Biodiv Sci ›› 2021, Vol. 29 ›› Issue (12): 1629-1637.DOI: 10.17520/biods.2021341

• Original Papers:Plant Diversity • Previous Articles     Next Articles

Genetic structure and its causes of an important woody oil plant in Southwest China, Prinsepia utilis (Rosaceae)

Junwei Ye1,2, Bin Tian1,*()   

  1. 1 Key Laboratory of Biodiversity Conservation in Southwest China, State Forestry Administration, Southwest Forestry University, Kunming 650224
    2 Germplasm Bank of Wild Species in Southwest China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201
  • Received:2021-08-30 Accepted:2021-11-19 Online:2021-12-20 Published:2021-12-16
  • Contact: Bin Tian

Abstract:

Aims: Prinsepia utilis is an important woody oil species in temperate forests in Southwest China, however, almost nothing is known about its population genetic structure and the causes. So, we aim to study its evolutionary history through multiple nuclear microsatellite loci (nSSRs).
Methods: We sampled 377 individuals from 32 natural populations across all distribution range of P. utilis. All individuals were amplified and scored using seven self-developed nSSRs markers. Genetic structure was inferred using STRUCTURE software and principal component analysis. The most possible demographic scenario and corresponding parameters were modeled and estimated in DIYABC. Genetic diversity and genetic differentiation of each population, locus and genetic cluster were calculated. Contributions of geographic distance and environmental differences to genetic differentiation were calculate through Mantel test and partial Mantel test. At last, environmental differences among different genetic clusters was evaluated through principal component analysis using 19 climatic variables.
Results: All population can be divided into four genetic groups that are Himalayas, Hengduan Mountains, west and east Yunnan-Guizhou Plateau genetic groups from west to east. The greatest genetic differentiation occurs between populations in the Himalayas and other regions. In comparison with the Himalayan and east Yunnan-Guizhou Plateau groups, the Hengduan Mountains and west Yunnan-Guizhou Plateau groups have higher proportion of genetic mixture from other groups. Population demographic history analysis indicate two central groups are formed after Himalayas and east Yunnan-Guizhou Plateau groups, all divergences are occurred in late Pleistocene. The analyses of isolation by distance and isolation by environment show that the genetic differentiation of P. utilis is mainly caused by environmental difference. Environmental difference analysis using 19 climatic variables shows various difference among groups with significant difference exist between Himalayas and east Yunnan-Guizhou Plateau groups.
Conclusion: The distinct genetic structure of P. utilis is formed through the combination of Pleistocene climatic changes, complicated environment and its own biological characters. Combined with ecological niche modeling analysis in different periods, we suggest protection of genetic resources in Himalayas and Yunnan-Guizhou Plateau should be first priority.

Key words: nuclear microsatellites, genetic diversity, principal component analysis, Himalayas