New grape rootstocks from the University of California
Five new rootstocks from Andy Walker's breeding program at UC-Davis (cleverly named GRN-1 through 5):
New nematode resistant rootstocks for 2008 (Western Farm Press)
I was particularly pleased to see that GRN-1 is a hybrid of bunch grape and muscadine. Despite lots of talk about Euvitis/Muscadinia hybrids, there really haven't been many releases (I can only think of this and 'Southern Home', as well as maybe a few germplasm releases).
I don't know nearly as much about grape rootstock breeding as I do about the above ground part, but I always enjoy seeing how much wild material is used, and the completely different selection of species they're dealing with: V. champinii, rufotomentosa, monticola, rotundifolia, rupestris, and berlandieri, just in these five releases. Some of these (especially the first three) rarely if ever occur in the pedigrees of fruiting vines.