Characterization of different clone candidates of xinomavro according to their phenolic composition

Global warming and increased frequency and/or severity of drought events are among the most threatening consequences of climate change for agricultural crops. In response to drought, grapevine (as many other plants) exhibits osmotic adjustment through active accumulation of osmolytes which in turn shift the leaf turgor loss point (TLP) to more negative values, allowing to maintain stomata opened at lower water potentials1. We investigated the capacity of Pinot noir leaves to modulate their osmotic potential as a function of: (i) time (seasonal osmoregulation), (ii) growing temperatures, and (iii) drought events, to enhance comprehension of the resilience of grapevines in drought conditions. We performed trails under semi-controlled field conditions, and in two different greenhouse chambers (20/15 °C vs 25/20 °C day/night). For two consecutive vegetative seasons, grafted potted grapevines (Pinot noir/SO4) were subjected to two different water regimes for at least 30 days: well-watered (WW) and water deficit (WD).

Grapevine breeding is part of the research program of Agroscope in Switzerland since 1965. From 1965 to 1995, the aim of the Vitis vinifera crosses was to obtain a high resistance to grey rot (Botrytis cinerea), one of the most virulent fungal pathogens in the Swiss vineyard. In 2021, the grape varieties released from this first breeding program covered 936 ha of the 15’000 ha of the Swiss vineyard.
In 1996, a second breeding program aimed at obtaining, by classical interspecific hybridization, grape varieties resistant to downy mildew (Plasmopara viticola) and powdery mildew (Erisyphe necator) and less sensitive to grey rot (Botrytis cinerea). In order to accelerate and make the selection process more reliable, an early biochemical test was developed based on the natural defense mechanisms of the vine against downy mildew (stilbene phytoalexins). The synthesis of stilbenes (i.e., resveratrol and its oxidized dimers - and -viniférine) and pterostilbenes (methylated derivative) is among the most efficient induced defense mechanisms of grapevine against fungal pathogens on both the leaves and the clusters.

Le marché international du vin est désormais tourné vers la qualité et les vignobles de vin de masse se transforment pour construire la qualité et la réputation de leurs produits. Cette construction s’appuie notamment sur la valorisation de ressources territoriales de nature physique (terroir, pacage, écosystème) et humaine (savoir-faire, culture, patrimoine…). Les « Routes des Vins » sont des exemples concrets de ces processus de «territorialisation», combinant ces ressources territoriales pour communiquer sur l’ancrage géographique et la spécificité des vins. Les «Routes des Vins» émergentes, observées dans les régions vitivinicoles en transition vers la qualité, en Languedoc Roussillon, à Mendoza (Argentine) et au Western Cape (Afrique du Sud), participent souvent à la valorisation des terroirs, en organisant un itinéraire sur le territoire associé, en faisant découvrir les vins «de qualité», les paysages, les pratiques et le savoir-faire associés à leur élaboration.

This project aims on monitoring the plant development and comparison of the effects of various training systems on vine fertility and physiological processes.

Background: The Flavan-3-ol extraction from grape skin and seed during red-winemaking and their retention into wines depend on many factors, some of which are modified in the winemaking of blend wines. Recent research shows that Marselan, have grapes with high proportion of skins with high concentrations of flavanols, but produces red-wines with low proportion of skin derived flavanols, differently to the observed in Syrah or Tannat. But the factors explaining these differences are not yet understood.