Determination of S-RNase genotypes and isolation of four novel S-RNase genes in Japanese apricot (Prunus mume Sieb. et Zucc.) native to China

Japanese apricot (Prunus mume Sieb. et Zucc.) originated in China with more than 500 cultivars. Most cultivars are self-incompatible. It is essential to identify S-genotypes for production and breeding. The S-genotypes of 17 Japanese apricot cultivars native to China were determined using the Prunus S-RNase consensus primer pair, Pru-C2 and PCE-R, which were designed from the second and third conserved regions of Prunus S-RNases, respectively. Eleven S-RNase alleles (S-1 S-2, S-7, S-12, S-14, S-15, S-18, S-20, S-22, S-23 and S-26) and four new S-RNase alleles (S-30, S-31, S-32 and S-33) with GenBank Accession Numbers JN232975, JN232976, JN232977, JN232978 were identified. Furthermore, the S-genotypes of four Japanese apricot cultivars were confirmed by field-testing for cross-pollination. The results of this study enrich the information available on S-genotypes in Japanese apricot and provide a reasonable basis for the appropriate arrangement of pollination trees in orchard practice.