Yield and physicochemical characteristics of ‘BRS Magna’ and ‘Isabel Precoce’ grapes influenced by pruning in the SãoFrancisco river valley

The objective of this study was to evaluate the productive performance and physicochemical characteristics of ‘BRS Magna’ and ‘Isabel Precoce’ grapes influenced by two types of pruning. The experiment was carried out during two growing seasons in a commercial vineyard of Petrolina, PE, in the period 2013-2014. Treatments were represented by two cultivars, ‘Isabel Precoce’ and ‘BRS Magna’, and two types of pruning, with selection during plant formation (P1) and without selection (P2) of lateral branches, using a randomized experimental block design, in subdivided plots and four replicates. After pruning P2, the amount of buds kept on vines was greater than after pruning P1, favoring an increase in yield. However, the sizes of bunches and berries, content of soluble solids, and titratable acidity were not influenced by the pruning type. In general, the sizes of bunches and berries in ‘BRS Magna’ were larger than in the ‘Isabel Precoce’ cultivar. Conversely, content of soluble solids and titratable acidity varied among cultivars as a function of production cycle and type of pruning; however, within the standards described for both cultivars and accepted by the Brazilian legislation.