Viticultural climate effect on the sensorial perception of wines. Methodological elements for a modelling at a world level

Grapevine cultivation is threatened by the global warming, which combines high temperatures and reduced rainfall, impacting in wine quality and even plant survival. Breeding for varieties resilient to these challenges must address plant traits such as tolerance to supraoptimal temperatures and optimized water use efficiency while minimizing productivity and quality losses. Stomatal abundance (SA) determines the maximum leaf potential for transpiration and thus water loss and cooling. Since SA results from a developmental process during leaf emergence and growth, knowledge on the genetic control of this process would provide specific targets for modification.

Context and Purpose of the Study. A deeper understanding of the relationship between weather conditions and wine quality is essential for assessing the impact of climate change and developing effective adaptation strategies.

The sequential activity of miR156 and miR172 controls the juvenile to adult phase transition in many plant species, where miR156 abundance decreases while miR172 increases along plant development. Very little is known about phase transition in horticultural woody species, which show substantially long vegetative phases. In grapevine, phase transition seems to be dissociated, displaying a first transition from juvenile to adult vegetative state in the first year, coincident with tendril differentiation and a subsequent induction of inflorescences in place of some of tendrils in later years under flowering inductive environmental conditions. Since grapevine is a highly heterozygous species, the generation of genetically homogeneous material for replicated transcriptomic analyses from seed-derived plants was a main challenge.

Temperature extremes affect grapevine physiology, as well as grape quality and production. In most grape growing regions, frost or heat wave events are rare and as such conducting a risk analysis using robust statistics makes the use of long term daily data necessary.

The last step in winemaking is packaging the wines for market placement, while preserving the quality attained during vinification. Since the 1980s, 2,4,6-trichloroanisole (TCA) has been recognised as an incidental and random contaminant of cork, with its migration into wine thought to contribute to ‘cork taint’. This molecule is not a cork component and little is known about how it is formed on trees. Its formation from the chlorine used to wash the cork stoppers, long suspected, has been excluded by the abandonment of chlorine washing.