Olfactory responses of Drosophila suzukii to host plant volatiles

Drosophila suzukii is a highly polyphagous invasive pest endemic to South East Asia, which has recently invaded western countries. Its serrated ovipositor allows this fly to lay eggs on and damage unwounded ripening fruits, and for this reason it is considered a main threat to fruit production. D. suzukii presence in Europe is spreading rapidly and has now been reported in nine countries. The development of environmentally-safe control methods is urgent for a safeguard of the concerned fruit industry. The aim of this study was therefore to characterize and identify the volatiles of the D. suzukii host plants which influence its olfactory behaviour in order to set-up management strategies based on semiochemicals. The olfactory responses of the adult flies for the odour released by intact host fruits in behavioural assays have been evaluated. It was shown that D. suzukii females are attracted to the volatiles emitted from the tested fruits. Volatile compounds emitted by the attractive host fruits have been extracted and identified (GC-MS), and their biological activity on D. suzukii females screened by means of electrophysiological analysis (GC-EAD)