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IVES 9 IVES Conference Series 9 Résistance stomatique et caractérisation hydrique des terroirs viticoles

Résistance stomatique et caractérisation hydrique des terroirs viticoles

Abstract

La caractérisation des terroirs viticoles se fonde sur divers types de démarches :
– démarche phytoécologique
L’analyse de la répartition des populations végétales naturelles permet une caractérisation écologique des milieux cultivés aux plans thermique, hydrique et trophique; elle oriente le choix ou la sélection des plantes (ou des cépages) à cultiver (Astruc et coll., 1984, 1987; Delpoux, 1971; Jacquinet et Astruc, 1979). Cette démarche a donné de bons résultats dans les zones où la topographie est l’élément déterminant d’une différenciation écologique des terroirs.
– démarche écogéopédologique
La mise en oeuvre de ce concept analytique fait appel aux méthodes et aux techniques de la géologie, de la pédologie et de l’agronomie, pour l’étude des sols, et des systèmes racinaires. Pour les Pays de Loire et avec le Cabemet franc, Morlat (1989, 1992) a pu hiérarchiser les potentialités agroviticoles des terroirs et distinguer :
1 – des terroirs à forte potentialité viticole qui permettent d’obtenir des vins de qualité, quelles que soient les conditions climatiques du millésime
2 – des terroirs à faible potentialité viticole pour lesquels les vins obtenus présentent toujours une ou plusieurs déficiences
3 – des terroirs à potentialité variable (forte ou faible) selon la climatologie de l’année

Ces deux démarches de caractérisation des terroirs intègrent de façon indirecte le fonctionnement de la vigne,
– soit d’une manière globale pour la méthode phytoécologique,
– soit par l’intermédiaire d’un certain nombre de variables telles que le système racinaire, la précocité, la maturation des baies, pour la méthode écogéopédologique.
En fait, comme le note Morlat (1992), « un bon diagnostic de la valeur viticole d’un terroir ne peut être réalisé que si le système sol-cépage-atmosphère est considéré dans son ensemble. » Tous les aspects du fonctionnement du système doivent être considérés simultanément, ce qui n’est pas aisé.

Toutefois, parmi les fonctions physiologiques essentielles, l’alimentation hydrique constitue un élément déterminant de la qualité d’une récolte (Mériaux et coll., 1990). C’est pourquoi, nous avons effectué un suivi de la nutrition hydrique de quelques parcelles de vigne du Frontonnais pendant les phases de véraison et de maturation.

DOI:

Publication date: March 25, 2022

Type: Poster

Issue: Terroir 1996

Authors

D. VIGNES (1), P. GALLEGO (2), M. GARCIA (2), C. TOSCA (1)

(1) CESBIO, 18, Av. Edouard Belin, 31055 Toulouse Cédex 
(2) ENSAT, 145 Av. de Muret, 31076 Toulouse Cédex 

Tags

IVES Conference Series | Terroir 1996

Citation

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