Effect of Gamma Irradiation on Sex Pheromone Gland and Reproduction of Female Cotton Leaf Worm Spodoptera littoralis (Boisd.)

Female pupae of the cotton leaf worm were gamma irradiated at different ages with different doses to study the histology of the female sex pheromone gland in normal and irradiated produced moths. Reproduction of adult produced from irradiated full grown pupae was also investigated. The gland of normal female moth is found in the ninth abdominal segment, which is usually invaginated in the 8 th segment. It is formed of enlarged glandular epithelial cells under the cuticle. These epithelial cells are deeply invaginated in side the body cavity to form paired pouches and a sac-like structure. From each glandular cell there grows one long hair. in females emerging from 3 day-old pupae irradiated with 60 Gy, the glandular epithelial cells, became loose and were separated from each other, their nuclei were not clear. The pouches were randomly distributed. Gamma radiation effects were also noticed in case of 6 day-old pupae irradiated with 120 Gy. In addition, the glandular epithelial cells lost their peculiar shape, with the appearance of some vacuoles between them. When full grown pupae were irradiated with 200 or 350 Gy the glands of emerged adult showed increasing vacuoles, cytoplasm deterioration and more destruction of pouches. Irradiating full-grown female pupae with 200 and 350 Gy decreased significantly the fecundity and egg hatch ability of the emerging adult females. The effect was dose dependent and the dose of 350 Gy almost prevented egg hatching