Semiochemical investigations of the insidious flower bug, Orius insidiosus (Say)

Females of the insidious flower bug, Orius insidiosus (Say) (Hemiptera: Heteroptera: Anthocoridae), produce a volatile sex pheromone and a non-volatile trail pheromone. The sex pheromone consists of the female-specific compound, (E)-2,7-octadienal, and a compound emitted by both sexes, (E)-2-octenal. A synthetic blend of octadienal and octenal weakly, but significantly, attracted O. insidiosus males to sticky traps in the field. The trail pheromone is somehow deposited by O. insidiosus females on the substrate as they walk, and, once contacted, stimulates conspecific adults to search in the vicinity. O. insidiosus males most likely respond to the trail pheromone as the ultimate means to locate potential mates, whereas the benefit of females responding to the trail pheromone may be that this signal acts as a cue indicating the likelihood of finding nearby prey. The O. insidiosus trail pheromone compounds were not identified. The volatile and non-volatile pheromones of O. insidiosus, along with prior research demonstrating that Orius and other anthocorids frequently exploit prey-associated odors as kairomones that guide their foraging, highlight the extent to which the minute pirate bugs use chemical communication. The semiochemistry of the Anthocoridae, particularly their reliance on non-volatile pheromones and kairomones, reinforces the emerging realization that other terrestrial heteropterans also substantially communicate via contact chemoreception, although this communicative channel has not been thoroughly investigated.