Scion Influence and Rootstock Specificity in Grafted Grapevines: Insights into Graft Affinity, Growth, and the Dynamics of Nutrient Acquisition.

Grafting is a crucial strategy for improving stress resistance and fruit quality in grape production. However, our understanding of the specific roles of rootstocks in graft establishment, vine growth, and nutrient acquisition remains limited. This study evaluated the relevant traits of three worldwide wine grape cultivars grafted onto eight rootstocks, aiming to clarify the inherent characteristics of individual rootstocks and provide insights for their better understanding and utilization. The rootstock showed significant effects on petiole mineral levels with consistent patterns, even across developmental stages and years. For example, 5BB consistently accumulated Ca at all stages, while Beta demonstrated strong Mn uptake. Additionally, 101-14M and 110R specifically enriched B at the flowering stage. The scion showed a great influence on post-graft growth and mineral absorption. Specifically, 'Cabernet Sauvignon' (CS) exhibited superior performance in macronutrient accumulation, whereas 'Petit Verdot' (PV) showed distinct advantages in micronutrient. From flowering to veraison, the dominant mineral profile shifted from N, P, and B to Ca, Mg, and Cu, with the scion's influence becoming evident at veraison. These findings enhance our understanding of rootstocks and provide a reference for their utilization.