Chemical mediation of hunting billbug (Sphenophorus venatus) host-finding and mating behavior: Implications for management in the transition zone

Hunting billbug Sphenophorus venatus damages both warm- and cool-season turfgrasses. Anecdotal evidence suggests that this species is becoming a more serious problem in areas not traditionally in its range. The objectives of this work are to (1) determine adult host preference for various warm- and cool-season grass species (2) clarify adult behavioral responses to host plant volatiles and (3) investigate the role of semiochemicals in mate-finding and recognition. Adult feeding preference was tested using a series of laboratory feeding choice assays incorporating two warm-season grasses, Bermudagrass Cynodon dactylon (var. Patriot) and zoysiagrass Zoysia japonica (var. Meyer), and two cool-season grasses, Kentucky bluegrass Poa pratensis (var. Park) and creeping bentgrass Agrostis palustris (var. Penncross). In feeding assays, S. venatus showed no clear feeding preference for warm- vs cool-season grasses, but did prefer Z. japonica over all other species. Adults were attracted to host plant volatiles (C. dactylon) in binary choice y-tube olfactometer assays. The role of volatile and contact pheromones in mating behavior will be discussed. Insight into the S. venatus host preference and chemical cues that influence foraging and mating behavior may prove useful for the development of monitoring and IPM tools for these pests.