The S-genotyping of wild-grown apricots reveals only self-incompatible accessions in the Erzincan region of Turkey

The S-genotypes of 63 wild-growing Turkish apricots (Prunus armeniaca L.) were determined by PCR amplification of the S-RNase intron regions and SFB gene in order to characterise their sexual (in) compatibility phenotype. We determined the complete S-genotype of 63 wild-grown apricot accessions that originated in the Erzincan region. Ten previously described and 2 new S-alleles (provisionally labelled S-X and S-Y) were identified in the genotypes. S-2 was the most frequent S-allele in the tested germplasm (occurred in 19 accessions), followed by S-8 (17), S-19 (16), S-3 (13), S-12 (11), S-6 (10), and S-7 (10); while S-9-, S-11-, and S-13-alleles were found in 8 accessions. A total of 36 different S-genotypes were assigned to the tested accessions. The S-C-allele responsible for self-compatibility in apricot was not present, indicating that all accessions are self-incompatible. The analysis of S-allele frequencies allowed us to conclude the close relationship of wild-grown and cultivated apricots in Turkey and helped to raise hypotheses to explain high occurrences of S-2- and S-8-alleles.