Effect of Andrographolide on ovarian development of Papilio demoleus L. (Lepidoptera: Papilionidae) larvae
Srinivasa Rao Vattikonda, Madhavi M, Sabita Raja S
Andrographolide is the main bioactive component of Andrographis paniculata it is diterpenoid and bitter substance which is extracted from the stem and leaves of the Andrographis paniculata. andrographolide exhibits a broad range of biological activitie. It is an insect growth regulator, we observed the effect of different concentrations (2, 4, 6, 8 and 10 μg / μl doses) of Andrographolide on the reproductive system of the Papilio demoleus, in our observations various morphological abnormalities like deformation and degeneration were observed in the ovaries and accessory glands of sterile insects. Histological investigation of the ovaries in infertile insects indicated a degeneration of ovarian follicle cells, defective vitellogenesis. Comparative anatomical and histological studies of the treated and untreated ovarioles revealed that there was inhibition in the development of ovarioles. The untreated Papilio demoleus showed normal ovarioles with large amount of yolk in the oocytes localized in the vitellarium portion. However Andrographolide affected ovarioles showed disrupted structures of the germarium and vitellarium with either complete or partial damage of few or all oocytes. untreated ovarioles revealed accumulation of large amount of yolk in the oocytes whereas in case of Andrographolide treated ovarioles, the yolk was markedly reduced and acquired several vacuoles indicating the resorption of the yolk or reduction in its synthesis. The results demonstrated that Andrographolide causes rapid cessation of oviposition due to disruption of ovarian structure and inhibition of oocyte growth following topical treatment on 4th 5th instar and pupae of Papilio demoleus.