Introduction: Malolactic fermentation (MLF) is a common process in winemaking to reduce wine acidity, maintain microbial stability and modify wine aroma. However, successful MLF is often hampered by their sluggish or stuck activity of malolactic bacteria (MLB) which may be caused by nutrient deficiency, especially when MLB are inoculated after alcoholic fermentation (Alexandre et al., 2004; Lerm et al., 2010). Identification and characterization of essential nutrients and growth factors for MLB allows for production of highly efficient nutrient supplements for MLF.

Genetic variants known to produce single residue missense mutations have been associated with phenotypic traits of commercial interest in grapevine. This is the case of the K284N substitution in VviDXS1 associated with muscat aroma, or the R197L in VviAGL11 causing stenospermocarpic seedless grapes. The impact of such mutations on protein structure, stability, dynamics, interactions, or functional mechanism can be studied by computational methods, including our pyDock scoring, previously developed. For this, knowledge on the 3D structure of the protein and its complexes with other proteins and biomolecules is required, but such knowledge is not available for virtually none of the proteins and complexes in grapevine.

The fruity aroma of red wines is described by a wide range of descriptors, ranging from fresh fruits to ripe and jammy fruits, to candied fruits and prunes notes [1]. The fruity quality of a red wine is characterized by notes of fresh and jammy red- and black-berry fruits.

In the current viticultural context, global warming leads to advanced and possibly accelerated ripening which can alter the balance among desirable grape quality traits sought for winemaking. Evaluation of genetic material that displays delayed and/or slower ripening could uncover a potential “slow ripening” trait for incorporation into commercial varieties through breeding. In this study, we evaluated a white-fruited selection discovered in the Grape Breeding and Genetics program at E. & J. Gallo Winery that displayed an unusual ripening pattern compared to standard varieties. Vines of the slow-ripening selection did not differ in their visual appearance, water status or gas exchange characteristics compared to vines of its normal-ripening sibling.

Le travail concerne en premier la méthodologie de caractérisation du climat des vignobles, à l’échelle du macroclimat des régions viticoles du monde (géoviticulture). Trois indices climatiques viticoles synthétiques