First insights into the chemical ecology of an invasive pest: Olfactory preferences of the viburnum leaf beetle Pyrrhalta viburni

Authors: DESURMONT, GAYLORD - European Biological Control Laboratory (EBCL); MORELON, STEPHANIE - Neuchatel University - Switzerland; BENREY, BETTY - Neuchatel University - Switzerland

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/11/2020
Publication Date: 2/6/2020
Citation: Desurmont, G.A., Morelon, S.P., Benrey, B. 2020. First insights into the chemical ecology of an invasive pest: Olfactory preferences of the viburnum leaf beetle Pyrrhalta viburni. Environmental Entomology. 49(2):364-369. https://doi.org/10.1093/ee/nvaa007.
DOI: https://doi.org/10.1093/ee/nvaa007

Interpretive Summary: The viburnum leaf beetle is an emerging invasive landscape pest in North America. It attacks native Viburnum shrubs, defoliating them and killing them after a few years of infestation. Little is known about how viburnum leaf beetle detects its host plants in the field. Here we investigated the preferences of adults of the viburnum leaf beetle for the odors of two of its host plants, Viburnum opulus nd V. lantana. We found that beetles are attracted by odors of their host plants, particularly odors ofr freshly attacked V. opulus twigs. These results could be used to develop baiting traps that would be highly useful in the monitoring and management of this invasive pest.

Technical Abstract: The viburnum leaf beetle (VLB), Pyrrhalta viburni (Paykull), is an invasive chrysomelid in North America where it infests native Viburnum shrubs in woody areas and managed landscapes. Despite its invasive and destructive nature, little is known about the chemical ecology of this beetle, and efficient chemical lures for monitoring and trapping this insect have yet to be developed. Using two of the main host plants of VLB in its native range, Viburnum opulus and V. lantana, we examined the olfactory preferences of VLB under laboratory conditions and measured volatile emissions of Viburnum twigs with and without VLB damage. VLB females had a clear preference for V. opulus and V. lantana twigs compared to blank odor sources. In addition, twigs with foliar damage and fresh egg masses were found to be more attractive than non-infested twigs when VLB infestation was recent, but not when twigs had been infested for several weeks. Chemical analyses revealed consistent treatment-specific blends of compounds, which may be used for the elaboration of attractive lures. Future research should focus on the identification of these compounds and on exploring the olfactory preferences of VLB with Viburnum species present in North America.