Demonstration project "Exclusion netting for managing Spotted Wing Drosophila in fruit crops” – Results 2017

The invasive Spotted Wing Drosophila Drosophila suzukii (Matsumura 1931) has become an enormous threat for European fruit cultivation. A technical possibility of control is the use of exclusion netting. In 2017, the BMEL-funded demonstration project started, including 19 producers of cherry, raspberry, blackberry and blueberry. The cherry orchards were covered with foil canopies and netted laterally. Berry cultures were equipped with foil tunnels in combination with nets or nets only. The nets had different mesh sizes varying between 0.8 x 0.8 mm and 1.3 x 1.3 mm. Due to frost damages and late infestation pressure in 2017, the examination was limited. Yet, the positive effect of exclusion netting was evident. Despite of captures of Spotted Wing Drosophila outside of the netted crops no or only limited fruit infestation occurred within the exclusion nettings. In most cases higher temperatures and lower relative humidity was measured within exclusion netting but to different extents in the course of the day. The different types of foil canopies or foil tunnels, mesh sizes, the surrounding environment, the crop management, the weather during the season and the time of day must be considered.