Kairomonal Effect of Certain Organic Acids on the Egg Parasitoid, Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae)

Chemical signals play an important role in communication between different organisms determining the ecological balance between host plants, insect pests and their natural enemies. Some organic acids present in host insects and plants influence host habitat location and host location by insect natural enemies. Kairomonal response of Trichogramma chilonis Ishii to seven organic acids, viz., triacontanoic, docosanoic, octocosanoic, tricosanoic, pentadecanoic, heptacosanoic and hexacosanoic acids, was studied by laboratory bioassay. Among the acids tested, triacontanoic acid elicited the highest response from T. chilonis , followed by docosanoic and octocosanoic acids. Triacantonic acid at 10 ppm concentration and docosanoic acid at 20 ppm concentration could be used successfully in IPM programmes for enhancing the activity of T. chilonis in different agroecosystems.