Running Head: Population genetic structure of P. villosa
Ting
Lv1,2, AJ Harris3, Tao
Liu1,2, Ruifang Liang4,5, Zilan
Ma4,5, Yuping Liu*4,5, Xu
Su*1, 2, 4,5
1 School of Geosciences, Qinghai Normal University, Xining 810008, P. R.
China
2 Key Laboratory of Education Ministry of Earth Surface Processes and
Ecological Conservation of the Qinghai-Tibet Plateau, Qinghai Normal
University, Xining 810008, P. R. China
3 Key Laboratory of Plant Resources Conservation and Sustainable
Utilization, South China Botanical Garden, Chinese Academy of Sciences,
Guangzhou 510650, P. R. China
4 Key Laboratory of Medicinal Plant and Animal Resources of the
Qinghai‐Tibet Plateau in Qinghai Province, School of Life Science,
Qinghai Normal University, Xining 810008, P. R. China
5 Academy of Plateau Science and Sustainability, Xining 810016, P. R.
China
* Correspondence to:
Xu Su - Phone: +86 971 6134763; fax: +86 971 6134763; E-mail address:
xusu8527972@126.com
OR
Yuping Liu - Phone: +86 971 6134763; fax: 86 971 6134763; E-mail
address: lyp8527970@126. com
AJ Harris contributed equally to this work.
Abstract
We sought to generate a preliminary demographic framework forPsammochloa villosa to support of future studies of this
ecologically important desert grass species, its conservation, and
sustainable utilization. Psammochloa villosa occurs in the Inner
Mongolian Plateau where it is frequently the dominant species and is
involved in sand stabilization and wind breaking. Here, we characterized
the genetic diversity and structure of 210 individuals from 43 natural
populations of P. villosa using amplified fragment length
polymorphism (AFLP) markers. We obtained 1728 well-defined amplified
bands from eight pairs of primers, of which 1654 bands (95.72%) were
polymorphic. Results obtained from the AFLPs estimated a number of
effective alleles among populations of 1.3229, a Nei’s standard genetic
distance value of 0.2056, a Shannon index of 0.3316, a coefficient of
gene differentiation (G ST) of 0.4689, and a gene
flow parameter (N m) of 0.5761.
All
these values indicate that there is abundant genetic diversity, but
limited gene flow in P. villosa . However, an analysis of
molecular variance (AMOVA) showed that genetic variation mainly exists
within 43 populations of the species (64.16%), and we found that the
most genetically similar populations were often not geographically
adjacent. Thus, this suggests that the mechanisms of gene flow are
surprisingly complex in the species and may occur over long distances.
In
addition, we predicted the distribution dynamics of P. villosabased on the spatial distribution modeling and found that its range has
contracted continuously since the last inter-glacial period. We
speculate that dry, cold climates have been critical in determining the
geographic distribution of P. villosa during the Quaternary
period. Our study provides new insights into the population genetics and
evolutionary history of P. villosa in the Inner Mongolian
Plateau,
which can be used to design in-situ conservation actions and to
prioritize sustainable utilization of germplasm resources.
Keywords: desert grasslands; population genetics;
SAMOVA; ecological niche modelling; Inner Mongolian Plateau;