Response of Different Strains of the Green Peach Aphid to Malathion

Abstract

Several strains of the green peach aphid (Myzus persicae (Sulz.)), reproducing only parthenogenetically, showed some differences in the amounts of malathion required to kill them. Aphids from Nebraska, Illinois, and Maryland were initially much less tolerant to malathion than aphids from California or Washington. Aphids bred from those surviving treatment showed some increase in tolerance over the original strains, but continued selection did not give further increases. Aphids with wing pads withstood malathion applications better than aphids without wing pads.