Decline of rootstock-mediated physiological responses in Tempranillo grapevines by prolonged extreme conditions

Following the latest oiv global report (april 26, 2024), the prevailing perception of wine consumption finds itself undergoing one of its most challenging adjustments. It’s plausible to anticipate a shift in the scope of pdo wines towards more human-centered products (wells and stiefel, 2019), necessitating the entire sector to adapt strategies to public interest patterns (touzeau, 2010: 17-31). Previously, a dominant notion of cultural property underscored the value of wine regions; the primary interest revolved around estate owners and retailers, along with vigneron tales.

One of the major threats to viticulture is represented by fungal pathogens. Plasmopara viticola, an oomycete causing grapevine downy mildew, is one of the principal causes of grape production losses. The most efficient management strategies are represented by a combination of agronomical practices, fungicides’ applications, and use of resistant varieties. Plant resistance is conferred by the presence of resistance (R) genes. Opposed to them, susceptibility (S) genes are encoded by plants and exploited by pathogens to promote infection. Loss or mutation of S genes can limit the ability of pathogens to infect the host. By exploiting post-transcriptional gene silencing, known as RNA intereference (RNAi), it is possible to knock-down the expression of S genes, promoting plant resistance.

Nowadays, the rapid growth of vineyards with organic practices and the use of copper as the only fun-gicide against downy mildew raises again the question of the effect of copper on varietal thiols in wine, especially 3-sulfanylhexan-1-ol (3SH) and its acetate (3SHA). A few decades ago, several works indicated that the use of copper in the vineyard had a negative effect on the content of varietal thiols in Sauvignon blanc wines [1, 2]. However, these studies only considered the concentration of the reduced form (RSH) of varietal thiols, without quantifying the oxidised ones. For this purpose, we proposed to monitor both reduced and oxidised forms of varietal thiols in wine under copper stress during alcoholic fermentation to have a more complete picture of the biological and chemical mechanisms.

In recent years, the consumption of alcoholic beverages is changing, driven by evolving consumer preferences and societal trends, including a wave of health consciousness. Among these changes, the emergence and proliferation of nolo (no alcohol/low alcohol) alcoholic beverages have gained significant attention within the industry. Nolo alcohol beverages are produced to emulate the appearance, aroma, and taste of alcoholic beverages, potentially facilitating a sense of social integration when consuming a product that closely resembles alcohol.

The blend of grapes used in the production of the four Valpolicella PDOs red wines, namely Valpolicella, Valpolicella Classico Superiore, Recioto della Valpolicella and Amarone della Valpolicella is quite unique, and includes two main varieties Corvina and Corvinone, and other minor varieties. To a very large extent all these grapes are only grown in the province of Verona. One of the main characteristics of Valpolicella is the use of grapes that are submitted to post-harvest withering. The aim of this study was therefore to evaluate the evolution of the free and glycosidically-bound volatile compounds in Corvina and Corvinone grapes under real production conditions.