In tritrophic ‘plants-herbivores-natural enemies’ systems, there are relatively few reports concerning the role(s) of kairomones in pupal parasitism. Chouioia cunea Yang (Hymenoptera: Eulophidae), an endoparasitic chalcid wasp, parasitises pupae of the fall webworm (Hyphantria cunea Drury). The role of host-related kairomones was investigated using electroantennogram (EAG) and behavioural techniques. Chemicals from some host stages (pupae) and host by-products (frass), induced arrestment behaviour of female parasitoids, while chemicals from prepupae, were inactive. Gas chromatography-mass spectrometry analysis of volatiles collected from pupae, frass and pre-pupae using solid-phase microextration revealed seven compounds with carbon chain lengths ranging from C4 to C20. All of the chemicals elicited significant EAG responses in C. cunea. Y-tube olfactometer bioassays demonstrated a significant positive response of mated female C. cunea to 1-dodecene. The authors concluded that these data provide a better understanding of the host location mechanisms of pupal parasitoid. The role of host-related kairomones was investigated using electroantennogram (EAG) and behavioural techniques.
Full Source: Zhu G, Pan L, Zhao Y, Zhang X, Wang F, Yu Y, Fan W, Liu Q, Zhang S, Li M. ;Full Source: Bulletin of Entomology Research. 2016 Sep 15:1-7. [Epub ahead of print] ;