Rootstock influence on xylem embolized vulnerability and scion behavior under severe water deficit

When talking about terroir, scientists and lay wine tasters, very much including wine journalists and wine growers, too often talk past one another.

Climate change establishes challenges, as well as opportunities for many sectors, and markedly the wine sector.

Viticulture needs for spatial and temporal information are increasing to improve vineyard management, especially concerning water efficiency. Remote sensing, particularly from satellites, can be a powerful tool to assess vineyard characteristics such as vigor or water status in space-time. In this study, we use Landsat 8, an American Earth observation satellite with six bands from the visible (VIS) to the Short-Wave Infrared (SWIR) domains with 30m spatial resolution and two thermal bands with 100m spatial resolution.

Excell laboratory has initiated the development of an analytical method based on electrochemistry to evaluate the ability of wines to undergo or resist to oxidative phenomena. Electrochemistry is a powerful tool to probe reactions involving electron transfers and offers possibility of real-time measurements. In that context, the laboratory has implemented electrochemical analysis to assess oxidation state of different wine matrices but also in order to evaluate oxidative or reduced character of leaf and soil. Initially, our laboratory focused on dosage of compounds involved in responses of plant stresses and we were also interested in microbiological activity of soils. These analyses were compared with the measurement of redox potential (Eh) and pH which are two fundamental variables involved in the modulation of plant metabolism. Indeed, the variation of redox states of the plant reflects its biological activity but also its capacity to absorb nutriments. The Eh-pH conditions mainly determine metabolic processes involved in soil and leaf and our goal is to determine if this combined analytical approach will be sufficiently precise to detect biological evolutions (plant health, parasitic attack…).

One of the major determinants of wine quality is the aroma. Wine aroma is the human perception of the matrix of grape and yeast derived volatiles and their interaction that contribute to flavour wine. Most common are higher alcohols, ester and aldehydes. In previous studies the formation of characteristic volatile compounds have been linked to the metabolism of branched-chain and aromatic amino acids
(BCAAs) in synthetic grape must. Here we report on an investigation to assess the impact of the initial amino acid concentration on the production of aroma compounds by the industrial yeast VIN13 grown in both synthetic and real grape musts.