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IVES 9 IVES Conference Series 9 Influence des facteurs naturels du terroir sur la maturation du raisin en Alsace

Influence des facteurs naturels du terroir sur la maturation du raisin en Alsace

Abstract

Une étude de l’influence des facteurs du milieu sur la maturation du raisin dans les conditions de l’Alsace est réalisée. L’accent est mis sur l’analyse du mésoclimat et du pédoclimat. L’expérimentation est conduite sur un réseau de parcelles de gewurztraminer greffé sur SO4. Les conditions de production sont uniformisées sur l’ensemble du dispositif. Une gamme de terroirs couvrant les grandes unités géomorphologiques du vignoble est prise en compte. Les principaux paramètres climatiques sont mesurés durant toute la phase végétative, des mesures continues de la température du sol dans la zone racinaire et hebdomadaire du potentiel foliaire de base permettent le suivi régulier du pédoclimat. La réponse de la plante est enregistrée au travers de mesures classiques des paramètres de croissance, de développement, de production et de maturation. L’étude montre que (i ) les caractéristiques mésoclimatiques des terroirs plus ou moins modulées par la température du sol dans la zone racinaire jouent un rôle majeur sur le niveau de maturité du raisin atteint en fin de cycle, (ii) les conditions d’alimentation en eau, dans le cas d’une contrainte modérée, peuvent anticiper et accélérer les processus de maturation, (iii) l’acidité des moûts est fortement influencée par l’état physiologique de la vigne au moment de la véraison lui même directement lié à l’intensité de la contrainte hydrique.

DOI:

Publication date: March 25, 2022

Issue: Terroir 1996

Type : Poster

Authors

E. LEBON (1), V. DUMAS (2), R. MORLAT (3)

(1) UVVM, UFR Viticulture, 2 pl. Viala, 34060 MONTPELLIER (FRANCE)
(2) INRA, Laboratoire d’Agronomie, 28 rue de HerrIisheim. 68021 COLMAR (FRANCE)
(3) INRA, UVV, 42 rue G. Morel, 49071 BEAUCOUZE (FRANCE)

Tags

IVES Conference Series | Terroir 1996

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