1985 Fall Armyworm Symposium: Chemical Control: Host Plant Induction of Microsomal Monooxygenases in Relation to Organophosphate Activation in Fall Armyworm Larvae

Abstract

Various host plants were found to induce microsomal monooxygenase activity that activates organophosphorus insecticides in larvae of the fall armyworm, Spodoptera frugiperda (J. E. Smith). Of these plants, cotton and parsley were best inducers of microsomal organophosphate desulfuration and sulfoxidation, respectively. The induction was associated with increased toxicity of numerous phosphorothionate and thioether-containing insecticides. Analyses of internal insecticide revealed that, at various intervals, induced larvae retained less phorate and its oxidative metabolites than did the controls, indicating that induction caused an overall increase in the rate of insecticide metabolism in this insect.