• An insect whose population increases to such an extent as to cause economic losses to crops or a nuisance and health hazard to man and livestock is termed as an insect pest.
• An insect may be a pest at one place but may not be so at another place.
• Insects injure plants by feeding on them and laying eggs in plant tissues. Losses from insect feeding may be direct or indirect.
• An orbitary limit of a pest population responsible to cause 5 per cent loss in any crops yield is called the pest status.
• Insects that cause a loss of 5 to 10 per cent are considered minor pests and those that cause a loss of 10 per cent and above are considered to be major pests.
• Besides, insects other invertebrates like nematodes, mites, snails, slugs, etc. vertebrates like rats, birds, jackals also cause damage to rice.

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Mites and Brown Wheat Mite

Damage:

• Rarely damage is moderate to high.
• These are about 1.00 mm in length and have sucking mouthparts.



The mites cause silver flecking in the leaves, web like structures may also be produced on the leaves.



• The plants show stunted growth and they also head poorly and may also turn pale or white in colour.
• In later stages the plant gives sick appearance.

Control:

• Chemical insecticides should only be applied if the insect population crosses the economic threshold level (ETL).
• Spraying of Dimethoate @ 200 - 250 gm/ha OR* Spraying of Monocrotophos @ 200 - 250 gm /ha Or Spraying of Oxydsemeton methyl @ 200 - 250 gm/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.
• Always use hollow cone nozzle for spraying.

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Aphid and Root Aphids: Macrosiphum miscanthi

Schizaphia graminum, Rhopalosiphum rufiabdominalis, R.maidis and other spp.

Damage:

• This insect is active from Nov to Feb.
• Damage is more in rain fed and late sown crop.
• These are the sucking insects of the wheat crop.
• These are nearly transparent insects, very small and have a soft body.
• Due to voracious sucking of the plant sap the leaves die or mature prematurely.

It causes direct feeding damage that appears brown and discolored. Damaged leaves will often appear slightly curled or speckled at worst.

• These aphids present in large numbers on flag leaves and developing grain heads.
• Damage from this pest often results in low-test weight grain.
• In case of root aphids yellowing of young plants is observed.
• In this case minute yellowish brown aphids may be present near the base or on the roots of the plant.
• Aphids also vector a viral disease named barley yellow dwarf virus (BYD). Yield of infected wheat plants can be reduced by 50%.

Control:

Cultural:

• Avoid late sowing.
• Avoid use excess nitrogen fertilizers.
• Keep supervision of crops in case of aphids.
• At the initial stage spraying of borders of field with insecticide will help in reducing the aphid population.

Chemical:

• Chemical insecticides should only be applied if the insect population crosses the economic threshold level (ETL).
• ETL for aphids is 5 aphids per ear head.
• Treat the seed with Endosulfan 35EC 4ml/kg of seed.
• If the infestation in standing crop, Spray 200 - 250 gm/ha of Dimethoate or Oxydemeton methyl, or monocrotophos.or chloropyriphos 1200ml/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.

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Army Worm Mythemna seprata

Damage:

• The insect attack is observed in rice wheat cropping system.
• The attack is normally in the early stages of the crop.
• The insect has chewing type of mouth parts.
• Complete defoliation of the wheat plant occurs when this insect attacks the wheat plant. Severe infestation will leave only a stalk standing in the field.

Young larvae feed on the leaves and then attack the stem. The larvae generally attack the plant during the night and it hides or stays it rests during the daytime. They feed late in the afternoon and at night on leaf tissue. They often will cut off about as much foliage as they eat.

• When the weather is cloudy or dampness is there then the insect may attack the plant whole day.
• Greyish striped caterpillar below the ground level is observed.
• Larvae have three, orange, white and brown stripes running the length of each side.
• The larvae will also have a narrow broken stripe down the center of its back.
• The presence of black spots located at the top of the four pairs of prolegs.
• In adult plants awns are cut and completely eaten up.
• They will also feed on the tips of the developing wheat seeds causing lower yields and lighter test weights.

Control Measures:

Cultural:

• Do not use nitrogen fertilizer in excess as it attracts the higher population of armyworm.
• Avoid late sowing of wheat crop.

Chemical:

• ETL for armyworm is 4 - 5 larvae per metre row.
• For effective control of armyworm spray any one of the following insecticides particularly in the evening.
• Carbaryl at the rate of 750 -1000 gm/ha. / Fenitrothion at the rate of 750 gm/ha/ Dicholorvos at the rate of 500 gm/ha. / Quinalphos at the rate of 400 gm/ha. / Trichlorophon at the rate of 750 gm/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.

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Cereal Leaf Beetle of Wheat Oulema melanopa

Damage:

• The wheat crops with non-hairy leaves are generally affected more.

The adult as well as the larvae is the damaging stage of the insect.

• The adult is 4 to 5 mm in length and has black headlight brown thorax and a shiny blue green wing cover having parallel lines of small dots.
• The larvae are dull to bright yellow in colour.
• Symptoms include appearance of longitudinal stripes on the leaves.

Control Measures:

Cultural:

• Practice deep summer ploughing to expose soil to solar radiation.
• Use tolerant varieties if available.
• Always use certified clean seeds recommended for your zone.
• Avoid late sowing of crop.
• Always use well rotten manures.
• Apply recommended dose of fertilizers




Chemical:

• Spray any one of the following insecticide.
• Dimethoate (rogor 30 EC) at the rate of 330 ml/haOR Methyl Dematon 25 EC at the rate of 650 ml/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.

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Hessian Fly Mayetiola destructor

Damage:

• The larvae is the damaging stage of the insect.
• The larvae suck the plant sap from the stem.
• In case of severe infestation the plants turn stunted.

The plant stand is reduced and lodging occurs. Reduction in yield is also noted.

• If the attack occurs during the jointing stage then the stem may break afterwards just prior to the maturity.
• The Hessian fly is 3 - 4 mm in length.
• Its head and thorax is black and has a pinkish yellow brown abdomen.

Control Measures:

Cultural:

• Practice deep summer ploughing to expose soil to solar radiation.
• Use tolerant varieties if available.
• Always use certified clean seeds recommended for your zone.
• Avoid late sowing of crop.
• Always use well rotten manures.
• Apply recommended dose of fertilizers

Chemical:

• Spray any one of the following insecticide.
• Dimethoate (rogor 30 EC) at the rate of 330 ml/ha.
    OR
• Methyl Dematon 25 EC at the rate of 650 ml/ha.

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Various species of Slug Snail Grass hopper of Wheat

Damage:

• These insects have biting and chewing type of mouthparts.
• Generally the adult is the damaging stage of the insect.

The insect usually bites the stem from the portion near the ground. The insects also chew the longitudinal stripes of the leaves.

• The damage depends upon the population of the insects. If the population of the insect is more, damage is caused to the crop.

Control Measures:

Cultural:

• Practice deep summer ploughing to expose soil to solar radiation.
• Use tolerant varieties if available.
• Always use certified clean seeds recommended for your zone.
• Avoid late sowing of crop.
• Always use well rotten manures.
• Apply recommended dose of fertilizers.



Chemical:

• Spray any one of the following insecticide
• Dimethoate (rogor 30 EC) at the rate of 330 ml/ha.
    OR
• Methyl Dematon 25 EC at the rate of 650 ml/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.

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Stink Bug Mezara viridula & other species

Damage:

• Mild cool temperature and low rainfall give this insect favorable condition for growth, reproduction and development.



;	The adult stinkbug is the damaging stage of the insect, this bug feed on the stem and developing kernels.



• The saliva of the stinkbug is poisonous in nature and it may kill the stem.
• If the kernels are fed during the early dough stage the grain is completely destroyed.
• If it is attacked at a later stage then the grain becomes completely shrivelled.

Control Measures:

Cultural:

• Practice deep summer ploughing to expose soil to solar radiation.
• Use tolerant varieties if available.
• Always use certified clean seeds recommended for your zone.
• Avoid late sowing of crop.
• Always use well rotten manures.
• Apply recommended dose of fertilizers.



Chemical:

• Spray any one of the following insecticide
• Dimethoate (rogor 30 EC) at the rate of 330 ml/ha.
OR
• Methyl Dematon 25 EC at the rate of 650 ml/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.

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Stem Fly/Shoot fly Atherigona bituberculata

Damage:

• Attacks in early and late sown crop.

Control Measures:

Cultural:

• Practice deep summer ploughing to expose soil to solar radiation.
• To avoid insect attack sowing should be done from mid Nov to mid Dec.
• Use tolerant varieties if available.
• Always use certified clean seeds recommended for your zone.
• Avoid late sowing of crop.
• Always use well rotten manures.
• Apply recommended dose of fertilizers

Chemical:

• Spray any one of the following insecticide.
• Spray Cypermetherin 50gm a.i/ha repeat the spray after 15 days.OR Dimethoate (rogor 30 EC) at the rate of 330 ml/ha OR Methyl Dematon 25 EC at the rate of 650 ml/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.

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Stem Maggot

Damage:

• The larva is the main damaging stage of the insect.
• Young larvae bore inside the stem and then eat the stem matter causing the young tillers to fall.
• In case of severe infestation the plant dies.
• The infected plants show white head like condition.
• The adult fly is pale green to yellow in colour with somewhat dark stripes and is about 6 mm in length.

Control Measures:

Cultural:

• Practice deep summer ploughing to expose soil to solar radiation.
• Use tolerant varieties if available.
• Always use certified clean seeds recommended for your zone.
• Avoid late sowing of crop.
• Always use well rotten manures.
• Apply recommended dose of fertilizers.



Chemical:

• Spray any one of the following insecticide.
• Dimethoate (rogor 30 EC) at the rate of 330 ml/ha. OR
• Methyl Dematon 25 EC at the rate of 650 ml/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.

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Thrips Anaphothrips favicinctus and its other species

Damage:

• These are small black and brown insects.
• The mouth parts of these insects are of piercing and sucking type.
• These generally feed on the stem and leave and suck the plant sap.
• The plants and especially the leaves turn pale upon insect infestation.



Control Measures:

Cultural:

• Practice deep summer ploughing to expose soil to solar radiation.
• Use tolerant varieties if available.
• Always use certified clean seeds recommended for your zone.
• Avoid late sowing of crop.
• Always use well rotten manures.
• Apply recommended dose of fertilizers.



Chemical:

• Spray any one of the following insecticide.
• Dimethoate (rogor 30 EC) at the rate of 330 ml/ha. OR
• Methyl Dematon 25 EC at the rate of 650 ml/ha.
• The above spraying should be done by dissolving it in 600 - 700 litre of water.

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Wire worm

Damage:

It attacks in the larva stage and cuts the plant parts from below earth.

Control Measures:

Cultural:

• Practice deep summer ploughing to expose soil to solar radiation.
• Use tolerant varieties if available.
• Always use certified clean seeds recommended for your zone.
• Avoid late sowing of crop.
• Always use well rotten manures.
• Apply recommended dose of fertilizers.

Chemical:

• Apply phorate @ 10kg/ha and give irrigation by sprinkler. or apply Hectachlor 50% solution @ 20kg/ha at the time of sowing.or
• Spray any one of the following insecticide.
• Diamethoate (rogor 30 EC) at the rate of 330 ml/ha. OR
• Methyl Dematon 25 EC at the rate of 650 ml/ha.
• The above spraying should be done by dissolving it in in 600 - 700 litre of water.

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Rodents, Rats and Mice Rattus rattus, R. meltada and Bandicota bengalensis

Damage:

• Rats are the major damage causers of wheat crop.
• Rats eat the grains of wheat and also they carry grains in their burrows for storage.
• Rats cuts the wheat crop just above the ground level and then carry the either the heads or the whole plant with it inside the burrows.
• The economic threshold level for wheat crop in case of rodents is 25 live burrows in one hectare and a damage index of 2 percent tiller damage.
• Incase of breakdown of resistance, the recommended economic threshold level to be taken into consideration.

Control Measures:

Cultural:

• Trimming of the field bunds to destroy the existing rodents burrows.
• Collapsing the existing rodents burrows by flooding or filling etc.
• Employing indigenous rattraps before the crop reaches the primordial stage.
• Employing and affixing bird perches at 5 feet height to attract biocontrol agents like Owls during the night time and these bird perches should be removed just after flowering.
• When the rodent infestation is lees then 25 burrows per hectare apply Bromadiolene 0.005% bait (15 gm per burrow) to be placed inside the live burrow.
• If the rodent population is more place zinc sulphate of 2.0 to 2.5 % poison bait to be placed inside the live burrow at the rate of 10 gm per burrow after pre baiting with plain bait.
• The bait material may be the common grain of that particular area.
• This control operation may be done at the milk stage of the crop.

Chemical:

• Chemical rodenticides should only be applied if the rodent population crosses the economic threshold level (ETL).
• ETL for rodents 25 live burrows/ha.
• Use of poison bait is recommended for effective control of rodents like Bromabiolone at the rate of 0.005 % bait (15gm) per burrow to be placed inside the live burrow.OR
• Zinc phosphide 2 to 2.5 % bait to be placed inside the live burrow at the rate of 10 gm /burrow after pre baiting with plain bait.
• The bait material may be commonly grown cereal of the area.

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Deemak or Termite

Damage:

• The termite damages the crop by eating the grains and plant parts.
• The roots are cut off just below ground level.
• The plant is easily pulled out.

Control Measures:

• Treat the seed at the rate of 4ml Dursban/Ruban/Durmet 20 EC (chlorpyriphos) or 7ml Thiodan 35 EC (endosulfan) or 6ml Regent 5% SC (fipronil) per kg seed.
• Dilute 160ml of Dursban / Ruban/ Durmet / or 280ml Thiodan or 240ml of Regent in one litre water and spray the same on 40kg seed spread as a thin layer on the pucca ground or tarpaulin or polythene.



Note : Insecticides applied against termites would also control root aphid and the Gujhia weevil. Seed treated with Chlorpyriphos is less attacked by birds.

• If the attack is noticed in the standing crop dilute, 1 litre of Thiodan 35EC in 2 litres of water and mix it with 20kg of soil and broadcast evenly in one acre. This method is suitable for rainfed crop.
• In the irrigated crop light irrigation may be applied after broadcasting.

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Stem borer/ Tana chhedak