Abstract
Food choice trials with the slug pests Arion lusitanicus and Deroceras reticulatum were carried out in the laboratory, using seedlings of rape, Brassica napus and several weed species. The attraction of the weeds to the slugs was compared with rape and, subsequently, the potential of the presence of weeds to reduce slug feeding on young rape was assessed. Capsella bursa-pastoris and Taraxacum officinale (only for A. lusitanicus) were very attractive weeds and rape was not significantly more defoliated than C. bursa-pastoris and T. officinale when tested with these two weed species. Moreover Veronica persica (A. lusitanicus) and C. bursa-pastoris (D. reticulatum) reduced the number of killed rape plants significantly. Therefore these weeds, sown in high quantities into fields of oilseed rape, could potentially prevent young rape plants from severe slug damage.