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IVES 9 IVES Conference Series 9 Definition of functional indicators of the vine to characterize wine terroirs

Definition of functional indicators of the vine to characterize wine terroirs

Abstract

La caractérisation des terroirs viticoles est traditionnellement basée sur des descripteurs de la géologie et de la pédologie des différents milieux rencontrés, couplées à des données climatiques. Cette approche peut être efficacement complétée par une description fonctionnelle, basée sur des indicateurs d’état de la vigne. Les facteurs du milieu (somme de température, alimentation hydrique, richesse minérale … ) déterminent la phénologie et le niveau des productions végétales. Mais la connaissance des caractéristiques du milieu ne permet pas a priori de repérer la combinaison effectivement déterminante. Le potentiel d’un vignoble est évalué sur le produit final: la baie de raisin, et non par la seule caractérisation physique du sol (méthode nécessaire mais pas suffisante). L’utilisation de variables intermédiaires entre les facteurs du milieu et la caractérisation des raisins permet une meilleure appréciation des terroirs.
Nous proposons trois indicateurs pouvant servir à l’exploration de la qualité au sein d’une appellation: l’abondance en 13C naturel des sucres pour l’estimation de la contrainte hydrique, le dosage de l’azote dans les feuilles et les moûts pour l’estimation de la contrainte azotée, le poids de bois de taille directement relié à la surface foliaire (relations allométriques ), pour l’estimation de la vigueur de la plante. L’objectif est de disposer d’outils rapides et faciles d’accès, contribuant à une cartdgraphie fonctionnelle du vignoble. Ces outils permettent d’étudier la part prise par les différents facteurs impliqués dans la constitution de la qualité de la baie de raisin, au cours d’un cycle végétatif, pour le terroir considéré.

Characterization of terroirs is traditionally based on descriptors of the geology and pedology of various soils surrounding, coupled to climatic data. This approach can effectively be supplemented by a functional description, based on indicators of statè of the vineyard. The factors of the environment (thermal time, water availability, mineral richness … ) fix the phenology and the level of the productions. But the knowledge of the characteristics of the environment does not a priori allow to track down the effectively determining combination.
The potential of a vineyard is evaluated on the end product: the grape berry, and not by the only physics characterization of the soils (necessary but not sufficient method). The use of intermediate variables between the factors of the environment and the characterization of the grapes allows a better appreciation of the soils.

We propose three indicators being able to be used for the browsing of quality within, an appelation: the abundance in natural 13C of sugars for the estimate of the water restriction, the measurement of the amount of nitrogen in leaves and musts for estimate of the nitrogenous constraint, the pruning weights directly linked to the leaf aera (allometric relations), for estimate of the vigor of the plant. The objective is to have fast and easily accessible tools, contributing to a functional cartography of the vineyard. These tools make possible to study the share of the various factors implicated in the constitution of the grape berry quality, during a vegetative cycle, for the terroir considered.

 

 

 

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

GOUTOULY, J.-P. (1), SOYER, J.-P. (1), VAN LEEUWEN C. (2) and GAUDILLERE J.-P (1)

(1) INRA-AGRONOMIE, Ecophysiologie & Agronomie Viticole, 71, avenue Edouard Bourleaux – B.P.81 33883 Villenave d’Ornon cedex
(2) ENITA de Bordeaux, 1 cours du Général de Gaulle, BP 201, 33175 Gradignan cedex

Keywords

Vigne, déficit hydrique, discriminations isotopique, ?C13, biomasse, alimentation azotée, sol, terroir
Vine, water deficit, isotope discrimination,? C13, biomass, nitrogen supply, soil, terroir

Tags

IVES Conference Series | Terroir 2002

Citation

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