Classical biological control of Drosophila suzukii in Italy

In the last decade, the invasive fruit fly Drosophila suzukii (Matsumura) has become a major pest to the soft-skinned fruit production worldwide. Current integrated pest management exploits different control tools, including conservative or augmentative biocontrol, but relies mainly on insecticides. Classical biological control (CBC) is an approach that is expected to reduce long-term management costs of D. suzukii and to increase economic and environmental sustainability of farms. In 2021, following foreign explorations, quarantine risk assessment and release approval, a voluntary partnership of researchers from several Italian regions/provinces set up a three-year CBC program using a Japanese G1- lineage population of the larval endoparasitoid Ganaspis brasiliensis (Ihering). Three years after the initial release of G. brasiliensis, we discuss the results obtained and the constraints encountered throughout the different work stages, from the importation procedure of the biocontrol agent to its mass-rearing, up to the large sampling effort undertaken to characterize the biocontrol activity and the non-target impact of the released G. brasiliensis.