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IVES 9 IVES Conference Series 9 Traçability of main mineral elements on the chain “soil-leaf-must-wine” in relation to “terroir” and vintage in Loire Valley(France)

Traçability of main mineral elements on the chain “soil-leaf-must-wine” in relation to “terroir” and vintage in Loire Valley(France)

Abstract

[English version below]

Dans le cadre de recherches sur la mise en évidence et le déterminisme d’un «effet terroir »un réseau de parcelles du cépage Cabernet Franc greffé sur S04, a été suivi de 1979 à 1990 en Val de Loire (A.O.C. Saumur-Champigny, Chinon et Bourgueil). Des analyses chimiques (N,P, K, Ca, Mg, Fe, Mn, Zn) ont été réalisées sur le sol, les feuilles au stade véraison, les moûts en cours de maturation et à la vendange et enfin sur le vin, pour 18 sites (répartis dans 12unités terroirs de base) et 7 millésimes différents. Dans les conditions de cet essai, le comportement des feuilles à la véraison est relativement indépendant du millésime pour N, P,K et Ca mais fortement influencé par celui-ci pour Mg, Fe, Mn et Zn. Seul le phosphore présente une très bonne traçabilité des feuilles au vin sans relation nette avec les teneurs en phosphore assimilable du sol. Les teneurs en calcium échangeable et le pH du sol, liés à la nature (calcaire ou non) de la roche, ou bien aux apports d’amendements, expliquent la richesse relative en calcium des feuilles mais la traçabilité de cet élément ne se retrouve pas systématiquement dans les moûts et les vins. Les recherches conduites sur ce réseau ont montré que les facteurs chimiques du sol ne semblent pas jouer un rôle déterminant dans « l’effet terroir ».

To study the “terroir” effect, a network of experimental plots with Cabernet franc grafted onto S04 was followed between 1979 and 1990 in Loire Valley (A.O.C.: Saumur-Champigny,Chinon and Bourgueil), in France. Chemical analysis concerning N, P, K, Ca, Mg, Fe, Mn,and Zn elements were made on soils, leafs at véraison, musts over the ripening period and at the grape harvest, and on the wine, in 18 plots (corresponding to 12 Basic Terroir Units), on seven vintages. In our experiment conditions, the behavior of leafs at véraison was relatively independent to vintage for N, P, K and Ca but greatly influenced by it for Mg, Fe, Mn and Zn. Only phosphorus had shown a very good traçability from leaf to wine, without relation with assimilable phosphorus in soil. pH and Ca exchangeable contents in soil, due to rock natureand soil amendments, explain Ca contents in leaf but the traçability of this element did not continue up to must and wine. Results obtained with this trial showed that soil chemical factors seemed to not be predominant in the “terroir effect”.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

Lydie HUCHE-THELIER* and R. MORLAT**

* UMR A_ 462 SAGAH (INRNINH/Univ. Angers), BP 57 – F 49071 Beaucouzé cedex
** UVV : Unité Vigne et Vin, INRA, BP 57- F 49071 Beaucouzé cedex

Keywords

vigne, N, P, K,Ca, Mg, traçabilité

Tags

IVES Conference Series | Terroir 2002

Citation

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