Electroantennogram and Behavioural Response of Chrysoperla carnea (Stephens) to the Volatile Compounds of Brassica

Abstract

Thirty volatile compounds were identified in the extracts of Brassica species (Brassica napus, B. nigra, B. rapa, B. juncea and B. carinata). Quantitative and qualitative differences were found among the volatiles extracted from uninfested plant, aphid infested plant and prey. This study aimed to evaluate the effects of extracted volatile compounds on the electroantennogram (EAG) and behavioral responses of the predator Chrysoperla carnea. Twenty four hosts related synthetic compounds belonging different groups (hydrocarbons, organic volatile compounds) were also tested for same effect against both insects. In EAG studies, both male and female of Chrysoperla carnea was found more sensitive to volatiles of aphid infested plant than uninfested plant and prey. The same treatments were also compared for their attractiveness in multi-arm olfactometer. Among the treatments tested, volatiles aphid infested plant attracted maximum number of predators. The per cent attraction responses of C. Carnea to the volatiles compounds of host plant and aphids were significantly higher over control (Fisher’s LSD, p < 0.05). The implication of these findings was discussed in contest of their ecological and biological significance.