The effect of genotype on table grapes soluble solids content
Department of Horticulture, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 64, EE51014 Tartu, Estonia; *Correspondence: email@example.com
Sugar concentration in fresh consumed table grapes is mainly connected with technological maturity and primarily expressed by soluble solids content. The EU Regulation has laid down maturity requirements for Vitis vinifera L. cultivars (OJ L 157, 15.6.2011). The lowest allowed soluble solids content is 13 °Brix for seeded cultivars and 14 °Brix for seedless cultivars. In cool climate there are mainly cultivated grape hybrid cultivars which refractometric index is not regulated with this regulation. The aim of the present experiment was to investigate the accumulation dynamics and content of soluble solids from the beginning of veraison to harvest in table grapes with protected cultivation condition. The research was conducted with 3 black (‘Osella’, ‘Kosmonavt’, ‘Mars’), 3 red (‘Swenson Red’, ‘Somerset Seedless’, ‘Canadice’) and 2 white (‘Arkadia’, ‘Supaga’) vine cultivars in 2013 and 2014. The results of the study indicated, that fruits of all table grape cultivars achieved the minimum content of soluble solids required for table grapes. Two years mean of soluble solids content varied among black, red and white grape cultivars respectively from 15.0 to 22.1 °Brix, from 15.6 to 22.5 °Brix and from 13.9 to 18.9 °Brix. The highest soluble solids content was observed in both years among black cultivars in Osella, among red cultivars in Somerset Seedless and among white in Supaga.