Bag SSP+1.25 Bag Potassium Sulphate

1.5 Bag of urea after 30-35 days of urea transplanting

Super Basmati, Basmati 2000, Basmati Pak (karnal Basmati), Basmati 370, Basmati 515

57 32 25 1 Bag Urea+3.5 Bag SSP+ Bag Potassium Sulphate

0.5 Bag of urea after 30-25 days

and ¾ bag of urea transplanting

Weeds management

15%-20% losses due to weedsSome time up to 50%Three groups of weeds in riceWeeds of grass familyWeeds of sedge familyBroad leaf weeds

Weeds of grass familySwanky grass (Echinochloa colon)Dhedan ( Echinochloa crusgalli)Khabal grass (Cynodon dactylon)Narro (Paspalum distichum)

Weeds of sedge familyGhoein (Cyperus difformus)Bhoein (Cyperus iria)Deela (Cyperus rotundus)

Broad leaf weedsMirch boti (Sphenoclea zeylanica)Chopti (Marsilea minuta)Darai boti (Fclipta bprostata)

Swanky grass (Echinochloa colon)

Common Name: Bermudagrass

Scientific Name: Cynodon dactylon mudagrass

Bhoein (Cyperus iria)

Mirch boti (Sphenoclea zeylanica)

INTEGRATED WEED MANAGEMENT (IWM)

IWM is aimed to reduce weed population to the level at which there would be no economical losses of crop.

Effective IWM combines preventive, cultural, mechanical and biological weed management methods in an effective, economical and ecologically safe manner.

weed management technologies can optimize rice production.

Holistic multi-disciplinary integrated approach is necessary.

combination of various weed management methods together is called integrated weed management (IWM).

• Weeds are allowed to emerge and are

then killed during tillage operations.

• First weeding should be done between

15 to 21 days after germination. Second

weeding is done 30 to 45 days after first

weeding.

Application of mulch reduces weed growth and conserve moisture and fertilizers.

Use of weed free seed material is recommended for better weed management.

Maintaining 5–7 cm water depth and

avoiding drainage prevents germination

of weed seeds.

Azolla can suppress the weed growth

by reducing sunlight and aeration.

Herbicide should be applied when

there is a thin film of water in the field

Application of pendimethalin 1.0kg/ha on

5 days after sowing

Pretilachlor + Safener (Sofit) 0.45kg/ha

on the day of receipt of soaking rain

followed by one hand weeding on 30 to 35

days after sowing effectively controls

weeds in kharif season.

Advantages of Weed

ControlIncrease in yield

Conservation of soil moisture

through reduced competition for

sunlight, nutrients and water.

Reduced incidences of pest and disease

INSECTS MANAGEMENT

Dark-headed stem borer (Chilo polychrysus)

Larva

• Neonate - grayish white with a large head. • Head and prothoracic shield are black. • Body dirty white with five longitudinal stripes

of grayish violet or purplish brown situated mid- dorsally, latero-dorsally, and laterally.

Adult

• Adults brownish yellow. • The center of the forewings has dark

markings of silvery scales or 6-7 tiny black dots.

• The hind wing has a lighter color.

• LarvaThe larva is whitish to light yellow. A full-grown larva is 25 mm long. The larva has no body marks.

• PupaThe fresh pupa is soft-bodied and whitish. It grows up to 25 mm in length. With age, it turns brown.

• AdultThe male and female adults are immaculately white in appearance. They have a tuft of long hairs on the thorax. The male is smaller than the female.

White stem borer (Scirpophaga innotata)

Yellow stem borer : Scirpophaga incertulas (Walker)

Most destructive pest. Attack all stages of the rice plant 1% to 19% yield loss in early planted rice crops and 38% to 80% yield loss in late-planted rice.

Low infestations by stem borers may not result in yield loss because of plant compensation.

Sprays for stem borer control carried out when whiteheads are visible will not result in any economic gain.

Adult The female is whitish to yellowish. Has a pair of clear black spots at the middle

of each forewing. The male is smaller and dull in color. It has

two rows of black spots at the tip of the forewings.

The male’s wingspan is about 20-30 mm, whereas the female’s is 24-36 mm.

The female’s abdomen is wide with tufts of yellowish hairs all over. The male has a slender abdomen toward its anal end and is covered with thin hairs dorsally.

EggIndividual eggs are white, oval, flattened, and covered with brownish hairs from the anal tufts of the female.

LarvaThe larval body is yellowish green. The head and prothoracic shield of a full-grown larva are brown. The larva passes through six instars. The first instar is about 1.5 mm long and the last instar 20 mm long.

Pupa

The pupa is pale green. It is about 12 mm long and 3 mm wide. The pupa is enclosed in a white silk cocoon. When newly formed, the cocoon is pale brown. It gradually turns dark brown.

Adult

The forewings are bright pale brown with some scattered dark brown markings.

A purplish red band radiates from the central point in the forewing to the wing tip.

Light stripes border the wing apex. The hind wings are whitish with light

yellow scales along the major veins.

Pink stem borer Sesamia inferens

Larva

Newly hatched larvae are white with a yellowish tinge and a black head capsule.

Mature larvae turn pinkish purple with a brown or orange-red head capsule.

The body has no longitudinal stripes. Measures 25.0 to 35.0 mm long and 3.0 mm wide.

PupaThe pupa is brown to dark brown with a tinge of bluish powdery substance.

Adult The adults are brownish

yellow with silvery scales A row of 7 or 8 small black

dots at the terminal margin of each forewing.

The forewings are darker than the hindwings.

Striped stem borer : Chilo suppressalis

Egg

Larva

Neonate larvae have a large head. Head and prothracic shields are shiny

brown or orange. Body is light brown or pink with five rows of

longitudinal stripes, which run the entire length of the body.

The stripes are brown or pale purple, situated dorsally and laterally.

The full-grown larvae measure 20 to 25 mm long.

Pupa The pupa is reddish brown. It measures about 11 to 13.5 mm long. Several spines are prominent on the last

segment of the pupa.

Common in rice ecosystems. Infests at the early crop stages. Population densities are usually insufficient to cause

significant losses in yield. Crops generally recover from this damage.

Insecticide use have little or no economic returns.

Rice leaf folder : Cnaphalocrocis medinalis

EggThe newly laid egg is jelly-like and transparent. It is oblong with an irregular upper surface. The mature egg is ovoid and whitish yellow. It is ventrally flattened.

LarvaNeonate larvae are yellow. With age, they turn yellowish green with brown heads. They have distinct pinnaculae or one pair of subdorsal spots on the mesonotum. The apex of their pronotum is always straight. They are from 12 to 25 mm long.

The male moth has a thick black hair tuft on its fore tibia. The dorsal part of its abdominal tip has a thin and very long longitudinal black band. The male has a wingspan of 14 to 16 mm.The female moth has a longer wingspan of 16 to 18 mm.

PupaThe pupa is light brown or bright brown. With age, it turns reddish brown. It is 9 to 12 mm long.

AdultThe adult is whitish yellow or golden yellow. It has three black bands on the forewings, two are complete bands and one is an incomplete middle band.

Feeding damage of the rice leaf folder includes folded leaves and removal of leaf tissue, leaving longitudinal and transparent streaks. The streaks are whitish.

The folded leaves are tubular where the larvae conceal themselves to feed. Sometimes, the tips are fastened to the basal part of the leaf.

Heavily infested fields show many folded leaves and a scorched appearance of leaf blades.

Nature of damage

Rice hispa : Dicladispa (= Hispa) armigera Olivier

• Causes leaf defoliation damage to rice crops over large areas in Bangladesh, India, and Indonesia.

• Extensively damaged plants may be less vigorous and stunted.

• The rice hispa seems to be a perpetual problem in Bangladesh. It infests about 120,000 hectares, causing an estimated loss of 20% in yield.

AdultThe adult is blue-black and very shiny. Its wings have many spines. It is 5.5 mm long.

EggThe white egg is small and oval. It measures 1-1.5 mm long. A small dark substance secreted by the female covers each egg. As the egg matures, it turns yellow.

PupaThe brown pupa is round and about 4.6 mm long.

LarvaThe larva or grub is white to pale yellow. A younger grub measures 2.5 mm long, whereas a mature larva is about 5.5 mm long and 1.6 mm broad.

• Both adults and grubs feed on and damage the plants. • The adults scrape the upper surface of the leaf blade leaving

the lower epidermis. • Damaged areas appear as white streaks parallel to the midrib. • Tunneling of the grubs results in irregular translucent white

patches. • The affected parts wither off. • The leaves also turn whitish and membranous. • Severe infestation causes the field to appear burned.

Nature of damage

Plant hoppersBrown plant hopper (BPH) (Nilaparvatha lugens)White backed planthopper (WBPH) (Sogatella furcifera)

Brown planthoppers (BPH) suck the sap of the leaf blades and leaf sheaths, causing the yellowing of the plants. Hopperburn or complete drying of the plants is observed at a high population density of the insects. At this level, the loss is considered 100%.

AdultsThe adult is brownish black with a distinct white band on its mesonotum and dark brown outer sides. The body is yellowish brown. The adults have two distinct winged forms, macropterous and brachypterous. Macropterous forms have normal front and hind wings, whereas brachypterous forms have reduced hind wings.

Eggsare crescent-shaped, 0.99 mm long and 0.2 mm wide. Some of the eggs are united near the base of the egg cap and others remain free. When freshly laid, the eggs are whitish, but later become darker. Before egg hatching, two distinct spots appear, representing the eyes of the developing nymph.

NymphsThe newly hatched nymphs are 0.91 mm long and 0.37 mm wide. The head is triangular with a narrow vertex. The body is creamy white with a pale brown tinge. The nymphs molt five times. The fully developed nymph is 2.99 mm long and 1.25 mm wide. There is a prominent median line from the base of the vertex to the end of the metathorax where it is the widest. This line crosses at a right angle to the partition line between the prothorax and mesothorax.

• Both BPH and WBPH nymphs and adults damage the plants by sucking phloem sap

• Reduced vigour, stunting, yellowing, delayed tillering and grain formation.

• At later stages, crop dries up in patches known as hopper burn.

• BPH also transmit virus disease called grassy stunt.

Nature of damage

• Leaf hoppers adult and nymphs suck the sap from the leaves which is characterized by small scratch like marks on the leaf due to chlorophyll removal.

Leaf hoppers

Green leaf hopper Nephotettix virescensN. nigropictus

Zigzag leaf hopper Racilia dorsalis

EIL 10 GLH/hill at vegetative stage 20 GLH/hill at flowering stage

Nephotettix nigropictus

AdultThe adult is slender and green with a rounded vertex.

Vertex has an anterior black band and a sub-marginal black band extending beyond the ocelli to the inner margins of the eyes.

Its pronotum is smooth with a black anterior margin. Black spots are prominent on the forewings. The female hopper measures 4.3 by 1.4 mm, whereas the male is 3.7 by 1.3 mm.

Less efficient virus transmitter Transmits tungro, yellow dwarf, dwarf, and transitory

yellowing diseases.

Green leafhoppers are important pests. They are vectors of viruses such as tungro, yellow dwarf, and transitory yellowing.

The adult leafhopper is green. Its head has a pointed vertex

without black bands. The face is also green. A pair of black spots is either

present or absent on the tegmen of the forewings.

A male hopper measures 4.2 by 0.05 mm, whereas the female is 4.3 by 1.4 mm.

Nephotettix virescens

Recilia dorsalis

In large numbers, this insect can transmit rice tungro, rice dwarf, and rice orange leaf viruses

Adult hoppers has zigzag white and brown pattern on the front wings.

The body of the female adult is 3.5-3.8 mm long, whereas the male is 3.1-3.4 mm long.

This sporadic pest occasionally causes losses. It can be destructive when an outbreak occurs. Mature panicles are cut off from the base or peduncles. The host plant may be totally devoured when populations are very high.

Caterpillars feed on leaves in night and in severe infestation entire seed beds and fields are destroyed and the field appears as if it has been grazed by animals/ cattle

Rice armyworm :: Mythimna separata (Walker)

EggThe eggs are subspherical and greenish white. With age, they turn yellow.

AdultThe adult is more than 15.0 mm in length. Its forewings are pale red-brown with two pale round spots. Its hindwings have two colors, dark red-brown on top and white underneath.

LarvaYoung larvae have two pairs of prolegs. Mature larvae are green to pink with longitudinal light gray to black stripes running along the entire length of the body. They are 31.0 to 45.0 mm long. They have a brown to orange head with an A-marking on the frons.

PupaThe pupa is 17.0 to 20.0 mm long. It is dark brown.

The larvae feed on the leaves by removing the epidermis leaving the leaf tissues. Excessive feeding causes complete removal of whole leaves and plants. The rice panicles can also be cut off from the peduncles.

Nature of damage

Rice thrips : Stenchaetothrips biformis

This is a pest during the seedling stage or 2 weeks after early sowing. It is a serious pest during the dry season.

Losses can reach 100% where infestation is severe for the first 20 days in direct-seeded rice fields.

• EggThe egg is very tiny. A single egg is 0.25 mm long and 0.1 mm wide. It is hyaline when freshly laid and turns pale yellow toward maturation.

• LarvaNeonate larvae are colorless. They become pale yellow in the second larval instar. The legs, head, and antennae of the second instar larvae are slightly darker than those of the first instar larvae.

• PrepupaThe prepupa is brown. Four pointed processes are present on the hind margin of the ninth abdominal tergite.

• PupaThe pupa has long wing pads that reach two-thirds the length of the abdomen. It also has four pointed processes on the ninth abdominal tergite.

• AdultThe minute adult has a slender body. It is dark brown. It is 1-2 mm long with well-pronounced 5 to 8 segmented antennae. It exists in two forms, winged or wingless. The winged form has two pairs of elongated narrow wings that are fringed with long hairs.

.

Nature of damage

• Feeding damage causes laceration of plant tissues.• Damaged leaves become noticeable as silvery streaks or

yellowish patches.• The translucent epidermis becomes visible on the

damaged area. • Curling of the leaves from the margin to the middle is

also visible.• In severe infestation, the leaf tips wither off.• Infestation at the panicle stage causes unfilled grains

Both the nymphs and adults feed on the leaf and can consume large amounts of leaves.

Grasshopper : Oxya hyla intricata

AdultOxya hyla intricata are small to medium and moderately slender insects. They measure up to 20 mm in length. Their eyes are large and close to each other. They have a sub-cylindrical pronotum with a rounded posterior margin. The height of the pronotum is lower than the head. Their wings are fully developed in both sexes. Their green hind femora are slender with upper knee lobes rounded and lower knee lobes extended into acute spine-like projections. They have greenish tibiae. Their wings are green with brownish to bluish bands.The antennae are filiform in type. The antennae of the male are slightly longer than the head and pronotum combined. The female has shorter antennae.

EggThe eggs are capsule-like and yellow.

NymphThe nymph is a smaller version of the adult except for the presence of small wing pads.

Integrated Disease Integrated Disease Management in RiceManagement in Rice

Major Diseases of RiceMajor Diseases of Rice

• Blast (Pyricularia oryzae)• Brown spot (Helminthosporium oryzae)• Stem rot (Sclerotium oryzae)• Bacterial leaf blight (Xanthomonas oryzae)

Symptoms of Blast Disease

Blast diseaseBlast disease• Most plant parts are susceptible to infection except the

roots.• Disease usually develops during seedling, tillering (leaf blast)

and at heading (panicle blast).• The initial infections start as small water soaked areas on

young leaves and enlarge into diamond shape with a blue gray cast which are the fungal spores. Lesions often dry out and turn tan with a brown border. Lesion shape and size can vary.

Head infections develop at the joint just below the head (neck blast) or on individual panicle branches (panicle blast). The head can break off at neck lesion can cause rotten neck blast.

The fungus produces many spores ,on stalk like structures called sporangia, in the presence of a favorable environment and a susceptible host and causes numerous new infections in the field and neighboring fields. They are carried by wind and water over long distances.

ManagementManagement

• Blast development is favored by thick stands and high nitrogen rates which increase canopy thickness resulting in higher moisture levels but is most severe under upland or drained conditions. Other conditions that favor blast are sandy soils and fields lined with trees.

Management contd.Management contd.

• Plant varieties resistant to blast. • Avoid late planting. • Plant as early as possible within the

recommended planting period. • For leaf blast, re-flood if field has been

drained. Maintain flood at 4 -6 inches to ensure soil is covered.

• Do not over fertilize with nitrogen. • Apply a fungicide if necessary.

Brown spotBrown spot

Management of brown spotManagement of brown spot

• Treat the seeds with 0.2% Thiram• Avoid water stress• Give balanced nutrition• Use resistant varieties• Spray Tricyclazole

Stem rotStem rot

Black angular lesions on leaf sheath at or near water line on plants at tillering or early jointing growth stages; later sheath may dye and culms have dark-brown or black streaks, at maturity culms may collapse and small round black sclerotia form in dead tissues.

ManagementManagement

• Fungicides are available to control stem rot however infestation levels seldom reach economic levels to justify spraying and no economic thresholds have been developed. Stem rot is usually detected when scouting for sheath blight. Fungicide applications targeted at other diseases can reduce stem rot severity.

Foot rot/ Bakanae

• Caused by fungus Fusarium moniliforme.• The general symptoms of this disease is that

infected plants die at grain filling period, and they bear only white empty panicles.

• A white or pink growth of the pathogenic fungus may be noticed on the lower parts of diseased plants.

• Some other symptoms may be observed in early stages: infected seedlings are taller than normal plants and are thin and yellowish-green at the seedling stage,

• Bakanae symptoms can be seen in the vegetative stage, infected plants are taller than the normal plants and have a few tillers and yellow-green leaves.

• The most important damage occurs at the grain filling period.

Foot rot/ SymptomsFoot rot/ Symptoms

Management

• Produce basmati seed from disease free aress.• Treat seed with suitable fungicide e.g. Benlate• Destroy stubble and crop debris.• Rogue out infected plants• Adopt crop rotation• Grow less susceptible varieties• Use balance fertilizers

Bacterial blight

• Symptoms • Small, green water-soaked spots develop at the

tips and margins of fully developed leaves, and then expand along the veins, merge and become chlorotic then necrotic forming opaque,

• White to grey colored lesions that extend from leaf tip down along the leaf veins and margins. Both bacterial blight and bacterial leaf streak can occur simultaneously and are difficult to distinguish

. caused by Xanthomonas oryzae

Factors favoring disease development

• presence of weeds• presence of rice stubbles and ratoons of infected plants• presence of bacteria in the rice paddy and irrigation canals• warm temperature, high humidity, rain and deep water• over fertilization• handling of seedlings at transplanting

Management principles

• Practicing field sanitation such as removing weed hosts, rice straws, ratoons, and volunteer seedlings is important to avoid infection caused by this disease.

• Likewise, maintaining shallow water in nursery beds, providing good drainage during severe flooding, plowing under rice stubble and straw following harvest are also management practices that can be followed

. Proper application of fertilizer, especially nitrogen, and proper plant spacing are recommended for the management of bacterial leaf blight.

Harvesting

Harvesting at proper time ensure grain quality, a high market value and improved consumer acceptance.

Harvesting should be done between 27 to 39 days after flowering.

Harvesting is done by• Manual with sickle• By using Combine harvester

Content

• Introduction• What is harvesting• Harvesting systems• When to harvest• How to harvest

(technology options)• Harvest losses• Recommendations

Introduction

Harvesting is the process of collecting the mature rice crop from the field.

• Cutting: cutting the panicles and straw.• Hauling: moving the cut crop to the threshing

location.• Threshing: separating the paddy grain from

the rest of the cut crop.• Cleaning: removing immature, unfilled and

non-grain materials.• Field drying: (optional) leaving the cut crop in

the field and exposing it to the sun for drying.• Stacking / Piling: (optional) temporarily

storing the harvested crop in stacks or piles.

Good harvesting practices

Goals of good harvesting:• maximize grain yield

(minimize losses)• minimize grain damage • Minimize quality

deterioration

• Heat build up from mold and insect development

• Discoloration/Yellowing from heat build-up

• Cracking from re-wetting of dried grains

• Loss of vigor• Reduced head rice yield• Shattering losses

At harvest the quality of rice is best. From then on it can deteriorate quickly:

Harvesting systems1. Manual system

• Manual operation sometimes using tools

• Labor requirement: 48 person days / ha

Harvesting systems2. Manual cutting / machine threshing

• Labor requirement: 28 person days/ha• Capital cost appr.: US$ 1000

Optional:Winnowing or cleaning

Harvesting systems2. Machine cutting / machine threshing

• Capacity reaper: • Capacity thresher: • Capital cost approx.: US$ 2,500

Optional:Winnowing or cleaning

Harvesting systems4. Combine harvesting

• Cutting, hauling, threshing, cleaning in one combined operation

• Capacity: > 0.5 ha/h• Labor requirement: 1

Operator• Capital cost: > $

250,000

When to harvest

Harvest rice when:• 20-25% grain moisture• 80-85% straw colored and• the grains in the lower part

of the panicle are in the hard dough stage

• 30 days after flowering

Manual cutting and hauling

• Capacity: 0.07 ha/person day• Advantages

– effective in lodged crop– less weather dependent

• Problems– high labor cost– labor dependent, competes with

other operations in peak season– winnowing/cleaning necessary

Mechanical reaping

• Capacity: 2-4 ha/d• Advantages

– Fast cutting• Problems

– Places crop in window back in the field

– Problem with lodged crop

– Complex cutter bar and conveying mechanism

Manual threshing

• Capacity: approximately 15 person days/ha

• Threshing by impact• High shattering losses• Pre-drying might be

needed

Pedal thresher

• Capacity: • Principle

– Wire loop threshing drum– Mainly combing the grains

off the straw, some threshing by impact

• Advantages– Maintains the straw

• Disadvantage– Needs winnowing after

threshingWire loop threshing drum

Axial-flow thresher

• Capacity: 0.3-3t/h• Threshing through

impact• Large range of sizes

available• With or without cleaner• Truck mounted units• Advantages

– Can thresh wet crop– Compact

produced in 9 different countriesused by several 100,000’s of rice farmers across Asia

Peg tooth threshing drumAxial flow principle

Winnowing

• Principle: lighter materials are blown away by air

• Removes chaff, straw and empty grains

• Hand or mechanical winnowing

• Does not work for materials heavier than grain (dirt, stones)

Cleaning

• Combination of fan and oscillating sieves

• Air delivered by fan removes lighter materials

• Top sieves with large holes remove larger straw particles

• Bottom sieves with smaller holes remove small seeds (e.g. weed seeds)

Combine harvesting

• Features– capacity: 4-8 ha/day– combines cutting, threshing,

cleaning and hauling– tracks for mobility in wet fields

• Advantages– high capacity– low total harvest losses

• Disadvantages– Requires relatively large field sizes– Problem in terraced fields

Stripper harvesting

• Capacity: 1ha/day• Advantages

– strips and collects grains only

– less material to handle• Problems

– problems in wet soils and lodged crop

– straw treatment– does not work well

with long straw– complex machine– skills required

Despite strong promotion in SE-Asia the stripper harvester has not gained wide popularity because of its problems in less favorable harvesting conditions

Losses during cutting• Shattering loss = premature shedding of mature

grains from the panicle caused by birds, wind, rats, and handling operations. Certain rice varieties shatter more easily than others.

• Lodging loss = plants with mature grains in the panicles fall on the ground making the grains difficult to recover.

• Standing crop loss = standing plants with mature grains are left standing in the field after harvesting operations as a result of oversight, carelessness or haste.

Losses during threshing

• Separation loss or “blower loss” = mature grains that are mixed with straw or chaff during the cleaning operation.

• Scatter loss = mature grains that are scattered on the ground during the threshing and cleaning operation.

• Threshing loss = mature grains that remain attached to the panicle in the straw after completion of the threshing operation. High threshing efficiency will lead to low threshing loss, and vice versa.

Recommendations for optimizing quality

• Harvest at the right time and moisture content• Avoid stacking the cut crop in the field• Avoid delays in threshing after harvesting• Use the proper machine settings when using a

threshing machine• Clean the grain properly after threshing • Avoid delay in drying after threshing

Tips for manual threshing

• Thresh as soon as possible after cutting

• Hand thresh at lower moisture

• Place a large canvas under the threshing frame to minimize shatter loss

Tips for machine threshing

• Thresh as soon as possible after cutting

• Level the thresher• Set machine correctly

– drum speeds in thresher (600rpm)

– air flow in the cleaner– angle in the cleaner

sieves

Tips for good winnowing

• Place grain on a winnowing tray• Place a net or mat on the ground• Tilt the tray against the wind• Pour grain slowly at a height of about

1m• Wind will separate light from heavy

grains• Recover only the heavier grains• Repeat the procedure, if needed• Use a fan or blower if there is

insufficient wind.

THANKSTHANKS

Food

Rice lecture final