Varieties and rootstocks: an important mean for adaptation to terroir

Sustainable viticulture and winemaking continue to represent huge challenges, where a better knowledge about the functional role of biodiversity in the vineyard and wine ecosystems is required, as well as the varieties plasticity. Particular attention should be devoted to the spatial and temporal interactions between authorized or recommended varieties for a specific demarcated region and clime and vineyard conditions (such as soil type, orientation of the lines, age of the vine, density of planting, harvesting practices, among others).

Fermenting grape juice represents one of the oldest continuously maintained anthropogenic microbial environments and supports a well-mapped microbial ecosystem. Several yeast and bacterial species dominate this ecosystem, and some of these species are part of the globally most studied and best understood individual organisms. Detailed physiological, cellular and molecular data have been generated on these individual species and have helped elucidate complex evolutionary processes such as the domestication of wine yeast strains of the species Saccharomyces cerevisiae. These data support the notion that the wine making environment represents an ecological niche of significant evolutionary relevance. Taken together, the data suggest that the wine fermentation ecosystem is an excellent model to study fundamental questions about the working of microbial ecosystems and on the impact of biotic selection pressures on microbial ecosystem functioning. Indeed, and although well mapped, the rules and molecular mechanisms that govern the interactions between microbial species within this, and other, ecosystems remain underexplored. Here we present data derived from several converging approaches, including microbiome data of spontaneous fermentations, the population dynamics of constructed consortia, the application of biotic selection pressures in directed laboratory evolution, and the physiological and molecular analysis of pairwise and higher order interactions between yeast species. The data reveal the importance of cell wall-related elements in interspecies interactions and in evolutionary adaptation and suggest that predictive modelling and biotechnological control of the wine ecosystem during fermentation are promising strategies for wine making in future.

A major topic in viticultural research is the analysis of the relationships between climate on one side, and grape and wine quality on the other. It is well known that climatic conditions

The notion of terroir covers multiple components, from geology, pedology, geomorphology and climatology (Doledec, 1995), to aspects that are less well identified but which also intervene in the “typicality” of wines. This justifies the “zoning” approach (Moncomble and Panigaï, 1990) to define homogeneous areas, under the same agro-viticultural management and also identified at the product level (Morlat and Asselin, 1992).

S’il n’existe pas de réglementation officielle, la démarche des vins naturels prône un retour aux pratiques dites ancestrales préconisant notamment un mode d’élaboration des vins utilisant le moins d’intrants possible. Le seul autorisé reste l’anhydride sulfureux (SO2) à des doses quatre à cinq fois moins importantes que pour les vins dits conventionnels. Ce désir de renouer avec