梨主栽品种叶绿体高变区accD-psaI的遗传多样性研究

Genetic Diversity of Pear Cultivars Revealed by cpDNA Hypervariable Region accD-psaI

梨叶绿体DNA结构高度保守,利用其非编码区的高变区域accD-psaI,从母系遗传的角度评价梨主要栽培品种的遗传多样性和亲缘关系,为梨育种计划亲本的选择提供参考。结果显示,42个梨品种的叶绿体高变区域accD-psaI的扩增片段长度为653~932bp,其中简约信息性突变位点3个,占片段总长的0.32%,插入/缺失片段（INDEL）为6个,总长280bp,占片段总长的30.04%。42份材料共检测到6个单倍型,单倍型多样性Hd为0.78,不同梨系统Hd的变化范围在0.29~0.80之间,秋子梨和西洋梨栽培品种的Hd最低,为0.29,种间杂交新品种的的Hd最高,为0.80。白梨、秋子梨、沙梨、新疆梨、西洋梨和种间杂交品种的单倍型个数分别为3、2、2、3、2和3。中介网络图显示,单倍型H1和H3,H5和H6的亲缘关系近。研究结果为育种计划亲本的选配提供参考依据。

Genetic diversity and phylogenetic relationship of several pear cultivars were evaluated by hypervariable region accD-psaI of chloroplast in non-coding regions.Results showed that the amplified fragment length of the hypervariable region accD-psaI in chloroplast of 42 pear cultivars ranged from 653 to 932bps including 3mutation sites at 0.32 percent of the whole fragment length,and 6INDELs with the length of 280 bp,which was 30.04% percents of the whole length.Six haplotypes were detected from the 42 cultivars of pear.The haplotype diversity（Hd）was 0.78.Haplotype diversity（Hd）of different pear species ranged from 0.29 to 0.80.Hd（0.29）of Pyrus ussuriensis Maxim was the lowest and that of the hybrids of intra-species was the highest at 0.80.The haplotypes in Chinese white pear,Chinese sand pear,Pyrus ussuriensis Maxim,Sinkiang pear,European pear and intra-specie hybrids were 3,2,2,3,2and 3,respectively.The haplotypes network showed that H1 and H3,H5 and H6had closer relationship.