Evaluation of soil and canopy management strategies in highly sustainable viticultural systems

Abstract

Since 2008, long term research has been conducted in a hilly, organically managed vineyard of cv. Sangiovese located in Northern Italy (Faenza, Ravenna), with the aim of innovating and improving the production process, by establishing highly sustainable viticultural systems. Different soil (e.g. intercropping) and canopy managements (e.g. post-veraison trimming and defoliation, “semi-ballerina” effect) strategies and the use of biodynamic preparations have been evaluated. Neither fertilizers nor irrigation water were used. The vines have gradually achieved an appropriate vegetative-productive balance, with a satisfactory yield, optimal nutritional status, high quality grapes and wines. The use of biodynamic preparations (500, 500k, fladen, 501) did not modify fruit yield, soluble solid concentration, pH and titratable acidity of the berry juice. Post-veraison trimming reduced bunch weight and fruit yield compared to trimming at fruit set. The effects of biodynamic production practices on composition and sensory attributes of Sangiovese wines were examined in the 2 years (2009 and 2010) during conversion from organic (ORG) to biodynamic (DYN) cultivation method. During the first year (2009), the DYN wines were characterized by low alcohol strength, colour intensity, total polyphenols, monomeric anthocyanins and catechin. Conversely, in the second year, DYN wines differed from the organic wines being lower in terms of total polyphenols and phenolic compounds, including polymeric pigments, co-pigmentation, tannins and iron-reactive polyphenols. The ORG wine produced on 2009 showed a more complex aroma profile; however, sensory differences between ORG and DYN wines were almost indistinguishable during the second year. The concentrations of ochratoxin A and biogenic amines were far below health-hazard threshold. Overall, the data indicate that the highly sustainable cultivation methods enable the attainment of healthy, productive vines producing good wines.