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Abstract : |
Considering the role of phenolics in plant defense, some cotton varieties were investigated for their total phenols at various growth stages, change in phenolics as a result of insect exposure and their effect on growth and survival of cotton boll worm larva. More resistant variety Ravi showed 1.00 to 1.20 mg more phenolics than susceptible varieties at all growth stages. A direct correlation was observed between insect attack and phenol production. Bollworm diet incorporated with tannic acid and phenolic mixture at 0.1% concentration showed phagodeterrency, 61 to 96% weight retardation, 44 to 50% mortality in 1st week of experiment and 94 to 100% mortality in 2nd week of experiment. Phenols showed 5.05% pupation (delayed) while no pupation in tannic acid treatment. Methanolic extract of Ravi showed more effect on bollworm larvae than susceptible variety S-12., |
