S_allele identification and genetic diversity analysis of apricot cultivars

In this study, the sexual incompatibility and S-allele diversity of 24 Turkish apricot cultivars, Paviot and Sak?t-1 as parents and 127 F₁ progenies were identified by polymerase chain reaction (PCR) and sequencing techniques. Additionally, genetic diversity and relatedness among the 24 cultivars were determined using 18 simple sequence repeat (SSR) markers from the genus Prunus. PCR for S_alleles identified nine different S-RNase alleles in the 24 apricot cultivars, namely S_c, S₁, S₂, S₈, S₉, S₂₀, S₂₄, S₅₂, and S₅₃. All primers amplified only one S_allele in the cultivars Adilcevaz-1, Adilcevaz-3, Ethembey, Pasamismisi, Canakkale, and Soganci. Most of the Turkish cultivars were self-incompatible. The S_c allele was present in only three cultivars (Canakkale, Ethembey, Imrahor) that are, therefore, self-compatible. The S_alleles of cultivars Paviot and Sak?t-1 displayed homology with the S_c, S₂ and S₂₀, and S₅₂ alleles. In the 127 F₁ genotypes, the two S_alleles of Paviot were inherited by roughly half of the offspring, while about 76% of the offspring inherited the S₅₂ allele from Sak?t-1, and less than 24% inherited S₂₀. The amplification using all SSR 18 primers was successful and produced 128 polymorphic alleles with an average of 7.11 alleles per locus. Among the apricot cultivars studied, expected heterozygosity (He) ranged from 0.33 to 0.72, observed heterozygosity (Ho) ranged from 0.42 to 1.00, PIC values were between 0.28 and 0.89, and similarity rates were between 0.30 and 0.68. The cultivars Levent and Ozal were genetically closest (0.68) while cultivars Sak?t-3 and Soganc? were the most distinct (0.30).