Evaluation of the influence of rootstock cane characteristics on grafting success rate

The success of grafting in grapevine nurseries can vary significantly depending on the wood used, even if the same scion and rootstock are used, yet the underlying causes of this variation remain poorly understood. To elucidate the factors influencing grafting success, rootstock wood (Vitis berlandieri x V. rupestris cv. 110 Richter) from ten production fields - each representing different rootstock origins - in Spain and France was characterised and grafted to cv. Tempranillo, and grafting success rates were subsequently determined. Histological analysis of the rootstock canes was carried out to evaluate tissue dimensions (pith, xylem, and phloem), number of xylem vessels, and hydraulic conductivity, revealing significant differences, particularly in the size and presence of large vessels. Metabolite analysis (starch, sucrose, glucose, fructose, and proteins) and isotopic composition (δ 13C and δ 15N) further differentiated the batches. Grafting success rates were recorded after uprooting and showed positive associations with parameters of water status (δ 13C), nitrogen assimilation (δ 15N), and anatomical characteristics of the rootstock canes. These findings underscore the complex interaction of physiological, anatomical, and environmental factors influencing grafting outcomes in grapevines.