Identification of S-genotypes of sweet cherry cultivars from Central and Eastern Europe

Sweet cherry is a species that is characterized by self-incompatibility, which causes difficulties in obtaining high yields of sweet cherry fruit. Determination of the composition of the S-alleles of sweet cherry cultivars is useful both to growers producing the fruit and breeders when selecting cultivars for cross-fertilizations. In this work, S-alleles have been identified for 47 sweet cherry cultivars from Central and Eastern Europe, mostly from Ukraine and the Czech Republic, with S-genotypes of 43 cultivars identified for the first time. To identify the S-alleles, PCR-based methods were used. In each cultivar, two of the following eight S-alleles were identified: S1, S2, S3, S4, S5, S6, S9 and S13. In the cultivars from the Czech Republic, the most frequently occurring were the alleles S3, S1 and S4. In the cultivars originating in Ukraine, the most frequently found were the alleles S5 and S9, which makes them differ considerably from the sweet cherry cultivars from other regions of Europe. The tested sweet cherry cultivars were assigned to 20 of the existing incompatibility groups.