Influence of mechanical canopy management and differential RDI stress on the phenolic and volatile aroma composition of Syrah wines.

摘要

A field study was conducted to determine the interactive effects of canopy management and regulated deficit irrigation (RDI) on the canopy architecture; yield components, Ravaz index, berry skin and wine phenolics, and the volatile wine aroma composition over a 2-yr growing period. Control vines were hand pruned to 22 two-node spurs. The mechanical canopy treatments consisted of mechanically box pruning vines to a 100 mm bearing surface, then mechanically shoot thinning to a density of five (CLL), or seven (CLM) count shoots per 30 cm of canopy or mechanically box pruning with no further manipulation (CLH). Control vines were irrigated to 70% evapotranspiration ET o from fruit set until harvest (RDIC). Other vines received 50% of ET o between fruit-set and veraison and 70% of ETo thereafter (RDIE). Polymeric tannins, pigmented polymers, and malvidin concentrations were optimized in finished wine with the CLM x RDIE treatment applications. There was an increased interaction of canopy management and RDI method on volatile aroma composition in 2010 compared to 2011, including IBMP (3-isobutyl-2-Methoxypyrazine). The study identified a mechanical canopy management method that can be used in combination with differential regulated irrigation stress that reduced input costs, enhanced berry skin and wine phenolic composition, while achieving vine balance that provides for sustainable production.