EMBRYOGENESIS IN ANASTREPHA-FRATERCULUS (DIPTERA, TEPHRITIDAE)

Anastrepha fraterculus (Diptera: Tephritidae) is a pest infesting nume rous plant species. Although it oviposits in the earlier stages of app le growth, the embryo does not develop there but the host fruit falls to the soil causing great damage to apple production in the Sough of B razil. Today the control efforts are directed to the adult stage but t he results are not efficient. So, an understanding of this fly's ontog enetic cycle may permit the development of methods of biological pest management. In the present study, the embryogenesis of A. fraterculus was analyzed under Petrolatum oil and compared with that of D. melanog aster. Changes in outer morphology were used and seventeen stages were described. Timing was not the most reliable method of staging because the embryonic period lasted approximately 72 hours at 25 degrees C wh ich made it difficult to analyze an embryo from the start to the end o f development. Moreover, after the ninth stage there is a great superp osition of different developmental stages suggesting that the egg-larv a developmental rate may be under polygenic control. The median embryo viability found was 71.65% when the adult flies were best-fed and 59. 4% when they were middle-fed; these results suggest that nutritional s tatus of ovipositing females can affect developmental pattern.