Evaluation of Attractants for Monitoring Drosophila suzukii (Diptera: Drosophilidae).

Drosophila suzukii Matsumura is an economically important pest of soft and small fruit crops. Unlike other drosophilid flies, D. suzukii is capable of infesting ripe and partially ripe fruit, which poses a significant pest management challenge, as there is no tolerance for infested or damaged fruit in the marketplace. As a result, producers in many regions rely on calendar-scheduled insecticide applications for D. suzukii management. In order to develop an integrated pest management approach, better tools for monitoring adult fly populations are needed. Over two growing seasons in southern Ontario, we evaluated three commercial (Pherocon SWD dual-lure, Suzukii Trap, and Scentry Lure) and two homemade baits (apple cider vinegar and yeast + sugar water) for their ability to capture D. suzukii in raspberry and highbush blueberry fields. In general, commercial attractants captured D. suzukii earlier in the growing season and in greater numbers, with fewer nontarget captures, compared with homemade baits. Scentry Lure tended to perform better than other attractants, capturing D. suzukii earlier and in larger numbers during peak harvest. Pherocon SWD dual-lure was highly specific to D. suzukii. The combination of Scentry Lure with Suzukii Trap had possible synergistic effects, as numbers of D. suzukii captured to the combined treatment were more than additive. Using commercial attractants improves D. suzukii monitoring and will allow growers to improve the timing of insecticide applications with D. suzukii activity in the field.