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IVES 9 IVES Conference Series 9 Différenciation de parcelles de Chenin du Val de Loire, a l’aide de l’etude des flores fongiques des raisins, en utilisant l’outil DGGE

Différenciation de parcelles de Chenin du Val de Loire, a l’aide de l’etude des flores fongiques des raisins, en utilisant l’outil DGGE

Abstract

Depuis le millésime 2002, une étude est menée sur la diversité de la flore fongique de parcelles du cépage chenin, situées essentiellement sur les appellations de Vouvray et Montlouis ; deux appellations séparées par le fleuve nommé la Loire. Les parcelles se situent dans des conditions pédoclimatiques différentes, qui se retrouvent au travers des suivis de maturité et l’état sanitaire.

L’objectif est d’utiliser la flore fongique comme facteur de différenciation entre les parcelles, et d’évolution au cours de la maturité. C’est dans ce cadre qu’un outil d’écologie microbienne a été utilisé : Denaturating Gradient Gel Electrophoresis (DGGE). Après une étude spécifique sur les moisissures des raisins, qui ont permis d’établir le référentiel, les échantillons complexes constitués de l’eau de lavage des baies de raisins, ont été analysés. Ainsi, nous avons pu analyser et différencier plusieurs parcelles de cépage chenin, situées dans des conditions pédoclimatiques différentes.

English version: Since the vintage wine 2002, a study is led on the variety of the fungal flora of parcels of the Chenin vine, situated essentially on the controlled origin label of Vouvray and Montlouis; two controlled origin label separated by the river named the Loire. The parcels are situated in conditions different of soils and of climate, which meet through the follow-ups of maturity and the sanitary state.

The objective is to use the fungal flora as factor of differentiation between the parcels, and evolution during the maturity. It is in this frame that a tool of microbial ecology was used: Denaturing Gradient Gel Electrophoresis (DGGE). PCR-DGGE is a molecular method which allows the direct analysis of DNA in complex samples without any culture step. This method is based on the separation in a denaturing gradient of double-strand DNA fragments which have the same length but different nucleotide sequences. After a specific study on fungus of grapes, which allowed establishing the reference table, the complex samples constituted by some water of wash of the berries of grapes, were analyzed. This tool will allow us to draw a parallel between the dynamic of fungal populations present in different conditions of soil and of climate. PCR-DGGE showed its potentialities for a fast characterization of fungi in complex mixes.

DOI:

Publication date: October 8, 2020

Issue: Terroir 2010

Type: Article

Authors

L. Guérin (1), M.Bouix (2), P. Poupault (1), R. Laforgue (1), P. Mallier (3), A. Mallet (3), J. Dupont (4)

(1) IFV Tours, 46 avenue Gustave Eiffel, 37100 Tours, France
(2) AgroParistech, Département de microbiologie industrielle, 1 avenue des Olympiades, 91744 Massy Cedex, France
(3) Chambre d’Agriculture d’Indre et Loire, 38 rue Augustin Fresnel, 37170 Chambray les Tours, France
(4) Muséum National d’Histoire Naturelle, Département Systématique et Evolution – Mycologie, 75005 Paris Cedex 05, France

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IVES Conference Series | Terroir 2010

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