Piercing and sucking mouth parts sensilla of irradiated mosquito, Culex pipiens (Diptera: Culicidae) with gamma radiation.

Morphology, distribution and function of the sensilla associated with mouthparts of female mosquito, Culex pipiens (Diptera: Culicidae) were studied by using the scanning electron microscope. The female mosquito mouthpart is a piercing and sucking type and carrying many sensory organs which plays major role in host seeking, and oviposition behaviour of mosquitoes. Six types of mouthpart sensilla have been identified and described, Sensilla trichoidea, chaetica, basiconica, Capitate peg, campaniformia and squamiformia. Females mosquito were irradiated as pupae with 20, 40 and 80 Gy of gamma radiation to investigate their effect on mouthparts sensilla. Dose of 20 Gy had slight effect on the different types of the sensilla as compared with the control. Features of malformation observed in the maxillary palp segments at this radiation dose include falling of some scales (sensilla squamiformia) at certain parts of the 1st segment leaving vacuoles. At 40 Gy, the maxillary palp segments were liquefied in some areas leaving undistinguished shape. At the highest dose 80 Gy, the tip of labial palps had many tears and showed were most affected, especially, at the trichoid, basiconic and chateica sensilla. All these malformations may lead the mosquitoes to not reaching the host, impeding their ability to transmit diseases or killing the mosquitoes, and this is the main objective of this study.

Impact of substerilizing dose on histological changes in gonads and ovaries of Ephestia cautella (Lepidoptera: Pyralidae) by gamma radiation.

To investigate the effect of Gamma radiation on the reproductive systems of emerged female and male of Ephestia cautella (Walker) moths, mature pupae of both sexes were irradiated with doses of 50, 100 and 150 Gy. Histological study of the treated individuals showed in females that the ovaries appear sever damage in the follicular epithelium at all doses, which become thinness and separated from developing oocytes, moreover, some of the nurse cells were rupture. In males which treated with 150 Gy, it was noticed retardation in the stages of spermatogenesis and few numbers of sperm bundles and their dispersion in the testicular follicles' adults, on the other hand, the doses of 50 and 100 Gy showed little or moderate effects on the structure of the testis contents.