Evaluation of Different Insecticide Mixtures Against Third Instar Larvae of Helicoverpa armigera (Hübner)

The descending order of toxicity of insecticide mixtures together with LC₅₀ values in parentheses was ducord (0.1013) > virat (0.1190) > anaconda (0.1373) > nurelle D (0.1435). po1ytrin C (0.2213) > nagata (0.2240) > spark (0.2455):> koranda (0.3523). The time of observation had little impact on the mortality and suggested observation could be taken at 24 hrs after treatment. Thus use of insecticide mixtures having either cypermethrin or alphamethrin with chlorpyriphos or quina1phos as their components could be best utilized to avoid or delay the development of resistance and control of the pest under field conditions.