Rearing and gamma radiation effects on mature pupae of pink bollworm and their F1 progeny

Pink bollworm larvae were successfully reared in captivity on a casein wheat germ diet. The substitution of casein with soyflour, corn-cob grit and wheat germ, and casein for peanut flour, resulted in delayed development, reduced pupal recovery and fecundity of the adult moths. This reduction was more drastic in corn-cob grit and peanut flour diets. The irradiation of mature pupae at 50-200 Gy resulted in decreased adult emergence with increased gamma radiation doses, and more deformed moths were recorded at a dose of 200 Gy. Adults following irradiation of mature pupae when crossed with untreated males or females or treated individuals crossed to treated exhibited reduced fecundity and fertility with the increasing doses. This reduction was more pronounced when treated males were crossed with treated females. Females were relatively more sensitive to gamma radiation, as a reduced number of eggs was obtained when treated females were crossed with untreated males. At 200 Gy, no F1 progeny were obtained from any cross involving treated parents. The fecundity and fertility were reduced significantly when F1 males or F1 females from male parents irradiated as mature pupae were mated with untreated insects at both 100 and 150 Gy. However, inherited sterility was more pronounced when F1 males were crossed with untreated females than when F1 females were crossed with untreated males. Similarly reduced fecundity and fertility in F1 progeny from female parents irradiated as mature pupae, both at 100 and 150 Gy, were also recorded in crosses as described for male F1 progeny. The fecundity and fertility were the lowest in F1 progeny of both male and female parents irradiated as mature pupae when compared with the F1 progeny of male or female irradiated parents separately. (author). 28 refs, 7 tabs