Téthal J., Baroň M., Sotolář R., Ailer S., Sochor J. (2015): Effect of grapevine rootstocks on qualitative parameters of the Cerason variety. Czech J. Food Sci., 33: 570-579.The Cerason variety is a hybrid from the cross of Merlan × Fratava varieties and its registration took place in 2008. In the category of fungus-resistant (PIWI) grapevine varieties, Cerason represents a very prospective variety. This study deals with effects of seven selected rootstock varieties (K 125AA, Amos, Börner, CR2, K5BB, K1SO4, and T5C) on qualitative parameters of Cerason juice. This experiment was established in 2011 in vineyards of Mendel University in Lednice. In the juice of the berries, the following parameters were monitored: concentrations of sugar, total acids, tartaric acid, malic acid, ratio of tartaric to malic acid (β-ratio), concentration of yeast assimilable nitrogen, and pH value. These parameters were monitored in seven-day intervals in the period of 6 weeks. The aim of this study was to identify those rootstock varieties that would be the most suitable for the given locality on the basis of contents of the aforementioned important substances. The best results were recorded in K125AA and K5BB rootstock varieties.