Abstract
Pupae of Anopheles pharoensis Theobald were subjected to various doses of gamma rays from Cobalt-60, i.e., 10,000–13,000 röntgen with 1,000 röntgen increments to study their effects on lifetime egg production, egg hatchability, and longevity of adult mosquitoes and to find the exact dose of gamma rays which may cause complete male sterility. The sterilizing dose (12,000 röntgen) was used to investigate its adverse effects on pupae of different ages and the dose fractionation on the emerged adults. The results indicate clearly the adverse effects of high doses of gamma radiation on all characters studied except longevity of adult mosquitoes. A dose of 12,000 röntgen caused complete sterility in both sexes. The results suggest that it was better to give the whole amount of the sterilization dosage at once rather than in fraction when pupae aged 15-20 hours were used.