| Abstract: | Orientation to host plant and host insect volatiles in the coccidophagous coccinellid, Chilocorus nigritus (F.) was examined using a four-arm olfactometer. Experienced adult females were attracted towards the combination of Solanum tuberosum L. and Abgrallaspis cyanophylli (Sign.) odours, walked further and spent longer in their presence, and showed an increased turning rate and net speed than in their absence. Host plant volatiles increased speed but decreased turning rates compared with odourless controls, but elicited no strongly directional response. It is postulated that this beetle and other coccinellids have a hierarchical prey-location mechanism which involves host habitat location based on olfactory responses. |
