 IVES 9 IVES Conference Series 9 Accumulation of polyphenols in Barbera and Nebbiolo leaves during the vegetative season

Accumulation of polyphenols in Barbera and Nebbiolo leaves during the vegetative season

Abstract

Grapevine berries produce thousands of secondary metabolites of diverse chemical nature that have been largely detailed in the past due to their importance for defining wine quality. The wide Vitis vinifera diversity, resulting in thousands of different varieties well detailed in many studies regarding berries, is still not investigated in vegetative organs, leaves in particular. Deepening knowledge related to this aspect could be of great interest for many reasons (for example the possibility of using leaf extract for pharmaceutical, cosmetic and nutrition purposes) but, above all, for understanding the susceptibility of different grapevine varieties to pathogens. Recent studies have demonstrated that leaves of different varieties display a wide range of secondary metabolite concentrations and different profiles and that constitutive polyphenols can result in diverse susceptibility to fungi infection. Moreover, also the reaction of the vine to a pathogen attack can pass through the alteration of specific secondary metabolite accumulation. We have undertaken a study regarding the quantification and identification of main polyphenols in the healthy leaves of different Vitis species and of different vinifera varieties. In this work we report preliminary data regarding the evolution of polyphenol accumulation in the leaves of Vitis vinifera cv Barbera and cv Nebbiolo during the vegetative season. The two varieties are known to have a very different polyphenolic profile at the berry level; at the leaf level significant differences were detected as well, paving the way to new insights about the constitutional natural susceptibility of different grapevine varieties to pathogens.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Alessandra Ferrandino*, Olga Kedrina, Vittorino Novello

*DISAFA UNITO

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Citation

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