🐞 IPM for Rice and Cotton

This lesson explains integrated pest management (IPM) strategies for rice and cotton, with emphasis on preventive agronomy, biological control, and threshold-based pesticide use. It consolidates practical ETL references used for field decision-making in BSc Agriculture.

Lecture 29 : IPM (Integrated Pest Management) for Rice

1. Avoid use of excess nitrogenous fertilizer which induces BPH and leaf folder
2. Remove/destroy stubbles after harvest
3. Trim field bunds and keep field free from weeds
4. Control irrigation by intermittent draining to manage BPH (Alternate wetting and

drying of field) 5. Avoid close planting, especially in BPH and leaf folder prone areas/seasons 6. Provide rogue spacing of 30 cm at every 2.5 m interval to take up plant protection

operation 7. Use light traps to monitor incidence of pests 8. Avoid resurgence inducing chemicals against BPH like Methyl parathion and

quinalphos 9. Remove stem borer egg masses by dipping off tip of rice seedling during

transplanting 10. Select and use resistant varieties against major pests 11. Manage caseworm by passing rope on crop and draining water 12. Release egg parasitoid Trichogramma japonicum on 30 and 37 [th ] day after planting

against stem borer 13. Release egg parasitoid T. chilonis and bacteria Bacillus thuringiensis against leaf

folder 14. Use of Neem Seed Kernel Extract 5% (NSKE 5%) or Neem oil 2% against

Earhead bug 15. Use insecticides as need based application if pest reaches ETL

Economic Threshold Levels (Rice)

1. Thrips 25/5 passes of wet palm

2. Stem borer 10% Dead heart or 2% white ear

3. Gall midge 10% Silver shoot

4. Leaf folder 10% leaf damage (at vegetative stage)

5% leaf damage (at Bootleaf stage)

5. GLH 5/hill at vegetative stage, 10/hill flowering stage, 2/hill in

RTV endemic areas

6. BPH (Brown

Plant Hopper)

1/tiller; 2/tiller when spider present at 1/hill

7. Earhead bug 5 bugs/100 panicle - Flowering stage 16 bugs/100 panicle - Milky stage

IPM for Cotton

1. Selection and use of resistant/tolerant varieties against major pests
2. Use of light trap to monitor hoppers, bollworms, cutworm
3. Use of pheromone traps for monitoring/mass trapping bollworms
4. Collection and destruction of infested plant parts, squares and bolls
5. Growing trap crop (e.g.) Castor for Spodoptera litura
6. Manual collection and removal of egg masses of S. litura
7. Hand picking of bollworm larvae
8. Use of insect viruses SlNPV and HaNPV against Spodoptera litura and

Helicoverpa armigera respectively 9. Avoid ratoon and double cotton crop 10. Avoid staking of stalks in the field 11. Synchromise sowing time at village level 12. Follow crop rotation with unrelated crops 13. Removal of alternate hosts 14. Judicious use of nitrogen and water to manage hoppers and white flies 15. Use of yellow sticky traps for whiteflies 16. Observe IRM (Insecticide Resistance Management) practices like

a. Treat seeds with Imidacloprid 7.5 g/kg seed of cotton to manage early stage

sucking pests b. Use of predators like Chrysoperla carnea

c. Use of egg parasitoid Trichogramma sp. against bollworms 17. Apply insecticides only based on need, when pest population/damage reaches ETL

Economic Threshold Levels (Cotton)

1. Leaf hopper/thrips: 50 nos./50 leaves (or 1/leaf)
2. Whitefly: 5 nymphs/leaf
3. Bollworms: 10% damage of reproductive parts
4. Stem weevil: 10% infested plants
5. Spodoptera litura: 8 egg masses/100 m row

Summary Cheat Sheet

• Rice IPM combines agronomic practices, water management, resistant varieties, and biological control against pests like BPH, stem borer, and leaf folder.
• Cotton IPM uses trap crops, manual removal, pheromone traps, predators, parasitoids, and need-based insecticide use.
• Economic threshold levels are central to both rice and cotton IPM because they guide action before losses become uneconomic.
• Neem formulations, parasitoid release, and field sanitation are recurring non-chemical tools in practical crop IPM.
• This lesson is important for exam questions linking pest monitoring with crop-specific decision-making.