Exploring Saccharomycopsis vini as a novel parasitoid-friendly attractant for efficient attract-and-kill of Drosophila suzukii (Diptera: Drosophilidae).

Effective management of the fruit pest Drosophila suzukii Matsumura (Diptera: Drosophilidae) requires new strategies to reduce insecticide use and minimize their negative impact on beneficial organisms. This study evaluated the effectiveness of Saccharomycopsis vini supernatant, a formulation that retains attractive cues while offering improved storage and handling conditions compared to the non-sterile yeast suspension. In recent years, yeast-based attract-and-kill approaches have shown strong potential, with Hanseniaspora uvarum widely studied as an attractant. However, little attention has been given to alternative yeast species and the use of yeast supernatants rather than live cultures. In this study, we assessed for the first time the attractiveness of S. vini supernatant alongside H. uvarum suspension. In a Y-maze olfactometer bioassay, both formulations were attractive to D. suzukii females. Field trials in a vineyard and cherry orchards confirmed the efficacy of both yeast formulations when combined with spinosad. Importantly, the D. suzukii parasitoid Ganaspis kimorum Buffington (Hymenoptera: Figitidae) did not show increased mortality relative to spinosad alone. In conclusion, S. vini supernatant proved to be as effective as H. uvarum suspension in attracting D. suzukii, while showing no increase in parasitoid mortality compared with spinosad alone under laboratory conditions. These results highlight S. vini as a promising component of yeast-based attract-and-kill strategies and provide a solid basis for developing selective and sustainable management tools for D. suzukii.