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IVES 9 IVES Conference Series 9 Water status, nitrogen status and leaf area/ crop ratio effect on aromatic potential of vitis viniferaberries : example of Sauvignon blanc

Water status, nitrogen status and leaf area/ crop ratio effect on aromatic potential of vitis viniferaberries : example of Sauvignon blanc

Abstract

[English version below]

Les effets de l’état hydrique et de l’alimentation en azote sur le potentiel aromatique des raisins de Sauvignon blanc ont été mesurés sur des vignobles du Bordelais. Les déficits hydriques ont été caractérisés par le potentiel tige déterminé en milieu de journée ΨTmin)­. L’alimentation en azote a été étudiée à partir d’une zone carencée en azote. Une part de cette zone a été supplémentée avec de l’azote minéral. La teneur en précurseurs cystéinylés des raisins varie avec l’état hydrique de la vigne. Comparés à une alimentation en eau non limitative, les déficits hydriques modérés exercent une influence positive sur la teneur en précurseurs cystéinylés des raisins. La correction de la carence en azote a entraîné une forte augmentation des teneurs en précurseurs cystéinylés et en glutathion dans les baies. Inversement, cet apport d’azote a induit une diminution de la teneur en composés phénoliques Un rapport surface foliaire sur rendement élevé exerce une influence positive sur la teneur en précurseurs cystéinylés des baies.

Water status and nitrogen status influence on berries aromatic potential of Vitis vinifera L. cv. Sauvignon blanc have been surveyed in Bordeaux vineyard. Vine water deficit have been measured with the determination of midday stem water potential. Nitrogen status have been surveyed on the basis of deficient vines. Sorne of the vines have been fertilized with mineral nitrogen. S-cysteine conjugates, precursors of the volatile thiols have been determined. Berries precursors content is under the dependence on vine water status. Moderate water deficits have a positive effect on the berries precursors content. The Correction of the nitrogen deficiency provoked a strong increase of berries precursors and glutathion content, whereas the phenolic content decreased. A high leaf area / crop balance has played a positive influence on the berries precursors content.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

Xavier CHONÉ (1,2), Valérie LAVIGNE-CRUEGE (1), Virginie MOINE-LEDOUX (1), Philippe CHÉRY (2), Takatoshi TOMINAGA (1), Denis DUBOURDIEU (1)

(1) Faculté d’Oenologie de Bordeaux, Université Bordeaux 2 Victor Ségalen, 351 Crs de la Libération, 33405 Talence Cedex, France
(2) ENITA de Bordeaux, 1 Crs du Général de Gaulle, 33175 Gradignan Cedex, France

Keywords

terroir, vigne, déficit hydrique, potentiel tige, surface foliaire, alimentation en azote, fertilisation, raisins, arômes, précurseurs cystéinylés, thiols, composés réducteurs, glutathion, composés phénoliques.
terroir, vine water deficit, stem water potential, leaf area, nitrogen status, fertilization, varietal aroma, precursors of the volatil thiols, reductive compound, berry glutathion and phenolic content

Tags

IVES Conference Series | Terroir 2002

Citation

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