Canadian Journal of Zoology (2015) 93, 281-287

A. Tamiru, T.J.A. Bruce, C.M. Woodcock, M.A. Birkett, C.A.O. Midega, J.A. Pickett and Z.R. Khan (2015)
Chemical cues modulating electrophysiological and behavioural responses in the parasitic wasp Cotesia sesamiae
Canadian Journal of Zoology 93 (4), 281-287
Abstract: A better understanding of the chemical cues employed by parasitoids to locate their herbivore hosts will contribute towards effective exploitation of parasitoids as biological control agents against damaging crop pests. The current study was conducted to establish key bioactive compounds mediating behavioural response in the parasitic wasp Cotesia sesamiae (Cameron, 1906) (Hymenoptera: Braconidae) by employing electrophysiological techniques and behavioural studies. Electroantennogram (EAG) recording with synthetic equivalents of herbivore-induced plant volatiles (HIPVs) using C. sesamiae confirmed that 13 compounds elicited electrophysiological activity. In an olfactometer bioassay, only (E)-4,8-dimethyl-1,3,7-nonatriene, (E)-ß-farnesene, and (E,E)-4,8,-trimethyl-1,3,7-tridecatetraene elicited behavioural responses from the parasitoid when tested individually at a natural dose, while (R)-linalool and (E)-caryophyllene were attractive at the highest test dose. Other EAG-active HIPVs were not attractive either at lower or higher concentrations, suggesting their role as blend components rather than functioning as attractants by themselves. In contrast, nine-component synthetic HIPV blends formulated in the same ratio and concentration as in a natural sample was as attractive as the original headspace sample. By providing further insights into maize–stemborer–parasitoid tritrophic interactions, results from this study will help in selecting crop cultivars emitting appropriate HIPVs to attract natural enemies and perhaps repel damaging crop pests.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Amanuel Tamiru, Toby J.A. Bruce, Michael A. Birkett, John A. Pickett, Zeyaur R. Khan, Charles A.O. Midega

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Cotesia sesamiae (parasitoid)