Grapevine quality characteristics as affected by the training system

Abstract

The aim of this research, conducted during the 2015 growing season, was to compare two different training systems, Gobelet (bush vine) and pruned upward vertical shoot positioning (VSP), through the analysis of canopy efficiency: vegetative and productive activity, as well as physiological behavior. Leaf area, shoots and light interception, and single leaf gas exchanges were measured. Furthermore, investigations in productive activity, qualitative and quantitative grape characteristics were carried out: berry samples were collected from the veraison to harvest, and sugar content, titratable acidity, pH, extractable anthocyanins and polyphenols were analyzed. The main differences between Gobelet and VSP were related to the enhancements of vegetative activity and yield (berry and cluster weights), generally due to improved exposed leaf area and hence light interception. Gobelet training system may be indicated in climates characterized by high photosynthetic active radiation (PAR), to increase yields while preserving the quality of the grapes.