Comportement hydrique des sols viticoles et leur influence sur le terroir

Wines made with grapes submitted to postharvest dehydration are often referred to as “passito” or “straw wines.” This distinct style of winemaking consists of a process of water loss that allows the berries to undergo a mild water stress and senescence process [1].

In winemaking, the appearance of turbidity in white and wine is a serious visual defect, which lowers significantly its commercial value. A major cause of the formation of turbidity in wine is attributed to the presence of temperature-sensitive proteins.

Fruity aromas, characterized by red and black fruit descriptors, are central to the identity of Bordeaux red wines [1,2]. Despite extensive research focused on identifying and quantifying volatile compounds that contribute to fruity aromas in wine, the mechanisms underlying their interactions and sensory perception remain poorly understood [3].

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:

to maintain viticulture under global warming conditions, it is important to carefully select the appropriate genotypes for each vine-growing region and develop cultivars that are drought resistant. this ability is highly dependent on hydraulic traits, which are dynamic and vary according to the vine’s developmental stage and climatic conditions. this framework steadily enhances our understanding of the differences in drought resistance among vitis genotypes. however, there is still a need to comprehensively grasp the intra-specific variability, particularly between oenological and table grape cultivars.