Yeasts of the genus Saccharomyces were distinguished from the other isolates (from non-Saccharomyces species) by ITS-PCR-RFLP (the length of PCR amplicon was 880 bp). Further, for S. cerevisiae species identification we employed species-specific primers ScerF2 and ScerR2. 12 Species-specific primers enable us to identify and distinguish S. cerevisiae species from other species belonging to the Saccharomyces sensu stricto complex, which includes the species which can also be found in fermented must (for. ex. Saccharomyces bayanus, Saccharomyces pastorianus, Saccharomyces kudriavzevii). Based on our results, all the isolates belonging to the Saccharomyces genus were identified by species-specific primers as S. cerevisiae (the length of the PCR products was 150 bp) (data not shown).
Further, two different PCR-assays by using M13 primer were used. These assays differed in annealing temperature (50 °C vs. 36 °C). The isolates were divided into three groups by the first assay with annealing temperature 50 °C and into four groups by the second PCR-assay (36 °C). Data are presented as part of the dendrogram (Fig. 1). Two isolates (marked as U, T) exhibited a different fingerprinting profile than the rest of the isolates; these isolates may be hybrids of S. cerevisiae and another species belonging to the Saccharomyces genus. Hence, PCR-fingerprinting techniques using M13 primer are able to group the species members of Saccharomyces genus but they are not suitable for resolving