Avoiding unwanted vicinity effects with attract-and-kill tactics for harlequin bug, Murgantia histrionica (Hahn)

Authors: WALLINGFORD, ANNA - Virginia Polytechnic Institution & State University; KUHAR, THOMAS - Virginia Polytechnic Institution & State University; Weber, Donald

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/1/2018
Publication Date: 4/18/2018
Citation: Wallingford, A.K., Kuhar, T.P., Weber, D.C. 2018. Avoiding unwanted vicinity effects with attract-and-kill tactics for harlequin bug, Murgantia histrionica (Hahn). Journal of Economic Entomology. https://doi.org/10.1093/jee/toy109.
DOI: https://doi.org/10.1093/jee/toy109

Interpretive Summary: The harlequin bug is a serious stink bug pest of brassica crops, and new tools are needed for vegetable growers to manage this pest with reduced or no pesticide inputs. Attract-and-kill approaches integrate behavioral and chemical controls to divert pest insects away from crops by attracting them to a source of toxin. Harlequin bug males produce an aggregation pheromone, murgantiol, which is attractive to both sexes of the adults, as well as the nymphs (young). A commercial murgantiol lure is available, so development of an attract-and-kill approach is a viable option for farmers. This approach may lead to control of the pest, while reducing pesticide use or avoiding application of pesticides to the crop entirely, conspicuous pest damage is often concentrated in the areas around traps. This project investigated potential methods of mitigating these proximate effects which lead to increased crop damage in crop plants neighboring highly attractive lures. We evaluated the influence of murgantiol in combination with host plants to attract and arrest HB on traps. We compared the influence of neonicotinoid treated host plant and long-lasting insecticidal netting incorporated with pyrethroid to retain arrested HB and mitigate proximate effects. The results of this research will be useful in developing traps or behavioral controls to manage this serious pest, and will be of interest to pest managers and researchers developing environmentally-friendly methods to manage vegetable pests.

Technical Abstract: In the development of an attract-and-kill approach for the management of harlequin bug (HB), Murgantia histrionica (Hahn), we evaluated attraction and retention of HB by pheromone-baited traps in the field. In release-recapture and on-farm experiments, traps combining collard plants with commercial lures containing HB aggregation pheromone (mixed murgantiols = 10,11-epoxy-1-bisabolen-3-ol) captured more HB than traps with either plant or lure alone. In order to avoid proximate effects, increased feeding injury to neighboring crop plants due to halo or spillover effects, we also investigated two methods of retaining HB that were attracted to traps: a systemic neonicotinoid applied to the trap plant as a drench, and long lasting insecticidal netting (LLIN) with incorporated deltamethrin surrounding trap plants. More HB adults and more HB feeding damage was observed on collard plants neighboring lures only, compared to those neighboring lures in combination with a poisoned plants, which indicates that improvements to retention acted to mitigate spillover effects. We also conducted laboratory assays in order to estimate the length of exposure to LLIN necessary to knock down HB adults and nymphs, calculating a knock down time (KDT50) of 78.3, 2.6, and 2.1 s for females, males, and nymphs, respectively.