THE INFLUENCE OF ADULT DIET AND AGE ON LIPID RESERVES IN THE TROPICALFRUIT-FLY ANASTREPHA-SERPENTINA (DIPTERA, TEPHRITIDAE)

We investigated the effect of diet [dry sucrose (S); dry sucrose + pro tein (S+P); dry sucrose + open fruit (S+OF); dry sucrose + intact frui t (S+IF); open fruit (OF); and intact fruit(IF)] upon the lipid reserv es, onset of oviposition, lifetime egg production and longevity of adu lt female and male Anastrepha serpentina (Diptera: Tephritidae), Starv ed flies died at a high rate after the third day of adult life, Lipid reserves in starved flies dropped drastically during the first days of adult life, Egg production and survival were highest in flies maintai ned on a diet of S+P, followed by flies maintained on diets of OF and S+OF. Longevity and egg production were lower in flies kept on diets o f S and S+IF than on the other diets. Flies kept on IF did not produce eggs, and longevity was similar to that of starved flies, Lipid reser ves were similar in both sexes fed the same diet, Lipid reserves of fl ies kept on S+P decreased during the first days of adult life but afte rwards were replenished. Lipid reserves in flies kept. on diets of S+O F, OF and S+IF oscillated: short periods of utilization were followed by periods of reloading, Flies kept on S and IF alone showed a continu ous utilization of reserves without replenishment, Rate of utilization was faster for flies on IF than on S. The link between the variation in nutrient requirements and metabolic processes with possible consequ ent variations in foraging activity is discussed.