Search for, and Development of, Nematode Resistance in Grape Rootstocks

This year we have focused our attention on obtaining a broader genetic base for resistance to virulent pathotypes of root-knot (Meloidogynespp.) and dagger nematodes (Xiphinema index),broadening our search for resistance to ring nematode (Mesocriconema xenoplax) and to sources of resistance to pin nematode (Paratylenchus sp.). We have invested considerable effort into developing sterile dual-culture techniques which will allow us to understand the mechanisms of resistance provided by various genetic sources. We continue with our efforts to develop culture techniques for Xiphinema americanum and in monitoring the performance of resistant rootstocks in field trials. We continue to expand and to improve accessibility to the database for plant resistance to nematodes and for selection of rotation and cover crops. Further we have disseminated results of our research to end users and in scientific media.