Influence on grape aroma of nitrogen compounds and elicitors foliar applications in vineyards

Mandilaria, a red grape variety indigenous to the Aegean islands, is well known for its robust tannins and pronounced astringency, which can challenge the palatability and marketability of its wines. The aim of this study was the reduction of astringency in wines made exclusively from mandilaria grapes through dehydrations practices and targeted winery applications.

Previous work from our laboratory has shown that both a purified toasted oak powder and extracts made from unoaked and oaked red wines influenced physiological parameters, metabolism and hepatic gene expression in high-fat fed C57/BL6J male mice (Luo et al., 2020).  Impacted pathways included glucose metabolism, liver fat accumulation, markers of chronic inflammation, and expression of the Gsta1 mRNA.  

An integrated terroir characterization is currently realized in the French northern vineyard: “Anjou”. The concept of Basic Terroir Unit (B.T.U.) and its associated ground model “Rock, Alteration, Alterite” are used in this characterization. This work is coupled to a viticultural survey, based on parcels.

The use of soil conservation practices in wine grape production is becoming common throughout the world in response to an increased awareness of the value of soil health to maintain crop productivity and environmental quality. However, little information is available on the meaning of soil health within a viticultural context, and what soil properties should be targeted to achieve both the agronomic and environmental goals of wine grape producers. Conservation practices lead to increases in soil organic matter which may improve soil water retention, and increase soil C content therefore constituting a potential avenue to adapt to droughts and sequester C. Well-known management practices such as the use of cover crops, compost or no-till, although effective, seem to result in highly variable outcomes in soil organic matter and other soil health indicators. This variability is likely associated to the application of the practices in different soils and climates. Thus, integration of soil health building practices needs a thorough understanding of their efficacy under different conditions. Furthermore, additions of soil organic matter could trigger emissions of CO2 and N2O, a potent greenhouse gas that could represent a potential tradeoff of soil conservation practices. Finally, nutrient and water availability may be affected by the increase in soil organic matter having consequences for vine balance and grape quality.

La société et l’état imposent plus que jamais à la viticulture française de prendre en compte ses impacts environnementaux tout en produisant des vins de qualité. Après avoir présenté ces impacts, les auteurs exposent la méthode de l’Analyse du Cycle de Vie. Ils proposent une démarche pour sa mise au point pour évaluer les impacts environnementaux en viticulture AOP en Val de Loire dans le cadre de l’évaluation de la compatibilité des objectifs qualitatifs et environnementaux de la production de raisins de cuve.