Abstract
Topical application of thiotepa on the adult male spruce budworm, Choristoneura fumiferana Clemens, at a concentration of 10 μg/insect resulted in 100% sterility. Unlike metepa, thiotepa did not have any apparent adverse effects on the competency of the sperms. Large numbers of male moths can be sterilized by allowing them to walk for 30 min on filter paper treated with a 2.5% solution of thiotepa in a 3:1 mixture of acetone and diffusion pump oil.