Releases of Trichopria drosophilae on cherry, in three locations at different altitudes in South Tyrol (northeastern Italy) and its potential to parasitize Drosophila suzukii

Abstract

In recent years, Drosophila suzukii Matsumura (Diptera: drosophilidae) caused serious damages in cherries and small fruits cultivations in South Tyrol, making it difficult for growers to continue their activities without production losses. Biological control of the pest could play an important role in its population regulation, by lowering the pest pressure at the beginning of the season. This study aims to evaluate the potential of Trichopria drosophilae Perkins (Hymenoptera: Diapriidae), an indigenous pupal parasitoid of drosophilids, in parasitizing D. suzukii in cherry orchards situated at different altitudes and characterized by different agronomic peculiarities. The release trials showed the ability of the parasitoid to find and parasitize artificially exposed pupae of D. suzukii in two out of three localities, up to 915 m. The results highlight the importance for the released species of an adequate surrounding environment for its spread and establishment.