Effects of precocene and methoprene application in young adult Musca autumnalis

Abstract Observations were made on the relative rates of growth among corpora allata, ovarian follicles and fat bodies in diapausing and reproductive Musca autumnalis DeGeer. Rates of corpora allata growth were greater in long‐day than in short‐day animals. Topically applied precocene II reduced the size of the corpora allata. Two sequential doses of precocene inhibited vitellogenesis. Topically applied methoprene produced vitellogenesis in short‐day flies and inhibited development of hypertrophied fat body. This work provides evidence that Juvenile Hormone is the primary agent controlling diapause and non‐diapause (vitellogenic) development in the ovaries of face flies.