Food Science

Research Organisation Partners

• Agricultural institute of Slovenia  
• Jožef Stefan Institute

Abstract

The climate is changing rapidly, and this change, along with habitat destruction and the use of agricultural chemicals, poses a major threat to global biodiversity. Just like a plant or higher animal, a microbial species can disappear due to changes in climate or are displaced by an invading non- native species. Winemaking is a traditional Slovenian fermentative technology that relies on complex microbial communities on the surfaces of grape berries. The predominant yeasts of grape berry communities are wine yeasts of the genus Hanseniaspora, which have a strong impact on wine quality through the production of volatile compounds, and play a vital role in the nutritional ecology of Drosophila species in vineyards. However, in line with global warming and global trade, a destructive fruit fly pest, D. suzukii, has invaded Slovenian vineyards and caused enormous economic damage. At the same time, we have detected an invasion of non-native species of Hanseniaspora opuntiae in Slovenian vineyards. From genomic data, it is now possible to infer environmental influences and evolutionary drivers on the species we know today and to understand the nature of adaptation of these invasive species to the human-made ecosystem. This project aims to determine the population structure of invasive in comparison to autochthonous wine yeasts and correlate it to their symbiotic relationship with an invasive fruit fly D. suzukii. Furthermore, we will investigate mode of adaptations of invasive microbial species to novel man-made environments in context of their genomic and phenotypic plasticity. Finally, to reconstruct past genetic adaptations to human-induced environmental stresses, we will simulate experimental adaptive evolution under laboratory settings. The combined application of detailed intraspecies variations on genomic and phenotypic levels represent a new approach in the field of wine production, and this will provide unprecedented insight into the impact of climate change on terroir signature of the wine.

The phases of the project and their realization

WP1    Evaluation of displacement of autochthonous wine yeasts by thermotolerant yeasts in Slovenian vineyards by the invasive fruit fly

Deliverables: The work package will result in a collection of representative autochthonous and non-residential yeast strains from Slovenian vineyards on the basis of which we will be able to define the degree of replacement of autochthonous wine yeast by the non-residential species, and to define their vector for dispersal and symbiotic relationships.

WP2    Revealing adaptation to wine-making environments with population genomics

Deliverables: The goal is to create a full-length chromosome map of reference strains to establish a population structure of invasive/autochthonous strains, and to identify genetic signatures that distinguish isolates adapted to man-made environmental changes from wild strains, as well as to provide a comprehensive overview of phenotypic traits associated with successful adaptation to environmental change.

WP3    Reconstruction of adaptive evolution under laboratory settings

Deliverables: A model of the adaptive processes to simple pressures in wine yeast that will give a general overview on the novel microbial species that invade traditional technologies due to climate change.

WP4 Impact of non-residential wine yeasts on wine terroir

Deliverables: Assessment of changes in wine yeast microbiota in vineyards on terroir signature to wine