Impact of aging on dimethyl sulfide (DMS) in Corvina and Corvinone wines

Climate change is leading to an increase in average temperature and in the frequency and severity of heatwaves that is already significantly affecting grapevine phenology and berry composition (Webb et al., 2010). This is compounded by water stress, which is well known to increase the vulnerability of grapevines and berries to heatwaves. In hot climate regions like australia, grape production is only possible due to relatively secure supplies of water for irrigation. However, the upper temperature limits for berry survival of well-watered grapevines remains to be tested.

Le but de ce travail est de faire une synthèse des résultats de plusieurs années de recherche en Italie centrale, sur les caractéristiques fonctionnelles du sol pour la production de vin de qualité. Le cépage de référence est le Sangiovese

Kékfrankos (Vitis vinifera L.) grapevines grafted on Teleki-Kober 5BB rootstock were submitted to water deficit under greenhouse conditions.

Climate changes are impacting viticultural regions throughout the world with temperature increases being most prevalent.1 These changes will not only impact the regions capable of growing grapes, but also
the grapes that can be grown.2 As temperatures rise the growing degree days increase and with it the sugar accumulation within the berries and subsequent alcohol levels in wine. Consequently, viticultural
practices need to be examined to decrease the levels of sugars.

A pedological study was carried out from 2009 to 2017 in Beaujolais vineyard, to improve physical and chemical knowledge of soils. It was completed in 2016 and 2017 by the current study, dealing with microbial aspects, in order to build a reference frame for improved advice in soil management. Microbial biomass was measured on representative plots of the six most common soil types identified in Beaujolais and, for each soil type, on plots with different levels of the main impacting parameters: total organic carbon, pH, cation exchange capacity, extractable copper. A total of 59 soil samples were collected. Confirming the results of various trials carried out in Beaujolais over the past 20 years, the results of the present study showed that the soils were still alive, but exhibited a large variability of biological parameters, which appeared dependant on both pedological and anthropic factors. Therefore, a good interpretation of biological parameters and advice for vine growers must rely on a pedologically-based referential with differentiated main driving factors. For example, the control of pH is of primary importance in granitic soils and in no way organic matter addition can improve soil quality if pH is too low. Conversely, in calcareous soils, biological parameters are more directly affected by direct or indirect (cover crops for example) inputs of organic matter. The use of biological parameters, such as microbial biomass, is of great potential value to improve advice on agro-viticultural practices (soil management, fertilization, liming, etc.), basis of a sustainable wine production on fragile soils.