AUTHOR=Chao Zhi , Hong Xiaoxi , Xie Xuena , Huang Rong , Tian Enwei 

TITLE=Phylogenomic analysis of Bupleurum in Western Sichuan, China, including an overlooked new species

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1294670

DOI=10.3389/fpls.2023.1294670

ISSN=1664-462X

ABSTRACT=<p>A comparative analysis of chloroplast (cp) genomes and 45s nuclear ribosomal DNA (nrDNA), and a phylogenomic study of six closely related species (including an overlooked new species) of genus <italic>Bupleurum</italic> from the western part of Sichuan Province in southwestern China were performed. The six species are similar morphologically and it is difficult to identify them; moreover, their genetic relationships remain unclear. It was found that the cp genomes of the six <italic>Bupleurum</italic> species were extremely similar, and they were highly homogeneous in terms of cp genome structure, genes and its arrangement. Intergenic spacer <italic>rpl</italic>32-<italic>trn</italic>L, <italic>pet</italic>A-<italic>psb</italic>J, <italic>trn</italic>K-<italic>rps</italic>16, and the coding gene <italic>ycf</italic>1 were considered highly variable. In phylogenetic trees constructed based on the complete cp genome, protein-coding sequences, nrDNA and ITS sequences, Chinese <italic>Bupleurum</italic> species all formed two major clades; among these trees, nrDNA tree had the best species resolution; the highly variable regions showed no advantage over other molecular markers. Among the six <italic>Bupleurum</italic> species, <italic>B. malconense, B. sichuanense</italic> were close relatives to <italic>B. chinense</italic> and <italic>B. yinchowense</italic>, <italic>B. chaishoui</italic> may also be a consanguinity, while <italic>B. microcephalum, B. wenchuanense</italic>, and the new species <italic>B. pseudochaishoui</italic> were closely related. At the end, the new species <italic>B. pseudochaishoui</italic> Z. Chao sp. nov. was described and illustrated, and a key to the six species was tabulated.</p>