Genetic diversity and its conservation implications of Vitex rotundifolia (Lamiaceae) populations in East Asia

Yiqi Sun; Hong Yang; Qiaoyan Zhang; Luping Qin; Pan Li; Joongku Lee; Shichao Chen; Khalid Rahman; Tingguo Kang; Min Jia

doi:10.7717/peerj.6194

Genetic diversity and its conservation implications of Vitex rotundifolia (Lamiaceae) populations in East Asia

PeerJ. 2019 Jan 11:7:e6194. doi: 10.7717/peerj.6194. eCollection 2019.

Authors

Yiqi Sun^#¹, Hong Yang^#², Qiaoyan Zhang³, Luping Qin^{4

3}, Pan Li⁵, Joongku Lee⁶, Shichao Chen⁷, Khalid Rahman⁸, Tingguo Kang¹, Min Jia⁴

Affiliations

¹ College of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian, Dalian, Liaoning, China.
² School of Medicine, Tongji University, Shanghai, China.
³ College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China.
⁴ Department of Pharmacognosy, Second Military Medical University School of Pharmacy, Shanghai, China.
⁵ Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, and Laboratory of Systematic & Evolutionary Botany and Biodiversity, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
⁶ Department of Environment and Forest Resources, College of Agriculture & Life Sciences, Chungnam National University, Daejeon, South Korea.
⁷ College of Life Science and Technology, Tongji University, Shanghai, China.
⁸ School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom.

^# Contributed equally.

Abstract

Vitex rotundifolia is an important coastal and medicinal plant, and is recorded in the List of the Important Wild Plants for Conservation in China and Japan. However, an effective conservation strategy is lacking. In the present study, the genetic diversity and population structure were analyzed using phylogeographical methods based on the trnH-psbA and trnG-trnS intergenic spacers of the chloroplast DNA (cpDNA) sequences from 157 individuals from 25 sampling sites for V. rotundifolia and V. trifolia plus the internal transcribed spacer (ITS) of the nuclear ribosomal DNA (nrDNA) sequences of 177 individuals from 27 sampling sites. The results showed that V. rotundifolia and V. trifolia had eight cpDNA and two nrDNA haplotypes, respectively, and the V. rotundifolia has a low level of genetic diversity (haplotype diversity h _d,cp = 0.360, h _d,nr = 0.440), a more pronounced genetic differentiation among populations (population differentiation at the species level (G _ST) = 0.201, population differentiation at the allele level (N _ST) = 0.462), and an insignificantly different phylogeographical structure (N _ST > G _ST, P > 0.05). In addition, haplotype network analyses indicated that V. rotundifolia and V. trifolia have distinct haplotypes. Divergence dating based on BEAST software analyses showed that most cpDNA clades diverged in the late Pleistocene era. Demographic analysis indicated that V. rotundifolia underwent a rapid demographic expansion. Some scientific strategies are suggested for resource conservation of V. rotundifolia based on its genetic diversity and population structure.

Keywords: Phylogeography; Vitex rotundifolia; Vitex trifolia; cpDNA; nrDNA.

Grants and funding

This study was financially supported by the National Natural Science Foundation of China (No. 81573599, No. 81371776), the Science and Technology Basic Work, Project of the Ministry of Science and Technology, China (No. 2015FY111500). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.