Understanding the expression of gene families involved in anthocyanin biosynthesis during berry ripening: Tannat as a case study

L’A.O.C. Coteaux du Languedoc est située dans le Sud de la France, dans la partie Ouest de la bordure méditerranéenne. Elle forme un vaste amphithéâtre largement ouvert sur la mer méditerranée. L’Appellation a été constituée en 1960 par le regroupement de 14 anciennes petites appellations d’origine représentant 55 communes éparpillées dans les départements de l’Aude, de l’Hérault et du Gard. Par la suite, plusieurs extensions successives ont conduit à un ensemble actuellement composé de 168 communes.

Context and purpose of the study. Leaf osmotic adjustment (i.e., active accumulation of osmolytes in the cells) has been reported in grapevines in response to drought and as a natural process throughout the growing season (seasonal osmotic adjustment).

Increasing concentrations of greenhouse gases (GHGs) in the atmosphere due to human activities are leading to a rise in the average temperature of the atmosphere. among the scenarios established by the un’s intergovernmental panel on climate change (IPCC), only two enable us to achieve the minimum objective of the paris agreements signed at cop 21 in 2015: staying below +2°c after 2050. both scenarios forecast a rapid reduction in GHG emissions as early as 2025, thanks to strong international cooperation, the priority given to sustainable development and responsible consumer choices.

Viticulture worldwide is currently affected by the effects of climate change. This set of adverse phenomena lead to a deterioration of functional vine mechanisms, affecting growth, physiology and grape ripening, which may cause severe losses with respect to yield and quality. To prevent water stress and other abiotic factors from severely affecting its physiology, the vine’s response is to reduce transpiration and photosynthesis rates. This response varies depending on the cultivar and its ability to adapt to the environment. The hydroscape method is based on the internal regulation of water status in the plant. It has been recently used to classify grapevine genotypes according to their iso/anisohydric behavior when they are subjected to water stress conditions.

Climate change is challenging the resilience of grapevine, one of the most important crops worldwide. Adapting viticulture to a hotter and drier future will require a multifaceted approach that must include new management strategies, increased irrigation efficiency, and the identification of more drought tolerant genotypes.