Changes in flavonol profile are a reliable indicator to assess the exposure of red grape berries to solar radiation and canopy architecture

A partir des recherches conduites sur la caractérisation des terroirs viticoles par des chercheurs de l’Unité de Recherches Vigne et Vin (1, 2, 3, 4, 5) du Centre INRA d’Angers, Terre des Sciences, le Centre de Culture Scientifique et Technique d’Angers (CCSTA) a mis au point un parcours de découverte d’une journée dans le vignoble angevin avec une approche pluridisciplinaire.

Challenges associated with climate change, such as soil erosion and drought, have impacted viticulture across wine regions globally in recent decades. As winegrowers struggle to maintain yield and quality standards under these conditions, methods to adapt to and mitigate the impacts of climate change have become more prevalent. One potential mitigation strategy is to enhance symbiotic interaction of grapevine roots with arbuscular mycorrhizal fungi (AMF).

Extension of the growing season, compression of the annual growth cycle and higher frequency and severity of weather extreme events are consistent features of global warming. While mitigation of factors causing global warming is necessary in the medium-long term, wine growers need “ready to go” adaptation practices to counteract negative effects bound to climate change. This must be done in a sustainably way, meaning that remunerative yield, desired grape quality, low production cost and environment friendly solutions must be effectively merged. In this work, we will review contribution given over the last two decades prioritizing issues related to scion and rootstock choice, changes in vineyard floor management, new perception related to the use of irrigation in vineyards, adaptation practices aimed at decompress maturity, solutions to counteract or minimize damages due to late frost and sunburn and, lastly, some hints on how precision viticulture can help with all of this.

Context and purpose. The vine is a holobiont, where the plant interacts positively, negatively, and neutrally with microbes that together form the vine’s microbiome.

A trend to reduce chemical inputs in wines exists, especially sulfur dioxide (SO2). This additive is widely used due to its antioxidant, antiseptic and antioxidasic properties. During without sulfites vinification, bioprotection by adding yeast on harvest could be a sulfites alternative. With extension of this wine market, sensory impact linked to sulfites absence and/or sulfites alternative should be evaluated. That’s what this approach proposes to do, focusing on sensory characteristics of wines produced with or without SO2 addition during the winemaking process. METHODS: Wines were elaborated from Merlot grapes of two maturity levels according to three modalities: SO2, without SO2 and bioprotection on harvest (mix of Torulaspora delbrueckii and Metschnikowia pulcherrima). SO2 modality was sulfited throughout the winemaking and aging processes whether other modalities received any addition. After two years of aging, sensory studies were carried out with a specific panel for one month. First, descriptors were generated to differentiate the wines, then panelists were trained on these specific descriptors for five sessions and finally wines sensory profiles were elaborated