Regulierung der Weißen Fliege im Kohlanbau durch den kombinierten Einsatz von Kulturschutznetzen und Nützlingen - Erste Ergebnisse des BÖL-Projekts

The cabbage whitefly, Aleyrodes proletella, has gradually developed into a key pest, affecting the quality of organic Brassica vegetables. Netting may provide partial control of the cabbage whitefly. In the ongoing project mechanical control methods using the barrier effect of netting and biological control methods with naturally occurring whitefly antagonists, namely the predatory ladybeetle Clitostethus arcuatus and the larval parasitoid Encarsia tricolor, are combined and their efficiency tested in small-scale field experiments. During the first year, adverse weather conditions affected the study. However, first results indicate, that even under relatively low host densities the parasitation by E. tricolor was enhanced after their release inside the nets, in comparison to corresponding controls with nets only. C. arcuatus adults were recovered up to 60 days after their release, although progeny was not observed throughout the vegetation period. Application of netting reduced whitefly larvae and puparia by more than 70%.