Productive performance and physicochemical quality of grapes for processing grown on different rootstocks

The objective of this work was to evaluate the productive performance and physicochemical characteristics of the Isabel Precoce, BRS Carmem, BRS Cora, and IAC 138-22 Máximo grape (Vitis labrusca) cultivars for juice grafted onto the ‘IAC 572 Jales’ and ‘IAC 766 Campinas’ rootstocks. A randomized complete block design, in a 4*2 factorial arrangement, was used. Productive performance was evaluated through: production per plant; yield; number of clusters per vine; and physical characteristics of clusters, berries, and rachis. The physicochemical characteristics of must composition were also determined through the content of soluble solids, reducing sugars, titratable acidity, maturity index, and pH. Since there was no significant interaction between cultivars and rootstocks for most of the evaluated characteristics, each factor was analyzed separately. The ‘IAC 766 Campinas’ rootstock provided a higher yield and more suitable physicochemical characteristics for the four cultivars. However, regardless of the rootstock used, cultivars BRS Carmem, IAC 138-22 Máximo, and Isabel Precoce were more productive than BRS Cora.