Attract-and-kill for managing Popillia japonica (Coleoptera: Scarabaeidae) abundance and leaf injury in commercial vineyards

Abstract

Popillia japonica Newman (Coleoptera: Scarabaeidae) feeding negatively impacts many plant species, including grapes, potentially reducing fruit quality and yield. Chemical control, representing the current grower standard, relies on frequent broadcast applications of broad-spectrum insecticides, with alternative management strategies mostly lacking. Attract-and-kill (A&K) is a behavioral management strategy that combines semiochemical attractants and a killing agent on a substrate. This study assessed the impact of A&K on (i) the number of P. japonica adults and (ii) the percent of P. japonica feeding injury on grape foliage compared to the grower standard in commercial vineyards. This 2-year study was conducted at 3 commercial vineyards with 4 paired plots consisting of a grower standard control and an A&K treatment. The A&K treatment consisted of commercial lures, each placed on outside-edge grapevines, and weekly applications of carbaryl on the plants holding lures. The grower standard received broadcast insecticide applications at the grower's discretion. The A&K treatment experienced similar numbers of P. japonica adults and similar proportions of leaf injury compared to the grower standard. The use of A&K reduced by 96% the crop area treated with insecticides compared to the grower standard. The area treated by A&K was at the edge of the vineyards, where more leaf injury occurred regardless of treatment. A&K is a targeted approach that was effective at managing P. japonica and reducing chemical inputs on a small scale. It has the potential to be scaled up and refined to provide growers with a new management strategy.

Keywords: Japanese beetle; behavioral management; foliar injury; grape; integrated pest management.