Genetic diversity and population structure analysis in a large collection of white clover (Trifolium repens L.) germplasm worldwide

Feifei Wu; Sainan Ma; Jie Zhou; Chongyang Han; Ruchang Hu; Xinying Yang; Gang Nie; Xinquan Zhang

doi:10.7717/peerj.11325

Genetic diversity and population structure analysis in a large collection of white clover (Trifolium repens L.) germplasm worldwide

PeerJ. 2021 May 3:9:e11325. doi: 10.7717/peerj.11325. eCollection 2021.

Authors

Feifei Wu^#¹, Sainan Ma^#¹, Jie Zhou¹, Chongyang Han¹, Ruchang Hu¹, Xinying Yang¹, Gang Nie¹, Xinquan Zhang¹

Affiliation

¹ Department of Grassland Science, Animal Science and Technology College, Sichuan Agricultural University, Chengdu, Sichuan, China.

^# Contributed equally.

Abstract

White clover is an important temperate legume forage with high nutrition. In the present study, 448 worldwide accessions were evaluated for the genetic variation and polymorphisms using 22 simple sequence repeat (SSR) markers. All the markers were highly informative, a total of 341 scored bands were amplified, out of which 337 (98.83%) were polymorphic. The PIC values ranged from 0.89 to 0.97 with an average of 0.95. For the AMOVA analysis, 98% of the variance was due to differences within the population and the remaining 2% was due to differences among populations. The white clover accessions were divided into different groups or subgroups based on PCoA, UPGMA, and STRUCTURE analyses. The existence of genetic differentiation between the originally natural and introduced areas according to the PCoA analysis of the global white clover accessions. There was a weak correlation between genetic relationships and geographic distribution according to UPGMA and STRUCTURE analyses. The results of the present study will provide the foundation for future breeding programs, genetic improvement, core germplasm collection establishment for white clover.

Keywords: Genetic variation; Population structure; SSR; White clover.

Grants and funding

This study was supported by the earmarked fund for Modern Agro-industry Technology Research System (No.CARS-34) and National Project on Sci-Tec Foundation Resources Survey (2017FY100602). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.