Natural Products for the Control of Scaphoideus titanus in Vineyards: A Summary of Five-Year Field Trials

Scaphoideus titanus Ball, 1932 (Hemiptera: Cicadellidae), the main vector of the phytoplasma (FDp) causing Flavescence dorée, is considered a challenging problem in European vineyards. Natural insecticides permitted for S. titanus control in Italian organic viticulture are generally considered of low-to-moderate efficacy. Morever, it should be mentioned that their optimal use requires a careful approach when preparing the insecticide solutions. Synthetic insecticides used in Italian viticulture are included in only two IRAC groups, indicating potential risks for resistance. Therefore, there is a need to identify alternatives or control tools complementary to synthetic insecticides. In this study, we summarize the results obtained in five field experiments (2021–2025) using the main alternatives to synthetic insecticides (i.e., pyrethrins, kaolin, azadirachtin, Beauveria bassiana, and potassium salts of fatty acids). In all seasons, pre-insecticide application populations did not differ significantly among treatments, whereas differences emerged after insecticide applications. The overall results showed that pyrethrin-based insecticides were the most effective in reducing S. titanus nymph densities. Kaolin provided intermediate but comparatively stable levels of control across the years, whereas B. bassiana showed moderate yet highly variable efficacy. The findings obtained here can be considered in designing management strategies for S. titanus in organic viticulture that require an integrated approach combining pyrethrins with complementary, lower-impact tools to achieve effective and sustainable control over time. At the same time, natural insecticides can be incorporated into IPM strategies in conventional vineyards to prevent resistance.