Abstract

Organellar genomes are small, circular entities that provide unique advantages as compared to the nuclear genome. The present study was aimed at evaluating the efficiency of utilizing mitochondrial single nucleotide polymorphisms (SNPs) approach in separating barley cultivars. Sequences generated via next-generation sequencing were further utilized to confirm the incidence of heteroplasmy in barley mitochondrial genome. The analysis involved seven cultivated barley (Hordeum vulgare subsp. vulgare) (VG) and one wild (H. vulgare subsp. spontaneum) (SP) genotypes. A total of 73 million paired-end reads per mitochondrial genomes across the eight barley genotypes were generated using Illumina HiSeq 2000 platform. Sequences of each genotype were separately aligned to the published barley mitochondrial reference genome, thus SNPs were detected. The overall results indicated the efficiency of using mitochondrial SNPs as a molecular marker in distinguishing among barley genotypes. Unique SNPs were determined in six out of the eight genotypes, where Giza131 and Giza129 had no specific mitochondrial SNPs, while Giza130 showed the largest number of unique mitochondrial SNPs. The phylogenetic tree indicated the close relationship between Giza129 and Giza130. Interestingly, SP was not clearly discriminated among genotypes.

摘要

细胞核基因组是小的圆形实体，与核基因组相比具有独特的优势。本研究旨在评估利用线粒体单核苷酸多态性（SNPs）方法分离大麦品种的效率。通过下一代测序产生的序列被进一步用于确认大麦线粒体基因组中异质性的发生率。分析中共有7个栽培大麦（大麦亚种大麦）（VG）和一个野生（H.大麦亚种。根子）（SP）基因型。使用Illumina HiSeq 2000平台，在八种大麦基因型中，每个线粒体基因组的配对末端读数总计7300万。将每种基因型的序列分别与已发表的大麦线粒体参考基因组进行比对，从而检测出SNP。总体结果表明，使用线粒体SNPs作为分子标记来区分大麦基因型是有效的。在八种基因型中的六种中确定了独特的SNP，其中Giza131和Giza129没有特定的线粒体SNP，而Giza130显示出最多的独特线粒体SNP。系统发育树表明Giza129和Giza130之间的密切关系。有趣的是，没有明确区分基因型之间的SP。