Weevils in the Vines

Grape Days 2022 audiences heard about the one-year programme from Bragato Research Institute (BRI) Viticulture Extension and Research Manager Len Ibbotson, along with Scott Hardwick from AgResearch, and David Jordan from Vine to Wine. The scope of the project was to increase grower awareness, find out what weevil species are present in vineyards, estimate the current and future economic impact of weevil damage, and make a recommendation for next steps, says Len.

The research found that the main species present on vines in mature vineyards during the summer months appear to be garden weevil (Phlyctinus callosus), which was associated with chewing damage to leaves and bunches. “Adult garden weevil, having emerged from the soil, began appearing on vines during November to December and most of the chewing damage occurred during December and January,” he explains. The damage and incidence appears “patchily distributed within vineyards, with “hotspots” of high incidence and moderate to severe damage.

Fuller’s rose weevils (Pantomorus cervinus) were also seen in late summer and on fruit at the winery.

For more information go to nzwine.com/media/20546/bri-research-fact-sheet_weevilmonitoring.pdf