Effect of canopy management techniques on the nutritional quality of Montepulciano grapevine in Puglia (Southern Italy)

Aims: Tests were carried out to assess the effects of early defoliation, cluster thinning and cluster cutting on the basic and nutritional composition of musts and wines of Vitis vinifera L. cv. Montepulciano.Methods and results: Both production and quality variables of the musts were evaluated. Antioxidant activity was determined on berries and on wines, as were the phenol and anthocyanin concentrations. The wines were compared by sensory evaluation. The results attested to a positive effect of the treatments on grape composition and on antioxidant activity in the berries.Conclusions: The tested treatments (DP = early defoliation; D3 = cluster thinning 30 %; D5 = cluster thinning 50 %; T3 = cluster cutting 30 %; T5 = cluster cutting 50%) increased both the soluble solids and the pH of the musts and enhanced the nutritional quality (based on antioxidant concentration) of both the grapes and the wine.Significance and impact of the study: The adopted techniques may be useful in cases in which yield control is required and/or the composition of the musts and wines needs to be modified based on the concentration of sugars in the berries. However, the variable response of the vines to the various techniques suggests that each cultural practice be evaluated in relation to specific oenological objectives.