Unravel the underlying mechanisms of delaying ripening techniques in grapevine

The Cognac region is expanding, driven by the success of its renowned brandy and the demand for high grape yields to ensure a steady supply of base wine for distillation. Ugni blanc, the most widely planted grape variety, relies on rootstocks for soil and climate adaptation, providing essential nutrient supplies to the scion. Understanding the impact of rootstocks on key berry components, such as sugars and nitrogen compounds, is crucial. These compounds serve as primary precursors for the production of fermentative aroma metabolites, which, in turn, act as quality indicators for eau-de-vie.

Grapevine cultivars are vegetatively propagated to preserve their varietal characteristics. However, spontaneous somatic variations that occur and are maintained during cycles of vegetative growth offer opportunities for the natural improvement of traditional grape cultivars. One advantageous trait for winegrowing is reduced bunch compactness, which decreases the susceptibility to pests and fungal diseases and favor an even berry ripening.

In recent years, a pool of terpenoids possibly implicated in minty odours and in the appreciable refreshing sensation, has been identified in long aged red Bordeaux wines (Lisanti et al., 2021, Picard et al., 2016; Picard et al., 2017). These compounds were found to play a key role in the so-called “ageing bouquet”, that can be defined as “the homogeneous, harmonious flavour resulting from the complex transformation process in wine during bottle storage” (Picard et al., 2015). Moreover the minty-fresh sensory dimension in fine aged red wines plays an important role in typicity judgement by wine professionals (Picard et al., 2015).

In this video recording of the IVES science meeting 2025, Marie Le Scanff (University of Bordeaux, UMR 1366 Oenologie, Institut des Sciences de la Vigne et du Vin, Villenave d’Ornon, France) speaks about the sensory contribution of grape stems during winemaking and about the role of astilbin, a sweet polyphenol. This presentation is based on an original article accessible for free on OENO One and on a technical article published on IVES Technical Reviews.

The effect of two rootstocks of different drought tolerance (1103 Paulsen and 3309 Couderc) on sap flow, water relations and gas exchange of cv. Xinomavro (Vitis vinifera L.) was investigated during the 2005 season in Naoussa, Greece. Soil was maintained at field capacity for both rootstock treatments until mid July when a restricted water regime was applied by irrigation cutoff. Sap flow diurnals for the Xinomavro-1103P combination showed a rapid decrease of flow after midday, under water stress conditions.