Influence of Host Plants on Insecticide Metabolism and Management of Variegated Cutworm12

Abstract

Midgut microsomal aldrin epoxidase of Peridroma saucia (Hübner), when fed peppermint leaves Mentha piperita L., was up to 9 times more active than larvae that were fed leaves of other host plants, such as, alfalfa, Medicago sativa L., bush snap beans, Phaseolus vulgaris L., garden beets, Beta vulgaris L., or a weed host, curly dock, Rumex crispus L. Epoxidase levels in larvae fed peppermint leaves were ca. 6 times more active than those fed a semidefined artificial diet. Larvae collected from peppermint fields had higher levels of the enzyme than laboratory-reared cutworms, and activity was much higher in instars 5-6 than in instar 4. Larvae fed peppermint leaves were more tolerant of acephate, methomyl, and malathion than larvae fed bush snap bean leaves.