Terroir 1996 banner
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

Contact the authors

Keywords

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

Tags

IVES Conference Series | Terroir 2000

Citation

Related articles…

Downscaling of remote sensing time series: thermal zone classification approach in Gironde region

In viticulture, the challenges of local climate modelling are multiple: taking into account the local environment, fine temporal and spatial scales, reliable time series of climate data, ease of implementation and reproducibility of the method. At the local scale, recent studies have demonstrated the contribution of spatialization methods for ground-based climate observation data considering topographic factors such as altitude, slope, aspect, and geographic coordinates (Le Roux et al, 2017; De Rességuier et al, 2020). However, these studies have shown questions in terms of the reproducibility and sustainability of this type of climate study. In this context, we evaluated the potential of MODIS thermal satellite images validated with ground-based climate data (Morin et al, 2020). Previous studies have been encouraging, but questions remain to be explored at the regional scale, particularly in the dynamics of the massive use of bioclimatic indices to classify the climate of wine regions. The results at the local scale were encouraging, but this approach was tested in the current study at the regional scale. Several objectives were set: 1) to evaluate the downscaling method for land surface temperature time series, 2) to identify regional thermal structure variations. We used weekly minimum and maximum surface temperature time series acquired by MODIS satellites at a spatial resolution of 1000 m and downscaled at 500 m using topographical variables. Two types of analyses were performed:

Short-term relationships between climate and grapevine trunk diseases in southern French vineyards

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Different soil types and relief influence the quality of Merlot grapes in a relatively small area in the Vipava Valley (Slovenia) in relation to the vine water status

Besides location and microclimatic conditions, soil plays an important role in the quality of grapes and wine. Soil properties influence…

Heatwaves and grapevine yield in the Douro region, crop model simulations

Heatwaves or extreme heat events can be particularly harmful to agriculture. Grapevines grown in the Douro winemaking region are particularly exposed to this threat, due to the specificities of the already warm and dry climatic conditions. Furthermore, climate change simulations point to an increase in the frequency of occurrence of these extreme heat events, therefore posing a major challenge to winegrowers in the Mediterranean type climates. The current study focuses on the application of the STICS crop model to assess the potential impacts of heatwaves in grapevine yields over the Douro valley winemaking region. For this purpose, STICS was applied to grapevines using high-resolution weather, soil and terrain datasets over the Douro. To assess the impact of heatwaves, the weather dataset (1989-2005) was artificially modified, generating periods with anomalously high temperatures (+5 ºC), at certain onset dates and with specific durations (from 5 to 9 days). The model was run with this modified weather dataset and results were compared to the original unmodified runs. The results show that heatwaves can have a very strong impact on grapevine yields, strongly depending on the onset dates and duration of the heatwaves. The highest negative impacts may result in a decrease in the yield by up to -35% in some regions. Despite some uncertainties inherent to the current modelling assessment, the present study highlights the negative impacts of heatwaves on viticultural yields in the Douro region, which is critical information for stakeholders within the winemaking sector for planning suitable adaptation measures.

Mapping and tracking canopy size with VitiCanopy

Understanding vineyard variability to target management strategies, apply inputs efficiently and deliver consistent grape quality to the winery is essential. However, despite inherent vineyard variability, the majority are managed as if they are uniform. VitiCanopy is a simple, grower-friendly tool for precision/digital viticulture that allows users to collect and interpret objective spatial information about vineyard performance. After four years of field and market research, an upgraded VitiCanopy has been created to achieve a more streamlined, technology-assisted vine monitoring tool that provides users with a set of superior new features, which could significantly improve the way users monitor their grapevines. These new features include:
• New user interface
• User authentication
• Batch analysis of multiple images
• Ease the learning curve through enhanced help features
• Reporting via the creation of colour maps that will allow users to assess the spatial differences in canopies within a vineyard.
Use-case examples are presented to demonstrate the quantification and mapping of vineyard variability through objective canopy measurements, ground-truthing of remotely sensed measurements, monitoring of crop conditions, implementation of disease and water management decisions as well as creating a history of each site to forecast quality. This intelligent tool allows users to manage grapevines and make informed management choices to achieve the desired production targets and remain profitable.