Abstract:Microplitis mediator (Hymenoptera: Braconidae) is an indigenous parasitoid species attacking larvae of the cotton bollworm, Helicoverpa armigera, in China, and its application in biological control is promising. Knowledge of its chemical ecology is limited. Electroantennograms were recorded from female parasitoids Microplitis mediator to extracts of tobacco plants and 10 tobacco volatile compounds. The EAG responses of (1~5) days old female parasitoids to cis-3-hexen-1-ol were also tested. Their behaviora...