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IVES 9 IVES Conference Series 9 Optimisation de la fertilisation du Cot sur le Causse de l’Appellation d’Origine Contrôlée Cahors

Optimisation de la fertilisation du Cot sur le Causse de l’Appellation d’Origine Contrôlée Cahors

Abstract

L’aire d’Appellation d’Origine Contrôlée de Cahors (Lot) couvre une superficie de 21700 ha, répartis sur 45 communes, dont seulement 4300 sont plantés en vigne. Le cépage principal de cette A.O.C. est le Cot noir qui représente 70 % de l’encépagement, conférant ainsi leur typicité aux vins de cette région ; mais malgré cette importance, à notre connaissance, sa physiologie est restée assez peu étudiée.

Sur cette A.O.C. Cahors, traditionnellement on distingue le vignoble implanté sur le plateau calcaire : le Causse et celui de la vallée : terrasses alluviales du Lot et cônes d’éboulis. Nous avons choisi le Causse qui couvre 70 % de l’A.O.C., et correspond au quart environ de la superficie totale plantée en vigne. Sur différentes parcelles de ce terroir, nous avons réalisé un suivi sur plusieurs années par analyse de sols, de sous sols et par diagnostic foliaire. Les résultats d’analyse de limbes ont permis de déterminer, sur cette zone pédo-climatique homogène, des teneurs optimales en éléments minéraux pour ce cépage. Valeurs de référence permettant de pratiquer une fertilisation raisonnée qui est cependant à moduler en fonction des fluctuations climatiques interannuelles (Garcia et al. 1985).

DOI:

Publication date: March 25, 2022

Type: Poster

Issue: Terroir 1996

Authors

G. BRUN (1), M. GARCIA (1), F. DEDIEU (2), F. LAFFARGUE (3)

(1) Institut National Polytechnique. E.N.S.A.T.
145, Avenue de Muret, 31076 Toulouse cedex, France
(2) Faculté de Pharmacie
35, Chemin des Maraîchers, 31062 Toulouse cedex, France
(3) Maison du Vin de Cahors
B.P. 199, 46004 Cahors cedex, France

Tags

IVES Conference Series | Terroir 1996

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