Influence of some viticultural practices on the polyphenolic content of wines produced from cv. Agiorgitiko (<em>Vitis vinifera</em> L.)

Aims: Viticultural practices that improve light penetration and air circulation into the canopy can improve wine quality. The aim of this work is to investigate the consequences of some commonly applied viticultural practices on the polyphenolic content of cv. Agiorgitiko, an indigenous Greek grape variety. Methods and results: Three viticultural practices (training system, leaf removal and shoot elongation) were applied on cv. Agiorgitiko in the Nemea wine region and the phenolic content of the wines produced was compared. Between the two training systems (Guyot vs. double Royat), no changes in polyphenolic compounds and yield components were observed. Shoot elongation and leaf removal caused a significant decrease in the polyphenolic content of the wines. Anthocyanin content was reduced significantly due to shoot elongation, while small differences were observed in yield components. Conclusion: The study showed that increasing bunch sun exposure in warm viticultural areas may not be beneficial to the quality of the wine. Significance and impact of the study: Climate and weather conditions should be taken into account before applying practices that increase bunch exposure, especially in warm wine regions where light could be detrimental to the polyphenolic content of the wines