Exploring the regulatory role of the grapevine MIXTA homologue in cuticle formation and abiotic stress resilience

The trial was conducted in variety/rootstock Riesling/Kober 5 BB in the vineyard district of Vrsac. The vineyard was planted in 1996 on a south-facing slope, with rectangular type pruning of 3×1 m. The training system is of symmetric cordon type and mixed type pruning is practiced.

Dans la région des Coteaux du Layon, en Maine et Loire, l’effet terroir et son déterminisme sont étudiés dans le cadre de la production des vins liquoreux.
Ces vins sont le résultat d’une maturité poussée au delà de celle prévue par la nature afin de donner aux baies une teneur en sucre et en matière sèche très forte, pour mieux valoriser ces effets de la surmaturation, les baies sont récoltées selon la méthode des tries successives (Asselin et al, 1996). Ainsi, on ne récolte à chaque passage que les grains ayant atteint le niveau de concentration requis pour obtenir des vins à fort degré d’alcool avec des sucres résiduels.

Significant wine aroma can be formed from non-volatile precursors that are linked to sugars, including but not limited to grape-derived monoterpene and C13-norisoprenoid glycosides.

Merlot grapevine is the second wine cultivar most planted in the world and especially in the Bordeaux wine region. This cultivar has many advantages in producing high quality wine; however, in the last decade, climate change has increased the sugar concentration in berries at harvest and shortened the maturation cycle. If this has been up to now a great opportunity to improve wine quality profile, we are touching the tipping point. High sugar concentration at harvest induces high alcool content in wine which can negatively impact wine quality. There are many viticultural and oenological practices possible to limit this effect. In this study we focus on plant material through intra-varietal diversity of Merlot cultivar.

Red wine ageing impacts its chemical and sensory characteristics such as colour, astringency and aromas evolution. Wine ageing involves many chemicals and physico-chemical reactions. Oxygen has an important role in these evolutions, especially during bottle ageing. It is known that wine composition and its antioxidant capacity are correlated to its ability to undergo with oxygen exposure [1]. A high oxygen exposure can affect wine quality by the formation of undesirable oxidative volatile compounds such as acetaldehyde [2]. Thus, ageing capacity is an important factor for wine quality and is related to extent of oxidation with ageing [3].