E;ffect of gamma radiation Oil Tribolium castaneum (Herbst) and Tribolium co11fusum Duval

Abstract

The radiosensitivity of 7: casta11eum and 7: COT!fusum was determined with particular reference to male sterilisation. The younger stages were found to be more radisensitive than the older ones in both the species. Adults, male and female, showed the most radioresistance followed by the pupae> larvae> eggs as indicated by higher LD50 values. T casta11e1m1 was more radioresistant throughout ontogeny compared to T cm?(us11111. The longevity studies showed that, mean survival time and dose rate were highly position correlated in both the species. They also showed that males were longer-lived than females ~n both the species. There was very little difference in L TSO at dose levels of 1-to 3-krad for both the sexes. The radiosensivity indices decreased as the both species. Studies evaluating mating performance with normal and irradiated individuals reveled that the fecundity was gradually suppressed with increased gamma doses irradiated either as pupae or adults for both 7i'ibolium species. The results ol' the reproductive potential showed that the maxi111u111 eggs per day per female was recorded for the cross schedule Uo'X U~ compared to crosses involving the irradiated individual for both the species and stages. Results show that, the lowest number eggs were observed in the cross schedules To'X T? for both the species irradiated either pupae or adults. These results clearly indicate that egg-hatchability in · li'ibo/ium species was adversely affected by irradiating males and females. The present findings reveal that the patterns of hatchability followed the dose-dependent manner. It also indicates that the hatching was completely inhibited at a dose level of 3 krad.-------