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IVES 9 IVES Conference Series 9 Les propriétés de réflectance du sol de la parcelle sont à considerer comme des paramètres du terroir

Les propriétés de réflectance du sol de la parcelle sont à considerer comme des paramètres du terroir

Abstract

Suite à des expérimentations de solarisation artificielle réalisées en 1999 en conditions réelles de culture, à partir de matériels réfléchissants partiellement colorés en vert, en bleu, ou en rouge, on démontre que la sollicitation de la vigne par une réflexion rouge (vers 670 nm) est significativement plus efficace que toute autre réflexion colorée pour améliorer la qualité des raisins à la récolte, celle-ci étant jugée à la fois à partir des analyses biochimiques et à partir des dégustations. Les raisins “solarisés” en environnement lumineux rouge sont plus gros, plus sucrés, un peu moins acides et plus réguliers en taille et en couleur. Par ailleurs, dans le cas des raisins de table, la couleur des baies et le rendement commercial après tri sont significativement améliorés.
Les résultats suggèrent fortement que les propriétés optiques et spectrales (la réflectance) de la surface du sol de la parcelle (et aussi de l’environnement général de la souche) doivent, de la même façon que les revêtements de solarisation, influencer le développement et la qualité des raisins. Ces propriétés devraient être prises en compte dans les explications de l’effet terroir.
Aux niveaux physiologique et moléculaire, les auteurs considèrent que les effets bénéfiques liés à la lumière rouge doivent être spécifiquement médiatisés par l’équipement phytochromique de la vigne

DOI:

Publication date: February 24, 2022

Issue: Terroir 2000

Type: Article

Authors

François-Xavier SAUVAGE**, Marc CHOVELON* and Jean-Pierre ROBIN**

*Sica ‘La Tapy’, 84200 Serres-Carpentras
**INRA Laboratoire de Biochimie Métabolique et Technologie, Institut des Produits de la Vigne, 2 Place Viala, 34060 Montpellier Cedex 1

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Keywords

vigne, raisin, terroir, sol, réflectance, lumière, solarisation

Tags

IVES Conference Series | Terroir 2000

Citation

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