Laboratory food choice trials to explore the potential of common weeds to reduce slug feeding an oilseed rape

Food choice trials with the slug pests Arion lusitanicus and Deroceras reti culatum were carried out in the laboratory, using seedlings of rape, Brassi ca 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-pa storis and Taraxacum officinale (only for A. lusitanicus) were very attract ive weeds and rape was not significantly more defoliated than C. bursa-past oris and T. officinale when tested with these two weed species. Moreover Ve ronica persica (A. lusitanicus) and C, bursa-pastoris (D, reticulatum) redu ced the number of killed rape plants significantly. Therefore these weeds, sown in high quantities into fields of oilseed rape, could potentially prev ent young rape plants from severe slug damage.