Utilizing ozone for the management of powdery mildew (Erysiphe necator Schwein.) in vineyards: potential and challenges

Understanding grapevine molecular processes and the underlying defence responses is vital for developing sustainable disease control strategies. Lipid signalling pathways, involving the synthesis and degradation of lipid molecules, have emerged as a key regulator in plant defence against pathogens. This study aims to elucidate the role of fatty acids and lipid signalling in grapevine’s defence response to P. viticola infection. The expression of lipid metabolism-related as well as lipid signalling genes was analysed, by qPCR, in three grapevine genotypes: Chardonnay (susceptible), Regent (tolerant) with Rpv3-1 resistance loci, and Sauvignac (resistant) harbouring a pyramid of Rpv12 and Rpv3-1 resistance loci.

Considerable advances have been made in the chemical characterization of wine metabolites through its holistic study using both targeted and untargeted metabolomics approach. The metabolite pool is subject to an intense molecular dialogue which reinforces the wine complexity even after bottling.

The selection, characterization, and recruitment of autochthonous yeast strains to drive the alcoholic fermentation process is a highly researched practice because it allows the differentiation of the organoleptic properties of wines, assuring process standardization, reducing fermentation times and improving the quality and safety of the final products [1, 2]. Sparkling wines are “special wines” obtained by secondary fermentation of the base wine. ​In the traditional method (Champenoise method), the re-fermentation takes place in the bottle after the addition to the base wine of the so-called tirage solution. This step, also known as prise de mousse, is followed by an aging period characterized by the release of compounds from the yeast cells that affect the organoleptic properties of the final product. The use of autochthonous yeasts as starter cultures for secondary fermentation is one of the recent innovations proposed to enhance and differentiate these wines’ sensory quality [3,4]. Apulia is the second Italian wine-producing region, and its productive chain is now going through a qualitative evolution by implementing the employment of innovative approaches to exalt the peculiar properties of regional wines.

In the study of terroir, a separate analysis of its many component factors can be of great help in accurately identifying a vineyard’s natural elements that impact wine quality and typicity. This research used a dedicated pluri-disciplinary approach to investigate the ecological characteristics, including geology and geographical features, of 14 vineyards that produce Gewürztraminer and Sauvignon Blanc cultivars in the alpine Alto Adige DOC wine region. Both the geopedological method using Vineyards Geological Identity (VGI) and the new Solar Radiaton Identity (SRI) topoclimatic classification method were used to provide analytical measurements and qualitative/quantitative characterisations. In addition, wide-ranging targeted and untargeted oenological and chemical analyses were carried out on grapes, musts and wines to correlate the soils’ geomineral and physical conditions with the biochemical properties of their fruits and wines. The research identified strong correlations between vineyard geo-identity and wine biofingerprint, confirming a mineral traceability of strontium rubidium ratio and some minerals distinctive to the local geology, such as K, Ca, Ag, Ba and Mn.  The study also discovered that particular geomineral and physical soil conditions of the studied vineyards are related to the different amount of amino acids, primary varietal aromas and polyphenols found in grapes, musts and wines. The research confirmed that winemaking technologies support oenological quality, although in some cases, human practices can overpower certain characteristic elements in wine, erasing the typical imprint left by the vineyards’ natural terroir, which becomes less traceable. Terroir abiotic ecological factors and vineyard identity can be classified in detail using the new VGI and SRI analysis methods to discover interrelationships between geo-pedological and topoclimatic conditions that impact wine quality. These methods are also helpful in identifying which ecological elements are exclusive to a particular vineyard or wine sub-region.

Climate is a key variable for grapevine development and berry ripening processes. At mesoscale level, climate spatial variations are often determined empirically, as weather station networks are generally not dense enough to account for local climate variations.