【Abstract】 Frozen young leaves of apricot(Armeniaca vulgaris) ‘Katy’ and ‘Xinshiji’ were used for isolation of total DNA. Total RNA was isolated from their styles at the balloon stage. DNA and cDNA were amplified through PCR using AS1 Ⅱ and ArmyC5R as primers designed according to the conserved (C1,C5) sequences of Rosaceae S-RNases. Three S-RNase genes,P.a S8 from ‘Katy’ and P.a S9,P.a S10 from ‘Xinshiji’,were amplified and cloned. Amplified DNA bands were different sizes: P.a S8 of 927 bp,P.a S9 of 992 bp,P.a S10 of 583 bp,and cDNA bands were 521 bp,521 bp,479 bp,respectively. The results of Blastn in GenBank showed that they were novel S-RNase genes and they have been deposited in GenBank (Accession No.: AY884212,AY864826,AY864825,AY853594 and AY846872). Genomic sequences showed an intron structure between C1 and C5 region. The introns of P.a S8,P.a S9,and P.a S10 were 406 bp,471 bp,104 bp and lay in the hypervariable region (RHV) between C2 and C3. Three genes were compared and displayed similarity at the nucleotide and deduced amino acid level. Most of amino acid sequences of S-RNase gene in Prunoideae (Rosaceae) were used to form their phyligenetic tree. The evolutionary relationships showed S-RNase genes did not form a distinct cluster within species. Intra-species similarity was not higher than inter-species one. Therefore,we speculated that the evolutionary of S-RNase genes in Prunoideae was not consisted with that of species.更多还原