EFFECTS OF ANOXIA DURING GAMMA-IRRADIATION ON FACE FLY FERTILITY AND VIABILITY (DIPTERA, MUSCIDAE)

Irradiating 6-d old Musca autumnalis De Geer pupae in nitrogen with 50 0-2,500 rads did not affect adult emergence, female fecundity, or male competitiveness. Male and female fertility decreased with increased d ose, reaching about 1% at 2,500 rads. Egg to adult survival upon backc rossing irradiated males or females to unirradiated flies was only 7% at 1,500 rads and 0.7% at 2,000 rads. Doses of up to 2,000 rads did no t affect male survival, but males treated with 2,500 rads had reduced survival rates. These results are better than those with irradiation i n air and indicate that irradiation with 1,800-2,000 rads in nitrogen would maximize dominant lethality and minimize fitness loss.