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Vineyard performance and fruit quality of some interspecific grapevine cultivars in cool climate conditions

Abstract A study of 13 grapevine cultivars was carried out in a vineyard located near Krakow (Poland) in order to identify the most suitable grapevine cultivars for cool climate regions. The vines’ vigour, yield and the yield efficiency index were studied in the years 2010-2013. The grapes were analysed to determine soluble solids content (SSC), titratable acidity, total polyphenol content (TPC) as well as fruit antioxidant activity (FRAP). Moreover, organic acid concentrations (tartaric, malic, citric and ascorbic) were ascertained. Significant fluctuations in yield and quality were caused by variable climatic conditions during the vegetation period, especially before the vintage. SSC varied from 15.7°Brix (‘Swenson Red’) to 20.8°Brix (‘Frontenac’). The highest sugar:acid ratio was measured for ‘Regent’ as well as for ‘Hibernal’ and ‘Muskat Odesskij’ among white grapes. The lowest concentration of tartaric acid was measured for ‘Frontenac’ (1.03 g L-1) as well as ‘Jutrzenka’ (1.76 g L-1). The latter cultivar tended to accumulate one of the highest amounts of malic and citric acid. The highest total polyphenol content along with outstanding antioxidant activity was measured for the following red cultivars: ‘Frontenac’, ‘Leon Millot’ and ‘Marechal Foch’. The most promising cultivars were ‘Seyval Blanc’, ‘Aurora’ and ‘Regent’, which performed well in terms of their moderate vigour, increased fruitfulness and consistently higher yields.