Behavioural Responses of the Solitary Endoparasitoid Cotesia vestalis (Haliday) to Damaged Cabbage

Cotesia vestalis (Haliday) is the key biological control agent of Plutella xylostella L, the diamond back moth. This study investigated the influence of induced chemical defenses in cabbage (Brassica oleracea)on the olfactory responses of C. vestalis females. Herbivores trigger plants to release more volatile organic compounds (VOCs), attracting natural enemies. This study hypothesized that C. vestalis would be more attracted to specific volatiles emitted from differently herbivore-damaged cabbage compared to undamaged plants. Y-olfactometer experiments revealed that C. vestalis females were significantly more attracted to volatiles emitted by P. xylostella-damaged cabbage. This preference was also observed for plants damaged by Crocidolomia spp. Gas chromatography analysis confirmed qualitative and quantitative differences in volatile profiles between damaged and undamaged cabbage. Findings suggest that induced plant volatiles play a critical role in attracting C. vestalis to host plants, highlighting the potential for using plant-mediated attraction to enhance biological control strategies.