Exploring Matrine and Oxymatrine as Potential Bioinsecticide to Control Drosophila suzukii (Diptera: Drosophilidae)

A bottleneck in sustainable fruit production is the replacement of chemical products with natural compounds. Matrine and oxymatrine, derived from a Chinese medicinal herb, have exhibited potential for controlling agricultural pests. However, there is no information regarding their effectiveness in managing dipterans. Thus, we carried out experiments to evaluate the effect of the botanical compounds matrine and oxymatrine on Drosophila suzukii (Matsumura) adults under laboratory conditions. First, we tested four doses of the commercial product matrine, with distilled water as a control treatment. Each treatment was offered as a droplet, to five D. suzukii couples in screened cages. Adult mortality was evaluated at intervals of 12, 24, 36, 48, 60, and 72 h post-exposure. All doses tested of the commercial matrine-based product caused up to 58% of mortality in D. suzukii adults. Second, the consumption of pure extract of oxymatrine was evaluated using a CAFE assay. Three D. suzukii females were exposed to oxymatrine concentrations of 0.05, 1.0, 2.5, 5.0, and 7.0% in a 20% sugar solution for 24 h. Afterwards, the flies were deprived of food for 40 h, and mortality was evaluated. The pure extract of oxymatrine induced mortality in D. suzukii females only at doses of 2.5, 5.0, and 7.0%. These botanical compounds demonstrate the potential to be used to control D. suzukii adults and can be explored as one tool of the Integrated Management Program.