LAUSR

Abstract Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) and brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), are global economic pests that may co-occur on small fruits. We investigated whether fruit recently exposed to H. halys affected subsequent host use by D. suzukii. Laboratory no-choice and choice tests presented D. suzukii with H. halys-fed and unfed raspberries and blueberries immediately or 3 d after H. halys feeding. Resulting D. suzukii eggs, or larvae and pupae, were counted. The number of D. suzukii immatures among fed and unfed fruit was not significantly different in lab studies. There was no relationship between the intensity of H. halys feeding, as estimated by the number of stylet sheaths, and D. suzukii oviposition on blueberry. Lastly, field studies compared D. suzukii infestation between H. halys-fed and unfed raspberries. Raspberries were previously exposed to H. halys for 3 d or simultaneously exposed to both pests for 7 d. Natural infestation by D. suzukii in the field was similar among raspberries previously or simultaneously exposed to H. halys compared to control fruit.