Crop Load is more effective of canopy density in influencing grape berry and wine composition of Montepulciano (Vitis vinifera L.).

Four summer pruning techniques (shoot thinning at anthesis, preanthesis removal of the basal leaves and laterals of the main shoot, pre-veraison removal of the basal laterals of the shoot and cluster thinning at veraison) were compared to the sole winter pruning and evaluated in the canopy density regulation and crop level on medium vigorous Montepulciano vineyard. The sole shoot thinning at anthesis did not affect yield, cluster characteristics and berry composition. Early defoliation, compared to winter pruning, markedly reduced fruit-zone canopy density, cluster compactness and yield (-40%), but increased must soluble solids concentration, grape polyphenols (+26%) and anthocianins (+23%) concentration. Pre-veraison defoliation and cluster thinning treatments did not affect yield and berry composition. Wines obtained by early defoliated grapevines, featuring the lowest crop load allowing to enhance quality grapes, were characterized by the most prestigious characteristics. Thus, early defoliation resulted as a possible alternative and innovative technique for canopy management to control yield and obtain high quality grapes for high wines quality.