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IVES 9 IVES Conference Series 9 Hierarchy of the role of climate, soil and cultivar in terroir effect can largely be explained by vine water status

Hierarchy of the role of climate, soil and cultivar in terroir effect can largely be explained by vine water status

Abstract

Le terroir peut être défini comme un écosystème dans lequel la vigne interagit avec le climat et le sol et dont la résultante est le vin. Dans ce travail, les trois principaux composants de l’effet terroir, à savoir le climat, le sol et le cépage ont été étudié simultanément. Le développement de la vigne et la constitution du raisin de Vitis vinifera L. cv Merlot, Cabernet franc et Cabernet-Sauvignon ont été comparés sur trois parcelles non irriguées, comportant respectivement un sol graveleux (G), un sol à sous-sol très argileux (C) et un sol sableux à nappe d’eau à portée des racines (S). L’effet du climat a été étudié à partir des variations climatiques annuelles (effet millésime) sur la période 1996-2003. Les effets du climat, du sol et du cépage ont été hautement significatif sur la plupart des variables mesurées. Sur une majorité de variables, l’effet du climat a été plus important que l’effet du sol et du cépage. La plupart des variables sont corrélées à l’intensité du déficit hydrique, qui a été évalué par la mesure du potentiel foliaire de base et par la mesure de la discrimination isotopique du carbone 13 sur les sucres du moût (δ13C). L’effet du climat et du sol semblent agir principalement par leur incidence sur le régime hydrique de la vigne.

Terroir can be defined as an interactive ecosystem, in a given place, including climate, soil and the vine. The three main components of terroir effect, soil, climate and cultivar, have been studied simultaneously. Vine development and berry composition of non-irrigated Vitis vinifera L. cv Merlot, Cabernet franc and Cabernet-Sauvignon were compared on a gravely soil (G), a soil with a heavy clay sub soil (C) and a sandy soil with a water table within the reach of the roots (S). The influence of climate was assessed with year-to-year climatic variations (vintage effect) over the period 1996 to 2003. Effects of climate, soil and cultivar on vine behaviour and berry ripening were highly significant. On most variables, the impact of climate was greater than the effect of soil and cultivar. Most variables were correlated with the intensity of vine water stress, which was assessed by measurements of pre-dawn leaf water potential and carbon isotope discrimination measured on grape sugar (δ13C). It is likely that the effect of climate and soil on fruit quality is mediated through their influence on vine water status.

DOI:

Publication date: January 13, 2022

Issue: Terroir 2004

Type: Article

Authors

C. van Leeuwen (1), P. Friant (1), M.-E. Jaeck (1) S. Kuhn (1) and O. Lavialle

(1) ENITA de Bordeaux, 1, Crs du G n ral de Gaulle, BP 201, 33175 Gradignan-cedex, France

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Keywords

terroir, soil, climate, cultivar, vine, Vitis vinifera, Merlot, Cabernet franc, Cabernet-Sauvignon, water deficit, leaf water potential

Tags

IVES Conference Series | Terroir 2004

Citation

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