Effects of deploying ethanol lures in tandem with generic pheromone lures for attraction of cerambycid beetles in field bioassays

Abstract

Abstract Male cerambycid beetles of the large subfamilies Cerambycinae and Lamiinae produce aggregation-sex pheromones that attract both sexes. The pheromones of many species are conserved among both closely related species (e.g., congeners) and more distantly related species (e.g., different subfamilies), including those endemic to different continents. This parsimony in pheromone structures suggests that multiple species may be attracted to traps baited with blends of pheromones, and such blends are finding use in delineating geographic ranges of native species and in surveillance programs for incursions of exotic species. Here, we present the results of a field experiment conducted at multiple sites in Iowa that tested the effects of deploying ethanol lures in tandem with a 6-component blend of common pheromone components for cerambycine and lamiine species and a 5-component blend that specifically targeted lamiines. Eight cerambycine species showed significant treatment effects, most of which were attracted to the 6-component blend, and ethanol increased attraction for half of these species. Two cerambycine species were attracted only by ethanol. Seven lamiine species were attracted by the lamiine-specific blend, alone or when combined with ethanol, and 3 of these species also were attracted to the 6-component blend. Taken together, these findings provide further evidence that carefully crafted blends of pheromones can be used to monitor the presence or abundance of multiple cerambycid species. Ethanol either increased the number of beetles attracted by pheromones or had no effect, so there is no apparent downside to deploying ethanol lures in combination with pheromones.