RESUMO
Experiments were conducted on Ceratitis capitata larvae and adults to determine the influence of sugar (glucose and sucrose) ingestion on some aspects of the feeding behavior of this species. The results indicate that larval choice of a diet containing glucose or sucrose is not influenced by the rearing diet, by carbohydrate deprivation or by previous experience (induction). Carbohydrate deprivation did not alter the discrimination threshold of the larvae for sucrose. In adult females, the discrimination threshold for sucrose was unchanged when the flies were submitted to carbohydrate deprivation during the adult phase although ingestion by deprived females was 35% higher than ingestion by the control group. However, adults submitted to carbohydrate deprivation during the larval phase suffered a profound reduction in discrimination threshold for sucrose.
RESUMO
In a previous study we demonstrated that Ceratitis capitata larvae show a superior performance when they feed on the apical portion of papaya compared to larvae that feed on the basal portion, probably due to the higher levels of sugars in the apical portion. In the present study we carried out experiments to determine if larval feeding on the basal or apical portion of the fruit influences ovarian development and egg production by adult C. capitata females. The results indicate that females that feed on the apical portion during the larval stage have more developed ovaries and produce more eggs than females who feed on the basal portion during the larval stage. We also compared artificial diets of quantitatively similar chemical composition to the apical and basal portions of the papaya fruit. In this last experiment, no differences were detected in any of the parameters studied, i.e. percent emergence, time to pupation, adult size, larval preference, ovary size, egg production and estimated ingestion.
