Influence of thinning grapes on vine block wintering, in five grape varieties for red wines, cultivated in NW Romania.

Five grape varieties for red wines (Pinot noir, Merlot, Cabernet Sauvignon, Syrah andBurgund mare) were tested in 2009-2010, in NW Romania (RAƒtești wine-growing center), under twotypes of cultural technology: thinning and without thinning grapes. The work of fruit loadstandardization through thinning grapes has been made at the beginning of veraison (third decade ofJuly in 2009 and the first decade of august in 2010). In this study, were made observations regardingtemperatures during the period 2009-2010 and the level of critical temperature during winter, in orderto establish the quantity of carbohydrates (g %) from vine shoots and bud viability (%). Theexperiment was a bifactorial series (cultivar x fruit load standardization) with five grape wine varietiesgrown and two different applied technologies: thinning and without thinning grapes. Regardless of thestandardization of fruit load, Syrah variety distinguished with high carbohydrate values of string,obtained during the two years of testing (15.94 g %) meaning good adaptability of the variety toclimatic conditions in the RAƒtești wine area. The other four species showed significant differencesfrom the Syrah variety, however, between them, the differences are insignificant. The two variantsanalyzed (thinning and no thinning) had a significant influence on the accumulation of reservesubstances. The string bud viability was high (over 85 %) to all five species tested.