关键词: 杜梨, 叶绿体基因组, CP-SSR

Abstract: In this study，the chloroplast（cp）genome sequencing of Pyrus betulaeolia was done by high-throughput sequencing，and the genome sequence structure was analyzed. The results showed that like most of higher plants，cp genome had the typical circular double-chain tetrad structure. The P. betulaefolia cp genome was 160 058 bp in size，containing 61 SSR loci（58 single nucleotide repeats and 3 dinucleotide repeats）and 56 RNA editing sites，all of which caused amino acid changes. The comparison with P. pyrifolia，P. pashia，and P. spinosa showed that the genome types and numbers were relatively conservative，indicating that the Pyrus evolved slowly. A total of 351 single nucleotide polymorphisms and 217 InDels were detected in four Pyrus species.

Key words: Pyrus betulaefolia, chloroplast genome, CP-SSR