Effect of ultraviolet radiation UV at the first generation (F1) of the lesser grain borer beetle Rhyzopertha dominica (Fab.) (Coleoptera: Bostrichidae)


The study was applied to show the effective of ultraviolet radiation UV in the first generation (F1) of the lesser grain borer beetle Rhyzopertha dominica (Fab.) (Coleoptera: Bostrichidae) which resulted from adults mating that was radiated at stage of pupae at ages (5-6) days and with a length wave 312 nm with different durations times(30,35,40 minutes) , according to style of mating. The results showed that decreasing of number of eggs which females laid and ratio of hatching for both radiated males and females with increasing duration of radiation. We found average of eggs that was laid (19.33 eggs/ female) when mating radiated males and females at pupae stage and it exposed for a period 40 minutes. Otherwise it was the ratio non hatching was (47.88%) and we find that ratio at same style of mating . We noticed decreasing of average of eggs laid and the ratio non hatching eggs at the mating of irradiated males with radiated females in comparison with mating radiated males and irradiated females , we found that case in all duration times of radiation. After that the pupae and larvae increased their the ratio of mortality that resulted from mating radiated males with irradiated females and we found the highest average was (23.63%) for larvae , at the period of exposed for radiation 40 minutes and for the pupae was (12.82%) at the period of radiated periods 35 minutes. When irradiated males mated with radiated females , there was the highest number average of mortality , and its average was 22.82% for larvae and for the pupae it was 11.82% at the period 30 minutes. Finally the ratio of emergence for adults was decreased in all styles of mating treatment in comparison with control. And it was the least average of emergence was 8.60% in the case of mating radiated males and females at 40 minutes.