Chloroplast genome characterization of Bupleurum dracaenoides, a critically endangered woody species endemic to China, with insights of Apioideae phylogeny

Bupleurum dracaenoides, published in 2013, is a woody species of Bupleurum, and is critically endangered and endemic to southwest China. In this study, we reported for the first time the assembled and annotated complete chloroplast genome of B. dracaenoides based on high-throughput sequencing. The total chloroplast genome size is 155,140 bp in length, including two inverted repeats (IRs) of 26,140 bp, separated by a large single copy (LSC, 85,323 bp) and a small single copy (SSC, 17,537 bp). The genome consists of 113 unique genes, including 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. Comparative analysis of chloroplast genome among four Bupleurum species showed that B. dracaenoides presented more variations relative to other three previously reported related species. Phylogenetic analysis of 42 Apiaceae species based on 66 protein-coding genes sequences showed that Bupleurum species formed an early diverged monophyletic clade of Apiaceae subfamily Apioideae, the phylogenetic relationships among tribal level clades of Apioideae were consistent with those reported in previous studies.