AUTHOR=Chen Changjie , Miao Yuhuan , Luo Dandan , Li Jinxin , Wang Zixin , Luo Ming , Zhao Tingting , Liu Dahui 

TITLE=Sequence Characteristics and Phylogenetic Analysis of the Artemisia argyi Chloroplast Genome

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.906725

DOI=10.3389/fpls.2022.906725

ISSN=1664-462X

ABSTRACT=<p><italic>Artemisia argyi</italic> Levl. et Van is an important <italic>Asteraceae</italic> species with a high medicinal value. There are abundant <italic>A. argyi</italic> germplasm resources in Asia, especially in China, but the evolutionary relationships of these varieties and the systematic localization of <italic>A. argyi</italic> in the family <italic>Asteraceae</italic> are still unclear. In this study, the chloroplast (cp) genomes of 72 <italic>A. argyi</italic> varieties were systematically analyzed. The 72 varieties originated from 47 regions in China at different longitudes, latitudes and altitudes, and included both wild and cultivated varieties. The <italic>A. argyi</italic> cp genome was found to be ∼151 kb in size and to contain 114 genes, including 82 protein-coding, 28 tRNA, and 4 rRNA genes. The number of short sequence repeats (SSRs) in <italic>A. argyi</italic> cp genomes ranged from 35 to 42, and most of them were mononucleotide A/T repeats. A total of 196 polymorphic sites were detected in the cp genomes of the 72 varieties. Phylogenetic analysis demonstrated that the genetic relationship between <italic>A. argyi</italic> varieties had a weak relationship with their geographical distribution. Furthermore, inverted repeat (IR) boundaries of 10 <italic>Artemisia</italic> species were found to be significantly different. A sequence divergence analysis of <italic>Asteraceae</italic> cp genomes showed that the variable regions were mostly located in single-copy (SC) regions and that the coding regions were more conserved than the non-coding regions. A phylogenetic tree was constructed using 43 protein-coding genes common to 67 <italic>Asteraceae</italic> species. The resulting tree was consistent with the traditional classification system; <italic>Artemisia</italic> species were clustered into one group, and <italic>A. argyi</italic> was shown to be closely related to <italic>Artemisia lactiflora</italic> and <italic>Artemisia montana</italic>. In summary, this study systematically analyzed the cp genome characteristics of <italic>A. argyi</italic> and compared cp genomes of <italic>Asteraceae</italic> species. The results provide valuable information for the definitive identification of <italic>A. argyi</italic> varieties and for the understanding of the evolutionary relationships between <italic>Asteraceae</italic> species.</p>