Stable isotope labelling of the Mediterranean fruit fly Ceratitis capitata (Diptera: Tephritidae)

The use of stable isotopes to label an insect species, the Mediterranean fruit fly Ceratitis capitata (Diptera: Tephidae) (medfly) was investigated. Labelling allows mating and life history characteristics to be investigated experimentally. 13C6-glucose was incorporated into the diet of medflies at various stages of development by adding it to larval media or providing adults with sugar water. Data was collected from egg hatching until the death of adults. The results show that stable isotopes successfully labelled medflies in laboratory conditions. There were significant differences between labelled and unlabelled treatments in terms of eggs hatching rates, larval development, pupae emergence, adult survival, and mating behaviour. Labelling during larval development, and combined labelling at the larval and adult stages, resulted in detectable values. Labelling in the larval stage had no effect on mating behaviour, but that in the adult stage did. This study demonstrates that it is possible to label adult medflies and to detect the label after mating