Factors affecting the implementation of exclusion netting to control Drosophila suzukii on primocane raspberry

Authors: STOCKTON, DARA - Cornell University; HESLER, STEPHEN - Cornell University; WALLINGFORD, ANNA - University Of New Hampshire; Leskey, Tracy; MCDERMOTT, LAURA - Cornell University; ELSON, JOHANNA - North Carolina State University; RIGGS, DALE - The Berry Patch; PRITTS, MARVIN - Cornell University; LOEB, GREGORY - Cornell University

Submitted to: Crop Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/18/2020
Publication Date: 4/29/2020
Citation: Stockton, D.G., Hesler, S.P., Wallingford, A.K., Leskey, T.C., Mcdermott, L., Elson, J.E., Riggs, D.M., Pritts, M., Loeb, G.M. 2020. Factors affecting the implementation of exclusion netting to control Drosophila suzukii on primocane raspberry. Crop Protection. https://doi.org/10.1016/j.cropro.2020.105191.
DOI: https://doi.org/10.1016/j.cropro.2020.105191

Interpretive Summary: Spotted wing drosophila (SWD) is a serious invasive pest of small fruit production. Here, we investigated the utility of exclusion netting along or in combination with baited attracticidal spheres to protect raspberries and blueberries. Netting alone appeared effective against SWD in the early and mid-season, but was less effective in the late season when SWD are most numerous. Netting did provide improved horticultural attributes to developing fruit but also reduced pollination. Our data suggest that while exclusion netting may be a valuable tool for SWD pest management, supplemental pollination may be required. While our data do not strongly support the adoption of a baited attracticidal approach under netting, alternative approaches such as insecticide impregnated netting alone or in combination with unbaited spheres should be investigated to manage late-season outbreak infestations.

Technical Abstract: Sustainable management of invasive arthropod pests requires insecticide-alternative, integrative control strategies such as protected culture. During 2013-2018, we studied the use of exclusion netting as a method of reducing fruit damage by an invasive small fruit pest, Drosophila suzukii Matsumura. Small-plot experimental trials were conducted in raspberries and blueberries at three locations in New York State. We compared two types of netting for preventing D. suzukii infestation and the efficacy of attracticidal spheres at reducing outbreak infestation within netted zones. Our trials suggested that while 80g netting was sufficient to deter D. suzukii infestation early in the season, late-season infestation was often greater in netted zones compared insecticide-treated open plots. The introduction of baited attracticidal spheres under the netting did not consistently reduce infestation and may increase infestation risk in some situations likely due to the presence of the bait. We also monitored the effects of netting on abiotic conditions near the fruiting zone, as well as pollination effects due to exclusion. Although temperature and humidity between netted and un-netted plots, fruit grown under netting did suffer pollination deficits. However, netting appeared to improve overall fruit marketability, as average berry weight and the incidence of other damage was reduced in netted zones. These data suggest that while exclusion netting may be a valuable tool for D. suzukii pest management, supplemental pollination may be required. While our data do not strongly support the adoption of a baited attracticidal approach under netting, alternative approaches such as insecticide impregnated netting alone or in combination with unbaited spheres should be investigated to manage late-season outbreak infestations.