Effect of rootstock on the production, grape and wine quality of shiraz vines in the Murrumbidgee irrigation
The grape production and grape and wine quality of Shiraz vines, grown either on their own roots or on 6 rootstocks that have varying resistance to nematodes, were compared. Vines on the rootstocks Ramsey and Dog Ridge out-yielded ungrafted vines by 46 and 4S0/o, respectively, principally because of increased vegetative growth and hence retention of more nodes at pruning. Ramsey rootstock gave a greater grape yield per shoot. The ability of Dog Ridge stocks to produce yields as high as those of Ramsey highlights the importance of adequate pruning levels to enable the full potential of rootstocks to be determined. Vines on the rootstock Dog Ridge produced wines with higher pH values than wines from ungrafted control vines. Nematode counts suggested that the Vitus champini stocks have good tolerance to both rootknot and root lesion nematodes.