Microwaves Induce Histological Alteration of Ovaries and Testis in Rhynchophorus ferrugineus Oliv. (Coleoptera: Curculionidae)

The Red Palm Weevil (RPW) is one of the major pests of palms, frequently leading to the plants death. Action plans and the development of bio/physical strategies to contrast RPW diffusions are strongly recommended due to the serious concerns related to environmental pollution and insects' resistance to chemicals. In the present study, we investigated morphological alterations of the ovaries and testes in adult RPW exposed to 2.45 GHz for 5, 15, and 30 s. During these treatments, the relative increase in temperature and the days of survival after irradiation were monitored. Then, RPWs were processed for macroscopical and microscopical analysis. Histological lesions of the ovaries and testes were characterized by the degeneration and necrosis of germinal cells, which increased with the increase in the time of irradiation and the temperature. By the same token, an increase in the temperature of irradiated insects was associated with a decrease in their survival time. These observations lead us to conclude that MWs could represent a useful tool for reducing or eliminating the reproductive capacity of this dreaded insect.