Déterminisme de l’effet terroir: influence de la surface foliaire primaire de la vigne en début de cycle sur le potentiel vendange

Prior to winemaking, organic or mineral nitrogen compound concentrations are usually measured in the vineyard and in grape musts. These indicators facilitate vine cultivation decisions, usually through yield or vigor. During vinification, yeast and bacteria metabolize nitrogen compounds in the musts in order to generate biomass. After fermentation, the microorganisms rerelease a part of this nitrogen as soluble compounds into the wines. Another part remains bound in the lees and can be lost during racking. The must’s natural nitrogen quantities, additional supplements during fermentation, and lees contact management enhance the release of nitrogen compounds to the wines. During ageing these nitrogen compounds – primarily the amino acids – are implicated in the generation of odorous compounds such as heterocycles(1).

Irrigation management is a critical aspect in grapevine cultivation to regularize grape production and quality in areas of clear water limitation.

The Muscadet area is situated in the southeast of Nantes, close to the Atlantic coast. It constitutes the western extension
of the French vineyard “Loire Valley”. The Muscadet is renowned and often spontaneously linked to a white wine.
However it remains misconceived as an ordinary wine, lacking authenticity.

In Franconia, the northern part of Bavaria in Germany, climate change, visible in earlier bud break, advanced flowering and earlier grape maturity, leads to a decrease of traditionally cultivated early ripening aromatic white wine varieties as Mueller-Thurgau (30 % of the wine growing area) and Bacchus (12 %). With the predicted rise of temperature in all European wine regions the conditions for white wine grape varieties will decline and the grapes themselves will lose a part of their aromatic and fruity expression. Variety change towards the cultivation of later ripening white wine varieties is a very expensive and long-term process, and must be accompanied by special marketing efforts.

Climate change and environmental degradation are existential threats to europe and the world. One of the most important objectives is to reduce by 2030 the use and the risk of chemical pesticides and fertilisers, reducing nutrient losses and increasing organic farming. Grapevine (vitis spp.) is one of the major and most economically important fruit crops worldwide. It is characterised by high levels of genetic diversity, as result of natural genetic mutations, which are common in grapevines and further assisted by ongoing vegetative propagation.