Sensory differences of Pinot noir wines from willamette valley subregions

In this video recording of the IVES science meeting 2023, Hans Reiner Schultz (Hochschule Geisenheim University, Germany) speaks about soil carbon changes and greenhouse gas emissions in vineyards – is the 4 per 1000 goal realistic?. This presentation is based on an original article accessible for free on OENO One.

La création officielle du groupe Experts Zonage Vitivinicole à l’O.I.V., qui s’inscrit dans la Commission Viticulture, est récente. Le Professeur Mario FREGONI en assure la présidence depuis 1998, assisté du vice-président et du secrétaire général Mario FALCETTI. Ils ont été confirmés dans leurs fonctions lors des sessions de mars 2001. Actuellement, le groupe d’experts Zonage Vitivinicole de l’O.I.V. se compose de 40 délégués, représentant 18 pays membres. La mise en place de ce groupe a tout d’abord été initiée par l’Instituto Agrario de San Michele (Italie) et l’Unité de Recherches Vigne et Vin du Centre INRA d’Angers (France). Une collaboration entre les chercheurs s’est installée très tôt, dès 1987.

Context and purpose of the study. Berry sunburn in vineyards is a recurring disorder that can cause severe yield loss. As sunburn observations are often associated with heat waves, a link to climate change is likely.

Fermenting grape juice represents one of the oldest continuously maintained anthropogenic microbial environments and supports a well-mapped microbial ecosystem. Several yeast and bacterial species dominate this ecosystem, and some of these species are part of the globally most studied and best understood individual organisms. Detailed physiological, cellular and molecular data have been generated on these individual species and have helped elucidate complex evolutionary processes such as the domestication of wine yeast strains of the species Saccharomyces cerevisiae. These data support the notion that the wine making environment represents an ecological niche of significant evolutionary relevance. Taken together, the data suggest that the wine fermentation ecosystem is an excellent model to study fundamental questions about the working of microbial ecosystems and on the impact of biotic selection pressures on microbial ecosystem functioning. Indeed, and although well mapped, the rules and molecular mechanisms that govern the interactions between microbial species within this, and other, ecosystems remain underexplored. Here we present data derived from several converging approaches, including microbiome data of spontaneous fermentations, the population dynamics of constructed consortia, the application of biotic selection pressures in directed laboratory evolution, and the physiological and molecular analysis of pairwise and higher order interactions between yeast species. The data reveal the importance of cell wall-related elements in interspecies interactions and in evolutionary adaptation and suggest that predictive modelling and biotechnological control of the wine ecosystem during fermentation are promising strategies for wine making in future.

As elsewhere, southwestern France vineyards face more recurrent summer heat waves these last years. Among the possibilities of adaptation to this climate changing parameter, the use of net shading is a technique that allow for limiting canopy exposure to radiations. In this trial, we tested net shading installed on one face of the canopy, on a north-south row-oriented plot of cv. Gros Manseng trained on VSP system in the PDO Pacherenc-du-Vic-Bilh. The purpose was to characterize the effects on the ambient canopy temperatures and radiations during the season and to observe the consequences on the composition of grapes and wines. Two sorts of net were used with two levels of obstruction (50% and 75%) of the photosynthesis active radiation (PAR). They have been installed on the west side of the canopy and compared to a netless control. Temperature and PAR sensors registered hourly data during the season. On specific summer day (hot and sunny) manual measurements took also place on bunches (temperature) and in different spots of the canopy (PAR). The results showed that, on clear days, the radiation is lowered by the shade nets respecting the supplier criteria. The effects on the ambient canopy temperature were inconstant on this plot when we observed the data from the global period of shading between fruit set and harvest. However, during hot days (>30°C), the temperature in the canopy was reduced during afternoon and the temperature of the bunch surface was reduced as well comparing to the control. A decrease of the maturity parameters of the berries, sugar and acidity, was also observed. Concerning the wine aromatic potential, no differences clearly appeared.