The long term objective of this research is to investigate the comparative neuro-endicrine regulation of reproduction in moths. The specific aim of this proposal is to investigate the neuro-hormonal regulation of reproduction in Heliothis virescens and to test the hypothesis that endogenous juvenile hormone (JH) in virgin females declines and that a fecundity enhancing factor is derived from males enhances female fecundity in mated females. In order to test this hypothesis this project specifically focuses on the following: (1) to measure hemolymph JH titers and biosynthetic ability of corpora allata (CA) from virgin and mated females; (2) to measure levels of JH-esterase in virgin and mated females; (3) to determine if male reproductive system produces an extractable, fecundity enhancing factor; (4) to determine the ability of male CA and accessory glands to produce JH and measure JH-acid methyltransferase in these organs; (5) to determine whether JH from male reproductive system is transferred to female; (6) to determine egg development in females mated to normal males and those lacking testes, accessory glands, or the entire reproductive system; (7) to determine the role of the female's ventral nerve cord and CA in post-mating gonadotropism; and (8) to involve 2 undergraduate students in the planning, design and implementation of the various aspects of this project. This project will be implemented in close collaboration with Dr. S.B. Ramaswamy, Professor of Entomology, Mississippi State University, who will not only provide technical help but has also agreed to allow the investigator and his students the use of his laboratory facility.