Determination of Grafting Success and Carbohydrate Distributions of Foxy Grape (Vitis labrusca L.) Varieties Grafted on Different American Grape Rootstocks

This study aimed to determine the grafting success and carbohydrate distributions for newly registered foxy grape varieties grafted on different American grapes and grown in humid conditions in the Black Sea Region of Turkey. In the study, ‘Rizessi’, ‘Çeliksu’, ‘Ülkemiz’, ‘Rizellim’, and ‘Rizpem’ foxy grape varieties were grafted on 140Ru, SO4, and 110R American rootstocks. The graft success, growth, and development characteristics were determined, and carbohydrate accumulations and distributions at the graft area, under the graft area (rootstock), and above the graft area (scion) of the grafted grapevines in the dormant period were also determined. The highest graft success rate was 100.00% in the combinations of ‘Rizessi’/SO4, ‘Rizellim’/SO4, ‘Rizpem’/SO4, ‘Rizellim’/110R, and ‘Rizpem’/110R. The percentage of vine saplings ranged from 86.00% (‘Rizellim’/SO4) to 27.14% (‘Rizpem’/140Ru). Regarding carbohydrate distribution, the ‘Rizessi’/140Ru, ‘Rizessi’/SO4, ‘Rizessi’/110R, ‘Çeliksu’/SO4, ‘Çeliksu’/110R, ‘Ülkemiz’/SO4, ‘Rizellim’/140Ru, ‘Rizellim’/SO4, ‘Rizpem’/SO4, and ‘Rizpem’/110R combinations showed a balanced distribution. The highest total carbohydrate accumulation (100.41 mg·L−1) was detected in the root region of the ‘Ülkemiz’/SO4 combination. On the other hand, vine sapling rate enhanced as carbohydrate accumulation increased in the grafting area. The SO4 American rootstock was found to be more successful than the others.