Étude intégrée et allégée des terroirs viticoles en Anjou: caractérisation et zonage de l’unité terroir de base, en relation avec une enquête parcellaire

AIM This work aims to investigate fluorescence spectroscopy as a tool to assess grape homogenates to discriminate between samples of varying maturities and to develop an index to objectively characterise the level of grape heterogeneity present in any given vineyard.

The historical Tokaj region in northeast Hungary is a UNESCO World Heritage region since 2002 owning 5.500 ha vineyards. Produced from „noble rot” grapes, Tokaji Aszú is known as one of the oldest botrytized wines all over the world. Special microclimatic conditions (due to Bodrog and Tisza rivers, Indian summer), soil circumstances (clay, loess on volcanic bedrock) and grape-varieties (Furmint, Hárslevelű) of Tokaj-region offer favourable parameters to the formation of noble rot caused by Botrytis cinerea. The special metabolic activity of Botrytis results in noble rot grapes called “aszú” berries. The grapes undergo complex chemical modifications as the joint result of the enzymatic activity of Botrytis and the physical process of concentration.

Global grape production amounts to approximately 70 million tons per year, with Europe contributing 61% of the world’s wine output, primarily from Italy, France, and Spain.

The chemistry of wine oxidation is captured in the reactions between the oxidation products, mostly reactive electrophiles, with other wine constituents. An understanding of both components and their reactions can lead to ideas and techniques to control and mitigate or enhance these reactions to allow for the desired development of the wine. Current investigations are yielding much useful information about oxidation reactions in wine.

The year-on-year rise in temperatures and the increase in extreme weather events due to climate change are already having an impact on agriculture. Among the perennial fruit species, grapevine is already negatively impacted by these events through an acceleration of its phenology, more damage from late frosts or through an increase in the sugar level of the berries (and therefore the alcoholic degree of the wine) and a decrease of acidity, impacting the wine quality. Sun’Agri, in partnership with INRAE, Chambre d’agriculture du Vaucluse, Chambre d’agriculture des Pyrénées-Orientales and IFV, developed a protection system based on dynamic agrivoltaics to protect grapevine. It consists of photovoltaic solar panels positioned above the crop, high enough not to impede the passage of agricultural machinery, and tiltable from +/- 90° to adjust the level of shading on the vineyard. These smart louvers, driven by artificial intelligence (physical models & plant growth models), are steered according to the plant’s needs and provide real climate protection.