BEHAVIOR OF SOME GRAPEVINE CULTIVARS FROM MURFATLAR VINEYARD IN THE SPECIAL CLIMATIC CONDITIONS OF THE WINE YEAR 2019-2020

The climate changes in Murfatlar vineyard in recent years consist inthe increase ofmonthly average temperatures, recorded in both cold and warm seasons, accompanied by an irregular distribution of rainfall during the year, which significantly influences the growth of grapevine, the quality and production of grapes.Six representative cultivars were studied, three for white wines: Chardonnay, Columna and Muscat Ottonel and three for red wines: Fetească Neagră, Mamaia and Cabernet Sauvignon. In the last two years (2019-2020) warm winters and very dry summers have led to the onset of budburst, almost simultaneously for all the studied cultivars, followed by a very weak growth and development of shoots (2020) and an acceleration development of phenophases, mainly berween veraison and ripening. Water stress during the vegetative period, a hygroscopicity below 60% between July and August and low vegetative apparatus influenced the growth ofthe berries, resulting small grapes, and a very low must yield in 2020.Concerning the quality of grape production, the studied cultivars achieved more sugar concentrations in berries up to 35.8 g/L (in 2019) and 36.0 g/L (in 2020), higher than the values obtained in normal years. In the conditions of a pronounced dry climate manifested in the two years of study, the productions were below the normal level, especialy in 2020, achieving much diminished productions for all cultivars, except the Mamaia cultivar. The Mamaia cultivar had a positive reaction, registering an increase of production, that exceeded the multiannual value by 20% in 2020 andby 10% in 2019, the concentration of sugars in the must being above the average value obtained in normal years, exceeding by 3% and 9%, respectively, the multiannual average. Statistical calculations were done using SPSS Statistics 17.0, using mainly the Duncan test for a degree of significance of 5%.