Cytochrome P-450-dependent monooxygenase activity in the velvetbean caterpillar, Anticarsia gemmatalis Hübner

The activity of microsomal aldrin epoxidase was observed in various tissues of the last instar larva of the velvetbean caterpillar (Anticarsia gemmatalis Hübner) with the midgut being the most active. Optimum conditions for assaying the enzyme were established. Allelochemicals (monoterpenes, indoles and flavones) and host plants (cowpeas, cotton, peanuts, soybeans and hairy indigo) were found to induce the monooxygenase. Piperonyl butoxide decreased and increased the toxicity of methomyl and methyl parathion, respectively, suggesting that the monooxygenase system of velvetbean caterpillars plays a major role in the detoxification of xenobiotics.