Analyse du rôle du terroir dans la définition d’une appellation d’origine

Rotundone accumulation and biosynthesis is a complicated process. Previous research highlighted that these phenomenons were affected under ecophysiological conditions by viticultural practices (e.g. defoliation or irrigation). Individually, these practices often impact several abiotic factors that are difficult to separate such as temperature, water or nitrogen status, or radiation. Such dissociation can be achieved under controlled environmental conditions using potted vines.

Ya en 1964 GIOVANNI DALMASSO et alii describiendo el Moscato bianco (12) ponían de manifiesto la dificultad realmente ardua en descubrir “si no todas, por lo menos las más importantes variedades que llevan el nombre de Moscateles

One of the main plant defence mechanisms is the Systemic Acquired Resistance (SAR) mediated by Salicylic Acid (SA). This is a heightened and broad-spectrum immune response initiated by the exposure to pathogens, inducing resistance not only in the infected site, but also throughout the entire plant. It was demonstrated that plant immune system can be regulated by two classes of SA receptors: NONEXPRESSOR OF PR GENES 1 (NPR1) and NPR1-LIKE PROTEIN 3 and 4 (NPR3/NPR4). While NPR1 is required for SA-induction followed by the expression of pathogenesis-related (PR) protein and resistance against pathogens, NPR3/NPR4 serve as transcriptional co-repressors of SA-responsive genes.

Downy and powdery mildew are major issues in grapevine cultivation, requiring many phytosanitary treatments to ensure yield and quality. Climatic changes are also challenging grape cultivation

Sulfites (SO2) addition during winemaking is a widespread practice worldwide. This addition is realized at different steps of the winemaking due to the antimicrobial and antioxidant capacity of SO2. In a context of understanding white wines oxidative stability, knowledge about the impact of SO2 on the wine molecular diversity, especially compounds involved in the antioxidant capacity of wine, appears to be very important. In recent years, some studies have shown that SO2 can react with a large number of wine compounds resulting in the formation of numerous adducts. The diversity of compounds involved is important including in particular pyruvic acid, 2-keto-glutaric acid, glyceraldehyde, sugar, phenolics compounds but also amino acids or peptides. Moreover Roullier-Gall et al. have shown using FT-ICR-MS analysis that the molecular composition of wines remains impacted by addition of SO2 to the must (0, 4 and 8 g/hL SO2), several years after winemaking. Indeed, wines made from protected must (8g/hL SO2) contain a larger diversity of CHOS and CHONS compounds than wines made from unprotected must (0 g/hL SO2). The study of the impact of glutathione addition on the sensory oxidative stability has further shown that CHOS and CHONS compounds (amino acids, aromatic compounds and peptides) are markers of the antioxidant metabolome of white wines. This suggests that CHOS and CHONS compounds arise from SO2 adducts formation but also from a protecting effect of SO2 on the antioxidant metabolome of white wines.