Les motivations du vigneron en quête de l’expression “terroir”

La superficie actuelle de l’ensemble des vignobles est de 5.293 ha qui est repartie dans 27 communes (données officielles du Conseil National des Communes de montagnes).

Context and purpose of the study ‐ Vine balance is a concept describing the relationship between carbon assimilation (usually estimated using a measure of vine vigour, e.g. pruning weight) and its utilisation for fruit production (usually estimated using harvest yield). Manipulating vine balance through leaf area or crop load adjustments affects the proportion of the vine’s total carbohydrate production required to mature the fruit. It is commonly considered that composition of the berry, and resulting wine, is strongly affected by vine balance.

Enzymatic browning[1] is an oxidation process that occurs in many foods that increases the brown colour[2]. This problem is especially harmful in the wine industry[3]. especially when the grapes are infected by grey rot since this fung release the oxidative enzyme laccase[4]. In the particular case of red wines, the presence of laccase implies the deterioration of the red colour and can even cause the precipitation of the coloring matter (oxidasic haze)[5].

The plasticity of grapevines in response to diverse growing conditions is influenced, among other factors, by the extent to which the roots explore the soil and the ability to accumulate and retrieve water and nutrients.
Newly planted grapevines, in particular, face challenges due to limited resources. The young plant’s ability for a fast and intensive penetration of the soil is vital in periods of water scarcity. The selection of an appropriate, site-specific rootstock significantly impacts both, the quality of the fruit produced and the economic success of the wine estate.

Water tolerance in plants is often associated with the accumulation of osmotic protectants, which are secondary metabolites that can help the plant to cope with water stress. One of the key osmotic protectants is a sugar called Raffinose, which is synthesized by a family of enzymes called Raffinose synthases. In this work, we focused on one of these enzymes, VviRAF2, which is a gene that shows different expression levels and genetic variants (SNPs) among different grapevine cultivars, ranging from tolerant to susceptible to water stress, and the transcription factors that may regulate the expression of this gene family.