The impacts of polyploidy, geographic and ecological isolations on the diversification of Panax (Araliaceae)

BMC Plant Biology

Research Article

Ming-Rui Li¹  Cui Zhang¹  Hong-Xing Xiao¹  Peng Jiang²  Feng-Xue Shi²  Ya-Ling Li²  Bao Liu²  Lin-Feng Li²  Yue-Zhi Pan³ 

[1] Institute of Grassland Science, Northeast Normal University, Key Laboratory of Vegetation Ecology, Ministry of Education, 130024, Changchun, China;Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, 130024, Changchun, China;Kunming Institute of Botany, Chinese Academy of Sciences, 650201, Kunming, China;

关键词: Chloroplast;    Disjunt distribution;    nrITS;    Nucleotide diversity;    Panax;    Single copy nuclear gene;    Whole genome duplication;   

DOI  :  10.1186/s12870-015-0669-0

 received in 2015-09-09, accepted in 2015-11-23,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundPanax L. is a medicinally important genus within family Araliaceae, where almost all species are of cultural significance for traditional Chinese medicine. Previous studies suggested two independent origins of the East Asia and North America disjunct distribution of this genus and multiple rounds of whole genome duplications (WGDs) might have occurred during the evolutionary process.ResultsWe employed multiple chloroplast and nuclear markers to investigate the evolution and diversification of Panax. Our phylogenetic analyses confirmed previous observations of the independent origins of disjunct distribution and both ancient and recent WGDs have occurred within Panax. The estimations of divergence time implied that the ancient WGD might have occurred before the establishment of Panax. Thereafter, at least two independent recent WGD events have occurred within Panax, one of which has led to the formation of three geographically isolated tetraploid species P. ginseng, P. japonicus and P. quinquefolius. Population genetic analyses showed that the diploid species P. notoginseng harbored significantly lower nucleotide diversity than those of the two tetraploid species P. ginseng and P. quinquefolius and the three species showed distinct nucleotide variation patterns at exon regions.ConclusionOur findings based on the phylogenetic and population genetic analyses, coupled with the species distribution patterns of Panax, suggested that the two rounds of WGD along with the geographic and ecological isolations might have together contributed to the evolution and diversification of this genus.

【 授权许可】

CC BY   
© Shi et al. 2015