Resumen de Effects of foliar application of inactivated yeast on the phenolic composition of Vitis vinifera L. cv. Agiorgitiko grapes under different irrigation levels
Charikleia Kogkou, Evangelia Chorti, Maria Kyraleou, Stamatina Kallithraka, Stefanos Koundouras, Gerard Logan, Ioannis Kanakis, Yorgos Kotseridis
Recent climate changes have caused the rising of average growing season temperatures leading to the advancement of vine phenological stages and to earlier harvests. This could result in the production of grapes with advanced berry sugar accumulation, but incomplete phenolic ripeness, thereby jeopardizing wine quality. This study aims to evaluate the effects of the application of a new product consisting of yeast derivatives on the phenolic maturity and composition of Agiorgitiko grapes and wines, under contrasting water conditions. The experiment was arranged as a 2×2 factorial design in a commercial vineyard situated in southern Greece, combining foliar spraying with LalVigne® Mature (two applications after veraison and an untreated control) and water conditions (deficit irrigation and nonirrigated). Irrigation accelerated berry sugar accumulation, increased berry weight and anthocyanin content, and decreased skin tannin concentration. Spraying with yeast derivatives did not affect phenolic content of berry components, and it had no effect on must attributes. Foliar application of yeast derivatives resulted in a higher phenolic potential of the produced wines, only when combined with irrigation.
