Terroir 1996 banner
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

Citation

Related articles…

Challenges and opportunities for increasing organic carbon in vineyard soils: perspectives of extension specialists

Increasing soil organic carbon (SOC) in vineyards enhances soil health with associated benefits for climate change resilience and mitigation.

USE OF 13C CP/MAS NMR AND EPR SPECTROSCOPIC TECHNIQUES TO CHARACTERIZE MACROMOLECULAR CHANGES IN OAK WOOD(QUERCUS PETRAEA) DURING TOASTING

For coopers, toasting process is considered a crucial step in barrel production during which oak wood (Q. petraea) develops several aromatic nuances released to the wine during its maturation. Toasting consists of applying different degrees of heat to a barrel for a specific period. As the temperature increases, thermal degradation of oak wood structure produces a huge range of chemical compounds. Many studies have identified the main key aroma volatile compounds (whisky-lactone, furfural, eugenol, guaiacol, vanillin). However, detailed information on how the chemical structure of oak wood degrades with increasing toasting level is still lacking.

Comparing different vineyard sampling densities and patterns for spatial interpolation of intrinsic water use efficiency

The need to rationalize agricultural inputs has recently increased interest in assessing vineyard variability in order to implement variable rate input applications, so-called ‘precision viticulture’. In many viticultural areas globally, precision viticulture is already widely used such as for selective harvesting and variable rate application (VRA) of inputs such as irrigation and/or fertilizer. Robust VRA relies on having a geostatistically accurate map (of one or more vineyard attributes) requiring high sampling densities, which can be cost- and time-prohibitive to obtain. Previous work on spatial interpolation using kriging have upscaled ground-based measurements, but such upscaling strategies are applicable only when vineyard conditions are spatially continuous and satisfies the assumption of second-order stationary processes. Alternatively, mixed models that combine kriging and auxiliary information, such as the regression kriging (RK) method, are more instructive for spatial predictions. In order to improve prediction accuracies, it is therefore necessary to incorporate additional information to achieve accurate spatial patterns with low error.

Juvenile-to-adult vegetative phase transition in grapevine 

The sequential activity of miR156 and miR172 controls the juvenile to adult phase transition in many plant species, where miR156 abundance decreases while miR172 increases along plant development. Very little is known about phase transition in horticultural woody species, which show substantially long vegetative phases. In grapevine, phase transition seems to be dissociated, displaying a first transition from juvenile to adult vegetative state in the first year, coincident with tendril differentiation and a subsequent induction of inflorescences in place of some of tendrils in later years under flowering inductive environmental conditions. Since grapevine is a highly heterozygous species, the generation of genetically homogeneous material for replicated transcriptomic analyses from seed-derived plants was a main challenge.

DETERMINATION OF MINERAL COMPOSITION IN CV. TERAN (VITIS VINIFERA L.) RED WINE AFFECTED BY PRE-FERMENTATIVE MASH COOLING, HEATING, SAIGNÉE TECHNIQUE AND PROLONGED POST-FERMENTATIVE MACERATIONS

This study aimed to determine mineral composition in red wine obtained from cv. Teran (Vitis vinifera L.), autochtonous Croatian grape variety. Six different vinification treatments, including the control treatment (7-day standard maceration), were performed to study the effects of: 48-hour pre-fermentative mash cooling (8 °C) followed by prolonged post-fermentative maceration of 13 days (C15), 28 days (C30), and saignée technique (juice runoff) proceeded with prolonged post-fermentative maceration of 13 days (CS15); and effect of 48-hour heating (50 °C) followed by prolonged post-fermentative maceration of 13 days (H15) and 28 days (H30) on macro- and microelements in wine.