Development of a laboratory bioassay to test flight responses to semiochemicals in the western flower thrips, Frankliniella occidentalis
Dublon IAN, Hamilton JGC, Kirk WDJ
School of Life Sciences, Keele University, Staffordshire ST5 5BG, UK.
Correspondence: i.a.n.dublon@keele.ac.uk
Frankliniella occidentalis (Pergande) is an established horticultural pest with a ubiquitous distribution. Its thigmotropic behaviour makes it difficult to control with insecticides and resistance is present in many strains. Two compounds, (R)-lavandulyl acetate and neryl (S)-2-methylbutanoate, isolated from the head-space of male F. occidentalis have been identified recently (Hamilton et al. 2005) and evidence thus far suggests that one of these compounds could be used for monitoring or mass trapping. The behavioral effects of these components on female and male F. occidentalis need to be investigated further in a laboratory environment. Y-tube bioassays only allow for the observation of a limited walking response. Alternative bioassays are therefore required to examine other responses, such as flight. Currently there are very few ways of bioassaying the flight response of thrips to specific semiochemicals within a laboratory without using a full-scale wind tunnel. Data are presented for the results of bioassays of the flight responses of adult female F. occidentalis to geraniol (trans-3,7-dimethyl-2,6-octadien-1-ol) using a novel twin-chamber moving-air bioassay. This compound is known to attract F. occidentalis in flight. It is hoped to use this working assay with the male-produced compounds. (Hamilton JGC. et al. 2005. Journal of Chemical Ecology 31: 1369¨C1379)
