Rootstock Scion Interaction and Effects on Vine Vigor, Phenology, and Cold Hardiness of Interspecific Hybrid Grape Cultivars (Vitis spp.)

Scion-rootstock interactions were analyzed to test the interaction between environment and above-ground vine phenology. The experiment employed 'Marechal Foch' and 'Vidal Blanc' as reciprocally grafted, own-rooted, and self-grafted vines. Results suggest that genetically complex phenological factors were under the control of the scion cultivar. The effect of the scion on fruit composition was related to differences in yield between the cultivars. Other effects are secondary in nature as a result of vine vigor and shoot density. Factors potentially under specific root influence, (e.g., fruit-set, water status, nutrition, soil pH, salinity, or root pests) were not limiting in this experiment. © 2013 Copyright Taylor and Francis Group, LLC.