Published online by Cambridge University Press: 31 May 2012
Laboratory studies were conducted with the carrot rust fly, Psila rosae (Fabricius), to determine the effect of irradiation on reproduction. Irradiation of 15-day-old pupae with 1.4, 2.8 and 4.3 kiloroentgens did not adversely affect emergence. Treated females caged with normal males laid a few sterile eggs when the treatment was 1.4 kr. but none at the higher doses. Normal females caged with treated males laid a normal complement of eggs, and the per cent hatch was 10, 2 and 0 with treatments of 1.4, 2.8 and 4.3 kr., respectively. When flies of both sexes from pupae treated at 3.0 kr. were mixed with normal flies in a ratio of 6:1, the number of larvae were reduced by 93%.