抄録
Traps baited with male Leptoglossus australis (FABRICIUS) captured its egg parasitoid, Gryon pennsylvanicum (ASHMEAD), along with host adults. G. pennsylvanicum showed high parasitization of host eggs artificially set in a cucurbit plot where L. australis occurred but lower parasitization in eggs placed away from the plot. However, parasitization increased when caged L. australis males were placed next to the eggs. This indicates that G. pennsylvanicum uses chemicals originating from the host male as a kairomone in its host-searching process. A sign of the presence of the host male may help the parasitoid find host eggs- L. australis males attract conspecific females, which lay their eggs o host plants in the neighboring area, with a pheromone. The chemicals functioning as a kairomone for the parasitoid may be the pheromone of L. australis males, although experiments using a synthetic pheromone should be done for confirmation.
