Study regarding variability of yield components in some grapevine varieties for white wines

The purpose of the study was to evaluate the variability of several white wine grape varieties in order to highlight their main quantitative and qualitative parameters. The study was carried out during two growing seasons (2017-2018) in the Pâncota locality area, Arad County, in the pedo-climatic conditions from the Miniş-Măderat vineyard. Research was organized in randomized block design with three replications. The morphological parameters involved in the research were: the number of bunches on the vine, the bunch weight, the number of berries in the bunch and the grape yield on the vine. The highest number of bunches on the vine was recorded in the Pinot Gris and Italian Riesling varieties, while the Traminer Rose variety recorded the lowest values for the same parameter. The Muscat Ottonel variety recorded the highest values ​​for the average weight of the bunch, with very significant positive results. The Muscat Ottonel variety also recorded the highest number of berries / bunch during the research. The same variety achieved the highest yield, of 3027.10 g /vine, significantly higher than the other varieties, with over 141.5% compared to Pinot Gris, to over 180% compared to Traminer Rose. In the Traminer Rose variety, lower values of the grape yield on the vine were recorded, suggesting a specific adaptation of the variety to less favourable environmental conditions. Therefore, this variety can return lower but constant yields in the unfavourable environmental conditions.