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%