Submitted to: Acta Horticulturae
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/18/2012
Publication Date: 11/22/2013
Citation: Knight, A.L., Yee, W.L., Hilton, R. 2013. Developing a new bait for spotted wing Drosophila in organic cherry production. Acta Horticulturae. 1001:147-152. Interpretive Summary: Spotted wing drosophila is a new pest in North America that attacks a large number of fruit crops including cherry. Researchers at the USDA, ARS, Yakima Agricultural Research Laboratory,Wapato, WA in collaboration with researchers at Oregon State University tested the use of adding a cane sugar plus bread yeast bait to an organic insecticide to improve control of this pest in cherry orchards. The major finding of this study was that adding this inexpensive bait to the organic insecticide significantly increased the speed of kill of the flies and reduced levels of fruit injury.
Technical Abstract: Studies conducted at the USDA Laboratory in Wapato, WA and at Oregon State University were initiated in 2011 to improve the efficacy of an organically-certified formulation of the insecticide spinosad (Entrust®) for control of the spotted wing drosophila, Drosophila suzukii. Our initial approach was to evaluate the possible benefits of adding a bait composed of brown sugar and compressed bread yeast, Saccharomyces cerevisae. Direct comparisons with the protein-based baits, GF-120® and Nu-Lure® in laboratory tests showed that this sugar-yeast bait was more effective than either commercial product. We found that fly mortality at 2 and 6 h was significantly increased throughout the season with the addition of the bait. In particular, the addition of the bait with Entrust increased fly mortality 4-fold in early-season bioassays with green and yellow cherries. While the mean numbers of eggs laid and larval infestations of cherry was reduced (50%) with the addition of the sugar-yeast bait, these differences were not significant. Studies are continuing in 2012 with a new yeast candidate that is an effective biofungicide and with a higher concentration of sugar that may be an effective repellent of birds. The potential of this bait to improve control of the western cherry fruit fly, Rhagoletis indifferens is also being evaluated.