三个Hordeum Linn.叶绿体基因组

Hordeum Linn. is distributed almost everywhere from the southern hemisphere to the northern hemisphere. Among them, three wild species (H. bogdanii, H. brevisubulatum and H. violaceum) could serve as important material for genetic improvement. Up to now, only two chloroplast (cp) genomes of Hordeum species (H. vulgare and H. spontaneum) have been reported. Therefore, it is necessary for us to make a comparison for inter-species, and cp genomes of three Hordeum species were sequenced and assembled, in order to explore the degree of variation each other. The research results illuminated that compared to the other two species (H. brevisubulatum and H. violaceum) with approximately the same cp genome, H. bogdanii had significant differences. This result can be explained by cp genome size, repeat sequences, insertions/deletions (In/Dels), Single Nucleotide Polymorphisms (SNPs) and invert repeats (IR) expansion or contraction. Meanwhile, a large number of SNPs, In/Dels and repeated sequences events were found in three Hordeum species. In addition, a series of hotspots regions (tRNA-UGU～ndhJ, psbE～rps18, ndhF～tRNA-UAG, and so on) were identified by the mVISTA and Mauve, and five highly polymorphic genes (tRNA-UGC, tRNA-UAA, tRNA-UUU, tRNA-UAC, ndhA) were proved by the nucleotide polymorphisms (pi). What is attention that the phylogenic tree among these species were also analyzed. This article provides a theoretical basis for understanding the evolution of Hordeum Linn and expands the cp genome database.