Exploring relationships among grapevine chemical and physiological parameters and mycobiome composition under drought stress

Brettanomyces is a world-renowned yeast that negatively impacts the chemical composition of wines through the production of metabolites that negatively impact the sensory properties of the final product. Its resilience in wine conditions and ability to produce off-flavors make it a challenge for winemakers. Currently, the primary control technique involves adding sulfur dioxide (SO2); however, some Brettanomyces strains are developing resistance to this preservative agent. [1] Therefore, new management strategies are necessary to control this spoilage yeast.

The O2 uptake in the different winemaking processes is generally considered to be negative for the sensory characteristics of white and rosé wines. Wine racking is a critical point of O2 uptake, as the large surface area of the wine exposed during this operation and the inability to maintain an effective inert gas blanket over it.
The objective was to study O2 uptake during the racking of a model wine without using inert gases and to compare it with the purging of the destination tank with different inert gases.

‘Tempranillo Tinto’ is a black-berried Iberian cultivar that originated from a hybridization between cvs. ‘Benedicto’ and ‘Albillo Mayor’ [1]. Today, it is the third most widely grown wine grape cultivar worldwide with more than 200,000 hectares of vineyards mostly distributed along the Iberian Peninsula, where it is also known as ‘Cencibel’, ‘Tinta de Toro’, ‘Tinta Roriz’, and ‘Aragonez’, among other synonyms. Here, we quantified the intra-varietal genomic diversity in this cultivar through the study of 35 clones or ancient vines from seven different Iberian wine-making regions. A comparative analysis after Illumina whole-genome sequencing revealed the presence of 1,120 clonal single nucleotide variants (SNVs).

The Maule region hosts up to a third of the total area of vineyards in Chile, in an environment where ancient practices inherited from the colonial past coexist with modernity and dynamism that include technified irrigation and fine vines. In the dry land of Maule there is a viticulture that has subsisted with ancient vines and traditions transmitted over generations, and there is little clarity about the origin and classification of the Maule viticulture, giving rise to the use of different concepts as synonyms to describe the ancient, minority, patrimonial or Criollas vines. In order to characterize and protect the ancient material, we studied the genetic diversity of a territorial collection that covers 80% of the communes of the region, prioritizing plants established more than 40-60 years ago.

Climate emergency is going to affect the agricultural suistainability, wine grapes being probably one of the crops more sensitive to environmental constraints. In this context, mitigation strategies such as the revalorization of agricultural wastes are paramount to cope with the current challenges. The use of organic mulches has been reported to reduce soil water evaporation and improve vine water status, reduce soil erosion, and increase soil organic matter with little impact on berry quality. However, less is known about their effects on the microbiote of vineyards.