Evaluation of Toxicity of Different Pesticides to the Green lacewing, Mallada boninensis (Chrysopidae:Neuroptera)

Abstract

The green lacewing, Mallada boninensis (Okamoto) is an important predator or sucking insects like mealybugs, syrphids and psyllids. A total or 34 commercial pesticides (18 insecticides, 16 acaricides/fungicides) on the larvae and adults of M. boninensis was studied for their initial toxicity at field recommended concentrations. Larvae were less susceptible than the adults. Fenvalerate, endosulfan, methyl demeton and synthetic pyrethrolds were less toxic to tbe larvae. None or the insecticides tested was safe to the adults or M. boninensis . But the fungicides proved harmless to both the larvae and adults. The insecticides which had shown high initial toxicity were further tested for their residual toxicity to both the stages. Insecticides like dichlorvos, methyl demeton, endosulfan and synthetic pyrethrolds had low residual toxicity and hence could be incorporated into the integrated control programme.