Repeated Range Expansion and Glacial Endurance of Potentilla glabra (Rosaceae) in the Qinghai‐Tibetan Plateau

Abstract

To date, little is still known about how alpine species occurring in the Qinghai-Tibetan Plateau (QTP) responded to past climatic oscillations. Here, by using variations of the chloroplast trnT-L, we examined the genetic distribution pattern of 101 individuals of Potentilla glabra, comprising both the interior QTP and the plateau edge. Phylogenetic and network analyses of 31 recovered haplotypes identified three tentative clades (A, B and C). Analysis of molecular variance (amova) revealed that most of the genetic variability was found within populations (0.693), while differentiations between populations were obviously distinct (F(st)= 0.307). Two independent range expansions within clades A and B occurring at approximately 316 and 201 thousand years ago (kya) were recovered from the hierarchical mismatch analysis, and these two expansions were also confirmed by Fu's F(S) values and 'g' tests. However, distant distributions of clade C and private haplotypes from clades A and B suggest that they had survived the Last Glacial Maximum (LGM) and previous glaciers in situ since their origins. Our findings based on available limited samples support that multiple refugia of a few cold-enduring species had been maintained in the QTP platform during LGM and/or previous glacial stages.

Phylogeographical structure inferred from cpDNA sequence variation of Zygophyllum xanthoxylon across north-west China

“…A high level of haplotype diversity within Z. xanthoxylem was also supported by the AMOVAs, which showed that a large percentage of the variation was explained by differences within populations ( Table 3). Patterns of higher haplotype diversity within populations are consistent with those found in other outbreeding species (Hamrick and Godt 1996;Nybom and Bartish 2000;Wang et al 2009b). However, due to the slow evolutionary rate of the chloroplast genome (Zurawski et al 1984), the observed haplotype diversity may reflect historical patterns.…”

“…These distinctive haplotypes was generated due to the topographic characteristics, recent population expansion or population expansion and contraction constantly by the climate volatility in East regions. This pattern happened in previous studies (Chen et al 2013;Wang et al 2009b). Table 1 for geographical details Although this study was conducted across many regions, including deserts, mountains ranges and so on, no clear effect of these acting as significant barriers was detected, as manifested in the lack phylogeographical structure.…”

Evolutionary history of Orinus thoroldii (Poaceae), endemic to the western Qinghai-Tibetan Plateau in China

“…Our permutation tests also indicated that N ST was significantly higher than G ST , suggesting the presence of a strong structure across the distribution of O. thoroldii. In addition, although the cpDNA haplotype richness was very low, only seven haplotypes were found in total, it was noteworthy that high levels of total and within population diversities were detected in O. thoroldii Wang et al, 2009b). Although seven nrITS sequence types were distributed across the entire distribution region, their phylogenetic relationships were not well resolved.…”

Initial diversification, glacial survival, and continuous range expansion of Gentiana straminea (Gentianaceae) in the Qinghai–Tibet Plateau

“…Another example shows that Potentilla glabra lodd. (Rosaceae) survived in two regions located in both the interior and edge of the QTP (Wang et al, 2009b). These studies suggest that many alpine plants in the QTP have a diverse phylogeographic history.…”