Adverse effects of UV-C irradiation on the morphology of reproductive organs, fecundity, and fertility of the red flour beetle, Tribolium castaneum Herbst (Coleoptera; Tenebrionidae)

The effects of UV-C irradiation on the size of male and female reproductive organs, reproductive performance and total protein amount in reproductive organs of Tribolium castaneum Herbst (1797) resulted from 0-d-old pupae exposed to 1-to-64 min were determined. UV-C irradiation from 4 to 64 min, resulted in a reduction in size of the gonads. The degree of atrophy increased as the increase of irradiation time where long duration of radiation resulted in decreasing on the size of testicular lobe, rod-shape accessory gland, tubular accessory gland and lacking of seminal vesicle in male beetle. Radiation for more than 4 min also reduced the size of germarium, lateral oviduct and lacking oocyte in ovarioles. No egg chamber formed in UV-C radiation groups for 8, 16, 32, and 64 min. Reciprocal crosses of female adults emerging from UV-C radiated pupae for 4 min and control or UV-C radiated male showed the decreased number of eggs laid and hatching rate compared to the control. Interestingly, the sterility index was 100% when UV-C radiated male was mated with UV-C radiated female. In addition, UV-C radiation clearly reduced the total protein amount in the reproductive organs of T. castaneum which correlate with the reduction on the size of reproductive organs.