Abstract
In this paper, results of investigations on the fertility of male Bombyx mori and embryonic lethality of their progeny induced by the administration of apholate to the fifth instar larvae are reported. A pronounced reduction in fertilities was shown when doses of the chemical more than 100 μg per insect were administered at the begining of the fifth instar, whereas no reduction in their fertilities was obtained when the same treatment was applied at the middle or the end of the same instar. However, these fertilized eggs died in the process of subsequent embryonic development. The percentage of such embryonic lethality was higher when the chemical was administered at the middle or the end of the instar. Possible mechanisms behind the phenomenon of such embryonic mortality were discussed.
