Stink lover: A predator uses a common stink bug volatile to find an invasive host pest

The brown marmorated stink bug (BMSB), Halyomorpha halys, is an invasive pest of vegetable and fruit crops in North America. Generalist insect predators utilize BMSB as prey; however, the chemical cues used by these natural enemies in host location are largely unknown. I tested the hypothesis that tridecane, a BMSB-associated volatile, acts as a kaironome for Orius insidiosus during prey location. Experiments were conducted in 2014 at two experimental research facilities, Rutgers University, New Jersey. In the laboratory, a four-arm olfactometer was used to record the behavioral response of O. insidiosus males and females to tridecane (0.02, 0.2 and 2 µL). In the greenhouse, I assessed the effect of tridecane on O. insidiosus attraction and egg predation in cages. In the field, I tested whether Orius spp. is attracted to tridecane-baited traps in peach, blueberry, and sunflower fields and its effect on egg predation. Traps and sentinel eggs were placed near dispensers containing either 1, 2, or 3 mL of tridecane; 3 or 5 ml of methyl salicylate (a plant volatile); or nothing. In the olfactometer, O. insidiosus males were attracted and arrested by tridecane. In the greenhouse, O. insidiosus was attracted to plants baited with tridecane, but egg predation was not affected. In the field, Orius spp. were also more attracted to tridecane-baited traps; however, this attraction did not lead to greater egg predation. In conclusion, although O. insidiosus is attracted to tridecane, this attraction did not lead to higher egg predation likely because this kairomone acts as an arrestant.