Efficacy of novel insecticides against shoot and fruit borers, Earias spp. in okra

Abstract

Among various insect pests attacking okra, shoot and fruit borers, viz., Earias vittella and E. insulana are highly significant, causing substantial losses to the crop. For effective management of these pests, it is crucial to evaluate insecticides with innovative mode of action. In this context, present study was conducted for two consecutive years to evaluate the efficacy of some novel insecticides viz., chlorantraniliprole 18.5% SC, emamectin benzoate 5% SG and pyridalyl 10% EC against Earias spp in comparison to traditional ones such as λ-cyhalothrin 5% EC, cypermethrin 25% EC and quinalphos 25% EC. All the insecticides were applied to okra crop thrice at recommended doses of 25, 6.75, 50, 15, 37, and 200 g a.i. ha^− 1, respectively, and observations on infestation (shoot and fruit) and yield of okra fruits were recorded. Results revealed that novel insecticides were more effective than old ones. Chlorantraniliprole exhibiting significant reduction in shoot and fruit infestation and maximum increase in yield of marketable okra fruits was most effective against Earias spp. followed by emamectin benzoate and pyridalyl. In contrast, λ-cyhalothrin, cypermethrin and quinalphos were less effective and more or less on a par with each other. Incremental cost benefit ratio was however, highest in treatment involving emamectin benzoate followed by λ-cyhalothrin and chlorantraniliprole while minimum in treatment involving pyridalyl. Thus, chlorantraniliprole and emamectin benzoate can be used alternatively for the efficient management of Earias spp. in okra.