COMMON CABBAGE RESISTANCE MECHANISMS AGAINST THE DIAMONDBACK MOTH - STILL AN OPEN-BOOK

Despite the extensive research on host plant resistance of Brassica ol eracea L. var. capitata (common cabbage) against Plutella xylostella L . (diamondback moth), knowledge of the resistance mechanisms involved remains incomplete. While robust evidence exists for the physical (ant ixenosis) mechanisms believed to cause resistance in glossy-leaved bre eding lines, the one mechanism proposed in the literature to date (pol ar leaf extracts causing antibiosis) at best only explains a part of t he resistance observed in two partially-resistant normal-bloom breedin g lines in the field and the evidence is suggestive rather than direct . Evidence from other host plant resistance studies involving P. xylos tella is discussed and the other possible mechanisms are considered wi th the aim of providing a context for further investigations on host p lant resistance mechanisms against P. xylostella.