Characterizing brown marmorated stink bug, Halyomorpha halys Stal (Hemiptera: Pentatomidae), host plant usage and acceptability: methodological strengths and shortcomings

Authors: HADDEN, WHITNEY - Syngenta Crop Protection; Hepler, James; BEERS, ELIZABETH - Washington State University; Cooper, William - Rodney; Leskey, Tracy; BERGH, J. CHRISTOPHER - Virginia Tech

Submitted to: Entomologia Experimentalis et Applicata
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary: We compared various tools for assessing the invasive brown marmorated stink bug host plant usage. First, we attempted to use baited traps deployed in a number of wild host trees to measure overall populations present in tree canopies, but found that presence of a pheromone lure in traps resulted in statistically equal captures and no meaningful differences among host trees. We then evaluated host usage by tagging adults and nymphs, and tracking their retention on wild host tree and cultivated fruit tree hosts using a harmonic radar system. In this case, we did observe differences, with peach trees and baited apple trees (positive control) providing longer retention times and indicating these were more acceptable hosts. We then assessed gut contents of adult bugs using molecular tools to identify host plants they had fed on; here, we identified a number of hosts that adults had fed upon but no measure of actual overall acceptability. Combining harmonic radar with molecular tools such as gut content analysis will provide a more thorough assessment of host use patterns of this invasive pest.

Technical Abstract: We assessed brown marmorated stink bug, Halyomorpha halys (Stål), seasonal patterns of host use and/or preference using three diverse approaches. We compared H. halys captures in small pyramid traps baited with H. halys aggregation pheromone and deployed in the mid-canopy of individual host trees during discrete intervals over two seasons. While captures were greatest in the late season, there was no significant effect of host tree species on captures, with the presence of pheromone lures likely confounding results. Harmonic radar was used to measure retention duration of tagged H. halys on potted trees including Ailanthus altissima, Robinia pseudoacacia, Celtis occidentalis, Morus rubra, Prunus persica, and Malus domestica, as a proxy for host acceptability. Season-long, adults were retained significantly longer on P. persica and pheromone-baited M. domestica (positive control) compared with non-host grass treatment (negative control). For nymphs, significantly longer retention was recorded on nearly all hosts compared with non-host grass treatment. We also evaluated results of molecular gut content analysis of adults collected in the early and late season. Plant DNA from 22 genera across 18 families was detected. Commonly detected early season hosts included Betula, Diospyros, Juglans, Liriodendron, Prunus, Rubus, and Sisymbrium and late season hosts included Ailanthus, Chenopodium, Juglans, Persicaria, and Prunus. Overall, harmonic radar provided context for seasonal changes in host acceptability, and gut content results provided confirmation of specific host usage at different points in the season. Combining these two methods could provide a more comprehensive approach for defining host use patterns of this polyphagous pest.