Flor yeast diversity and dynamics in biologically aged wines

We have sequenced two commercial strains of Lachancea thermotolerans (Lt) from the company Lallemand: Laktia™ y Blizz™.

A large varietal collection including over 1700 varieties was maintained in Conegliano, ITA, since the 1950s. Phenological data on a subset of 400 grape varieties including wine grapes, table grapes, and raisins were acquired at bud break, flowering, veraison, and ripening since 1964. Despite the efforts in maintaining and acquiring data over such an extensive collection, the data set has varying degrees of missing cases depending on the variety and the year. This is ubiquitous in phenology datasets with significant size and length. In this work, we evaluated four state-of-the-art methods to estimate missing values in this phenological series: k-Nearest Neighbour (kNN), Multivariate Imputation by Chained Equations (mice), MissForest, and Bidirectional Recurrent Imputation for Time Series (BRITS). For each phenological stage, we evaluated the performance of the methods in two ways. 1) On the full dataset, we randomly hold-out 10% of the true values for use as a test set and repeated the process 1000 times (Monte Carlo cross-validation). 2) On a reduced and almost complete subset of varieties, we varied the percentage of missing values from 10% to 70% by random deletion. In all cases, we evaluated the performance on the original values using normalized root mean squared error. For the full dataset we also obtained performance statistics by variety and by year. MissForest provided average errors of 17% (3 days) at budbreak, 14% (4 days) at flowering, 14.5% (7 days) at veraison, and 17% (3 days) at maturity. We completed the imputations of the Conegliano dataset, one of the world’s most extensive and varied phenological time series and a steppingstone for future climate change studies in grapes. The dataset is now ready for further analysis, and a rigorous evaluation of imputation errors is included.

In this video recording of the IVES science meeting 2024, Silvia Motta (Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria – Centro di Ricerca Viticoltura ed Enologia, Asti, Italy) speaks about the effect of SO2, glutathione and tannins on Cortese white wine oxidative evolution after different oxygen intakes. This presentation is based on an original article accessible for free on OENO One.

Dans de précédents travaux sur le zonage “GRANDE ZONAZIONE” (GZ) (“Grand Zonage”), on a traité, entre autre, de la “GRANDE FILIERA” (GF) (Grande filière) où parmi les 54 descripteurs prévus pour lire et évaluer par exemple un zonage, sont compris aussi la Communication

Dividing agrarian exploitations into microfields is a problem that influences the modern viticulture in a very important way. The aim of this work is the study of the influence of Geology and Geomorphology in agricultural structures