Chemical Sterilization of Honey Bee Spermatozoa in vitro

Abstract

INSECT chemosterilants can act either by attacking the gamete (direct action) or by interfering with the tissues or nutrients that support the gamete (indirect action)¹. It is hard to tell whether the chemosterilant acts directly or indirectly when the developing gamete is under the nutritional and regulatory control of the parent organism. But because adult male insects usually have a full complement of mature spermatozoa immediately after eclosion, only a directly acting chemosterilant should be effective for adult males. The male organism would then serve only as a receptacle for the interaction between the sperm and the chemical. When Herskowitz² used vaginal douches to insert a mutagen into inseminated female Drosophila, he obtained the first indication of mutagenic effects of a chemical on sperm outside the male organism. Because honey bees, Apis mellifera L., can be successfully fertilized by artificial insemination, we could test the direct action hypothesis by treating bee semen in vitro with the chemosterilant tris(l-aziridmyl)phosphine oxide (tepa) and determining the effect of the treated semen on the reproduction of the queen bees.