Chemosterilization of Larvae and Adults of the Egyptian Cotton Leafworm, Prodenia litura, by Apholate, Metepa, and Tepa

Abstract

Three chemosterilants, apholate, metepa, and tepa, were evaluated on the Egyptian cotton leafworm, P. Utura F., by larval and adult treatments. The 3 compounds were equally toxic to 4th-instar larvae and caused only partial sterility of the emerged adults even at doages high enough to cause 50-70% mortality. The sterilizing effect was manifested as lowering in egg production as well as egg viability. Adult feeding of either sex on sugar solutions of the chemosterilants resulted in 100% sterility with the sublethal concentrations of 1.1% metepa, 1.2% apholate, or 0.08% tepa. Thus tepa was approximately 14X and 15X as effective as metepa and apholate, respectively, in its sterilizing effect. Feeding any of the 3 chemosterilants to male moths resulted in lowering of number of eggs as well as the percent viability of the eggs laid by the females with which they mated.