Characterization of the complete chloroplast genome of traditional Tibetan herb, Rheum Pumilum Maxim. (Polygonaceae).

The complete chloroplast genome sequence of traditional Tibetan herb, Rheum pumilum Maxim. was analyzed. The complete chloroplast genome of R. pumilum is 162,213 bp in size and has a 27.27% GC content. In the typical circular quadripartite structure, there was a pair of inverted repeat (IR) regions with 31,023 bp in length, which separated by a large single-copy (LSC) region (87,424 bp) and a small single-copy (SSC) region (12,743 bp). The chloroplast genome of R. pumilum contained 131 unigenes, which was composed of 86 protein-coding genes, 37 tRNA and 8 rRNA genes. Moreover, 238 SSRs were identified and 58.8% of them existed in LSC region. A maximum likelihood (ML) phylogenetic analysis based on chloroplast genomes indicated that R. pumilum was closely related to R. pulmatum, R. tangutica, and R. officinale. Our results would provide a valuable resource for resource utilization and the phylogenetic studies of Rheum in Polygonaceae.