Evaluation of a SWD trapping system utilizing a controlled-release formulation of a quinary blend from apple cider vinegar

Drosophila suzukii Matsumura, commonly referred to as spotted wing drosophila (SWD), is a significant pest of soft-skinned fruits and causes significant economic loss for growers. Currently, management solutions rely on insecticides to provide adequate control of this pest. Most SWD monitoring systems available for use have failed to meet grower expectations. Development of a convenient, efficient, and more selective system is needed to allow growers to make informed and timely management decisions. Utilizing five components identified as SWD attractants from apple cider vinegar (ACV), previous trapping tests found that this quinary blend of components improved selectivity over the standard apple cider vinegar and the commercially available lures. In this study, the quinary blend was formulated into polyethylene dispenser sachets to control its release rate. These "controlled-release" sachets were placed into two different types of traps: dry traps utilizing a sticky substance as the trapping material and liquid traps utilizing a drowning solution to trap SWD. The trapping systems were deployed in a Maryland blueberry field and nearby wooded area in 2018 and 2019 to test for SWD trapping efficiency, selectivity, and date of first capture. Release rates for the "controlled-release" sachets were also tested within the laboratory. "Controlled-release " sachet trapping systems were found to have improved selectivity and captured SWD earlier than the standard ACV trapping system. With the relative ease of deployment and processing of the dry trap system the quinary blend "controlled-release" sachet dry trap system has the potential to improve SWD monitoring in commercial settings.