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

Zhi Chao; Xiaoxi Hong; Xuena Xie; Rong Huang; Enwei Tian

doi:10.3389/fpls.2023.1294670

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

Front Plant Sci. 2023 Nov 27:14:1294670. doi: 10.3389/fpls.2023.1294670. eCollection 2023.

Authors

Zhi Chao^{1

2

3}, Xiaoxi Hong², Xuena Xie², Rong Huang², Enwei Tian²

Affiliations

¹ Department of Pharmacy, Zhujiang Hospital, Southern Medical University, Guangzhou, China.
² Faculty of Medicinal Plant and Pharmacognosy, School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China.
³ Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics, Guangzhou, China.

Abstract

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 Bupleurum 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 Bupleurum species were extremely similar, and they were highly homogeneous in terms of cp genome structure, genes and its arrangement. Intergenic spacer rpl32-trnL, petA-psbJ, trnK-rps16, and the coding gene ycf1 were considered highly variable. In phylogenetic trees constructed based on the complete cp genome, protein-coding sequences, nrDNA and ITS sequences, Chinese Bupleurum 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 Bupleurum species, B. malconense, B. sichuanense were close relatives to B. chinense and B. yinchowense, B. chaishoui may also be a consanguinity, while B. microcephalum, B. wenchuanense, and the new species B. pseudochaishoui were closely related. At the end, the new species B. pseudochaishoui Z. Chao sp. nov. was described and illustrated, and a key to the six species was tabulated.

Keywords: Bupleurum; Bupleurum pseudochaishoui Z. Chao sp. nov.; Western Sichuan; chloroplast genome; nuclear ribosomal DNA; phylogenomic analysis.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study is supported by grants to ZC from the National Natural Science Foundation of China (NSFC 30873387, 81373905), and Guangdong Provincial Natural Science Foundation (2014A030313321).