T. Yoncheva1*, A. Iliev1, F. Emurlova2
1Department of Vine Selection, Enology and Chemistry, Institute of Viticulture and Enology, 5800 Pleven, Agricultural Academy, Bulgaria
2Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria
(Manuscript received 20 June 2022; accepted for publication 11 November 2022)
Abstract. The rootstock had a significant impact on the quantity and quality of grapes of the varieties grafted on it. That had been determined by the different growth strength of the rootstocks, their different absorption capacity and compatibility with the cultivated vine. During the period 2017-2020, a study was carried out on the agrobiological and technological properties of grapes and wine of the Kaylashki Rubin variety, grafted on vine rootstocks SО4, 110 Rihter, 44-53 Malegue and Fercal. Differences in the investigated indicators were found as a result of the influence of the used rootstocks. A mechanical analysis was made to determine the composition and structure of the clusters and berries. For the period, the highest average yield per vine was reported for Fercal rootstock, while the best theoretical yield had the variant on 44-53 Malegue rootstock. The chemical composition of grapes and experimental wines had been determined. On the average for the period the highest sugar accumulation and respectively the lowest titratable acids in grapes were reported in the variant of 44-53 Malegue rootstock. The opposite relationship was observed for 110 Richter. Differences in the chemical composition of the wines depending on the used rootstocks were found. The wines from 44-53 Malegue variant had the highest average alcohol content and sugar-free extract, but the lowest rates of titratable acids. The average amounts of the total phenolic compounds and anthocyanins in the wines from the variants of the different rootstocks were close. Their values were the lowest in the samples 2017 vintage. The rootstock type also affected the organoleptic properties of the Kaylashki Rubin wines; however, there was no common trend for the studied period. In 2018 and 2020, the samples from the 110 Rihter variant showed the best tasting qualities.