The aim of the thesis was to investigate the main differences and effects between organic, biodynamic, integrated and conventional grape production, in particular on the microbial biodiversity on the grape, especially on yeast communities and their effects on the fermentation process and success, as well as on the chemical conposition and sensory quality of the wine. Organic and biodynamic grape cultivation has the highest diversity of the yeasts on the grapes. In organic and biodynamic production, the greater diversity in the microbial community is due to the increased use of organic fertilisers, such as various cattle manures and various plant parts, and the limited number of various pesticides. The microbial community is also influenced by vineyard location, variety, insect biodiversity, climate, soil characteristics and the agrotechnical practises. Regardless of the type of grape production, non-Saccharomyces yeasts such as Hanseniaspora, Metschinikowia, Kluyveromyces, Candida and Pichia make up the majority of all wild yeasts present on grapes, and their abundance can be reduced by penconazole application and increased by grape contact with insects. The rate and progression of spontaneous fermentation depend on the presence of S. cerevisiae yeast strains. The organic production favours yeast species or genera with the enzymatic ability to convert precursors into active compounds, and consequently influences aromatic compounds in the wine. The type of grape production does not affect the chemical characteristics of the wine, but the wine from organic/biodynamic production is often sensorially more harmonious, with a pleasant flavour, a longer aftertaste and a more pronounced aroma and taste reminiscent of fruit, compared to wines from other grape productions.
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