Adopt invariably crop rotation Crop rotation with other crops like Jowar, dry Paddy, Variga, Korra, Bajra, Soybean, Black gram, Gingelly reduce the incidence of Whitefly and American boll worm. By rotating cotton with the above mentioned crops also increase the number of predators and parasites which helps in controlling number of pests on cotton. Select resistant varieties as per the situation In case of severe Jassid infestation areas select varieties like L-604, LRA 5166, L-603, Savitha, Narasimha (NA 1375), NHH 44, H 8, NHH 390 and Lam Hybrid. In case of Whitefly areas select varieties like LK 861, LPS 141 (Kanchana) and NA 1280. Treatment of seed before sowing Treat the seeds with conc. Sulphuric acid @ 100 ml/kg seed for 2-3 minutes and wash thoroughly in flowing water and with lime water, dry in the shade for removal of fuzz. The seed then treat with Carbosulphan (40 g/kg seed) or Imidachloprid (5 g/kg seed) will protect the crop from sucking pest for 3-4 weeks. After 3-4 weeks apply to soil at optimum moisture level Carbofuran granules (15 kg/acre) for control of Bollworms and also save the parasites and predators which are enemies to different crop pests. Intercropping in cotton Growing Greengram, Blackgram, Cowpea, Groundnut and Setaria will not only reduce the incidence of pests but also give additional income from intercrops. Other Practices Use pheromone traps (4 traps/acre) for knowing intensity and identification as well as to trap the male moths. Setting of light traps (one light trap/5 acres) to know the range of pest incidence as well as to kill moth population. Arrange bird perches (10/acre). Use of Biopesticides like Neem oil (5%), Neem Kernel extract (5 kg/acre). Add sticky materials to spray mixtures for effective adherence of chemical to the plant part and longevity of the effect of pesticide. The build up of broad spectrum predators-spiders, coccinellids and chrysopids should be synchronised with other cultural operations. Release of Trichogramma egg parasite @ 50,000/ha and Chrysopa egg Iarval .predator @ 10000/ha, should be done as soon as the first brood of boll worms is noticed. Topping of cotton plants when maximum egg laying of Helicoverpa armigera is noticed (October-November months) . Application of Helio NPV @ 500 LE/ha or BT formulation @ 1 I/ha or Neem seed kernel extract (5%) in synchrony with early larvae of Helicoverpa. Neem oil formulation to manage whitefly initially. Sowing of trap crops like Castor, Mary-gold, Bhendi, etc. Deep ploughing at least once in 2-3 years. Use of organic manure along with fertilizers. Pick the young larva of tobacco caterpillar before they start spreading. Strong and very effective pesticide should be used only when the insect population is very high on the crop. Don't use the same pesticide repeatedly. Pyrethroids can be used only once or twice if the pest could not be controlled by any other pesticides. Chemical Control Resorting to chemical insecticides -Monocrotophos / Phosphomidon / Methyl Demeton if jassid attack is dominating; Triazophos /Endosulfan / Profenophos/ Neem 74 oil / Ethion if whitefly is predominant; Endosulfan / Quinalphos / Chlorpyriphos / Acephate/ Fenvalerate / Cypermethrin / Triazophos if overlapping populations of Helicoverpa are present. Spraying of certain insecticides like Endosulfan / chlorpyriphos with synergists like sesamum oil on need basis is highly effective. For managing red spider mites, application of water soluble sulphur or Dicofol must be done. Similarly if mealy bugs spread in patches to alarming level, Methyl parathion or Quinolphos may be used by mixing with Sandovit or Teepol. Removal of cotton stubbles after last picking without opting to ratoon crop or prolonging the crop duration with irrigations and fertilizer application. This is essential to break the cycles .of problem pests in the system as a whole. Farmer's Friends Egg Parasites of Borers And Defoliators There are dark coloured tiny insects feeding on the eggs of boll worm complex. They are found in all the cotton environments. The female wasp lays 20-40 eggs into the host egg and kills the later by feeding on its egg contents. Finally, they emerge as free living adults. Development from egg to adult stage takes 10 - 14 days. Eg: Trichogramma, Telenomus, Tetrastichus. Egg and Larval Parasites Dark coloured wasps lay eggs on the caterpillars feeding on the cotton bolls. They are found in all the cotton ecosytems. The young ones feed on the caterpillars eventually killing it. When ready to pupate the wasp larvae leave the dead caterpillar to spin a cocoon nearby. Wasps live for 4-7 days. Eg: Chelonus, Costesia (Apanteles), Bracon, Campoletis. Nuclear Polyhedrosis Virus The insect larvae become infected by eating virus contaminated foliage. The larva becomes inactive and stops feeding. Later, the larva turns whitish and then black and hangs upside down. The oozing fluid from the dead larvae contaminates the foliage and in turn other healthy larvae feeding on the crop. Predators The green lace wing female lays 300-400 stalked eggs singly or in cluster. Eggs turn pale to whitish and then black before hatching. The life cycle is completed in 19-24 days. The males live for 10-12 days and female upto 35 days. They feed on aphids, white files, mealy bugs and eggs and early instar larvae of boll worms. Management strategy for pink boll worm in cotton The first brood during cotton season develops mainly on buds and flowers. In infested squares, before flower opening, the larva spins a web around the tips of the petals and prevents flower opening (rosette flowers) and thereby protects itself from hot sun and natural enemies. Larvae feed upon developing anthers and style and occasionally on the ovary. Attacked small buds shed while larger buds develop with poor quality kapas. Since eggs are mostly protected by calyx and the newly hatched larvae bore into the bolls immediately, it is difficult to manage this pest with insecticides. Therefore, hygienic methods are more important than chemical control. These are : Avoid staggered sowing in an area and take up timely sowings. Use acid delinted seed only. Keep the crop free from weeds. Monitor the pest build up with field scouting and pheromone traps. Destroy pink boll worm larvae in rosette flowers and also through periodical removal of dropped squares, dried flowers and pre-matured bolls, to suppress pest population in the initial stage. Avoid ratooning or summer cotton. Allow cattle, sheep and goats to graze upon immature green bolls and attacked bolls after final picking to prevent carry-over of the pest to the next season. Promptly remove and destroy cotton stubbles to prevent carry over of pest to next season. Restrict the movement of cotton seed from other areas / states. Need based use of insecticides. Seed fumigation with methyl bromide at 0.4 kg/1000 cu ft/phostoxin 50 tablets / 1000 cu ft for 24 hours. Ginning mills to burn the stained kapas regularly.

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