Postveraison shoot trimming in Tannat and Merlot: preliminary results on yield components, plant balance and berry composition

Context and purpose of the study. Climate change is already threatening California vineyards, as they grapple with increasing extreme weather events and drier growing seasons.

Historical phenology records have indicated that advances in key developmental stages such as budburst, flowering and veraison are linked to increasing temperature caused by climate change. Using phenological models the timing of grapevine development in response to temperature can be characterized and projected in response to future climate scenarios.
We explore the development and use of grapevine phenological models and highlight several applications of models to characterize the timing of key stages of development of varieties, within and between regions, and the result of projections under different climate change scenarios.

Champagne or sparkling wines elaborated through the same traditional method, which consists in two major yeast-fermented steps, typically hold about 10 to 12 g/L of dissolved CO2 after the second fermentation in a closed bottle. Hundreds of molecules and macromolecules originating from grape and yeast cohabit with dissolved CO2; they are essential compounds contributing to many organoleptic characteristics (effervescence, foam, aroma, taste, colour…). Indeed, the second alcoholic fermentation and the maturation on lees (which may last from 12 months up to several years) both induce various quantitative and qualitative changes in the wine through the action of yeast, as listed hereafter: development of aromas during aging on lees, release of nitrogen compounds during autolysis and release of macromolecules (polysaccharides, lipids, nucleic acids) in wine.

Long-term use of copper fungicides causes increased accumulation of total copper in the surface layer of vineyard soils. Many of authors has researched the anthropogenic influx of copper in such soils, which can result in environmental risks.

It is known that high temperature influences the synthesis, transformation and degradation of grape anthocyanin (ANT) threatening the quality of grapes and coloured wines.