Effect of Chemosterilants on Fertility of Cabbage Loopers

Abstract

Experiments conducted from 1961 to 63 at Riverside, Calif., to determine the effects of apholate, tepa, and metepa on reproduction of the cabbage looper, Trichoplusia ni (Hübncr), showed that male moths feeding on apholatc and tepa were sterilized by lower dosages than females. Males were sterilized when fed 0.06% apholate or 0.02% tcpa solutions whereas 0.25% apholate or 1% tepa was necessary to induce complete sterility in females. Neither chemical appeared to affect male longevity. Male moths exposed for 2 hr on residues from aqueous solutions of 4%, 8%, or 16% tcpa were completely sterilized, but residues from aqueous solutions of 16% or 32% metepa were necessary to produce the same effects. Male moths were sterilized after 15 min or longer on glass surfaces treated with 8% tepa. Exposure to 18-day-old residues from 8% tepa also produced complete sterility. Residues up to 38 days of age continued to produce a high degree of sterility.