Parcours de découverte des terroirs viticoles

High power ultrasound has been recently recognized one of the most promising technologies in winemaking processes, especially after the recent OIV resolution, concerning the application of ultrasounds on crushed grapes to promote the extraction of skin compounds.

In France, one of INAO missions is to delimit the production area of the « Appellations d’origine contrôlées » (AOC). For wine AOC, the delimitation of plots allows for identifying plots of land that respond to technical criteria of the vine location, criteria adapted in every appellation. Some old delimitations AOC are not in adequacy with their territory. Indeed, in spite the existence of a politic aiming to protect production areas AOC, urbanization, road infrastructure or quarries occupy surfaces classified in AOC today.

The effects of anthropogenic activities on vineyard (different plant protections) and in winery
(pressing/clarification step, addition of sulfur dioxide) on fungal populations from grape to wine were studied. The studied anthropogenic activities modify the fungal diversity. Thus, lower biodiversity of grapes from organic modality was measured for the three vintages considered compared to biodiversity from ecophyto modality and conventional modality. The pressing / clarification steps strongly modify fungal populations and the influence of the winery flora is highlighted.

Water tolerance in plants is often associated with the accumulation of osmotic protectants, which are secondary metabolites that can help the plant to cope with water stress. One of the key osmotic protectants is a sugar called Raffinose, which is synthesized by a family of enzymes called Raffinose synthases. In this work, we focused on one of these enzymes, VviRAF2, which is a gene that shows different expression levels and genetic variants (SNPs) among different grapevine cultivars, ranging from tolerant to susceptible to water stress, and the transcription factors that may regulate the expression of this gene family.

In this audio recording of the IVES science meeting 2022, Florence Fontaine (Université de Reims Champagne Ardenne) speaks about grapevine trunk disease. This presentation is based on an original article accessible for free on OENO One.