ABSTRACT Phenology, bunch morphology, and must quality are essential factors to the selection of grapevine cultivars for winemaking. This study aimed to evaluate five grapevine hybrids grafted onto two rootstocks, looking for fruit with the best characteristics for producing wine. The hybrids studied were ‘BRS Lorena’, ‘IAC 21-14 Madalena’, ‘Moscatel de Jundiaí’, ‘Moscato Embrapa’ and ‘SR 0.501-17’ grafted onto ‘IAC 572 Jales’ and ‘IAC 766 Campinas’ rootstock. Phenology was evaluated weekly, and the number of days from pruning to sprouting, flowering, and maturation was calculated. Fruit production, bunch morphology, and must quality were evaluated for each genotype and rootstock. ‘SR 0.501-17’ was classified as a genotype with a medium cycle, with fruit maturing 20 days earlier than the other hybrids, which were, therefore, classified as late-cycling. No interaction was noted between hybrids and rootstocks relative to bunch morphology. The must of ‘Moscato Embrapa’ grafted onto ‘IAC 766 Campinas’ rootstock had higher maturation index than that grafted onto ‘IAC 572 Jales’ rootstock. ‘BRS Lorena’ and ‘SR 0.501-17’ produced smaller berries, must with medium acidity, and higher soluble solid contents, as compared with other hybrids, resulting in the best bunch morphology and must quality for winemaking.

ABSTRACT This study evaluated the cycle duration, physicochemical characteristics of fruits and climatic adaptation of the ‘SR 501-17’ hybrid grape grafted on four rootstocks for the production of white wine. We tested four rootstocks, ‘IAC 766 Campinas’, ‘IAC 572 Jales’, ‘IAC 571-6 Jundiaí’ and ‘IAC 313 Tropical’, planted in two climatic regions, Cfa and Aw, in the state of São Paulo, Brazil in the cultivation years 2014 and 2015. Cycle duration, production, cluster weight, number of berries per bunch, content of soluble solids, titratable acidity, a maturation index and the weight, length and width of berries were evaluated. A principal component analysis characterized the cultivar for both climatic regions and years. The rootstock did not influence the cycle, production or physicochemical characteristics of the ‘SR 501-17’ hybrid. The soluble-solid content in the must was higher and the production cycle in 2014 was longer for the Cfa climate. The production cycle was shorter and the weight and width of the berries were lower, mainly in 2015, for the Aw climate. The cycle was thus longer, production was higher and the chemical characteristics were better for the ‘SR 501-17’ hybrid under Cfa conditions, regardless of the rootstock.