Influence of environmental factors on the genetic variation of the aquatic macrophyte Ranunculus subrigidus on the Qinghai-Tibetan Plateau

Abstract

BackgroundDue to the environmental heterogeneity along elevation gradients, alpine ecosystems are ideal study objects for investigating how ecological variables shape the genetic patterns of natural species. The highest region in the world, the Qinghai-Tibetan Plateau, is a hotspot for the studies of evolutionary processes in plants. Many large rivers spring from the plateau, providing abundant habitats for aquatic and amphibious organisms. In the present study, we examined the genetic diversity of 13 Ranunculus subrigidus populations distributed throughout the plateau in order to elucidate the relative contribution of geographic distance and environmental dissimilarity to the spatial genetic pattern.ResultsA relatively low level of genetic diversity within populations was found. No spatial genetic structure was suggested by the analyses of molecular variance, Bayesian clustering analysis and Mantel tests. Partial Mantel tests and multiple matrix regression analysis showed a significant influence of the environment on the genetic divergence of the species. Both climatic and water quality variables contribute to the habitat heterogeneity of R. subrigidus populations.ConclusionsOur results suggest that historical processes involving long-distance dispersal and local adaptation may account for the genetic patterns of R. subrigidus and current environmental factors play an important role in the genetic differentiation and local adaptation of aquatic plants in alpine landscapes.

Spatial genetic structuring in a widespread wetland plant on a plateau: Effects of elevation‐driven geographic isolation and environmental heterogeneity

“…Nevertheless, long‐distance dispersal across mountains has been detected in S. filiformis , according to the distribution patterns of SSR Cluster 3/cpDNA Clade Ⅲ. MD1 (Zhaling‐Eling Lakes) is one of the largest QTP lakes that can accommodate migrating waterfowls for breeding (Zhang, 2015), which may explain its genetic similarity with distant populations. A similar situation was also found in another submerged plant, Ranunculus subrigidus (Wu, Xu, Zhang, Wiegleb, & Hou, 2019). Additionally, populations located in the mountains (YSP and TGL) that accommodated individuals from different genetic clusters also supported the occasional dispersal across the mountains.…”

Genetic structure of Zannichellia L. populations according to mountain barriers in Iran as revealed by ISSR and SRAP markers

“…Mountains and river valleys act as a genetic barrier and a corridor for gene flow, respectively. Small and isolated populations are affected by founder effects or genetic drifts, which increase genetic differentiation (Wei et al, 2013;Wu et al, 2019;Xia et al, 2020). Strong genetic differentiation was observed among the Lithuanian river populations of Nuphar lutea (Vyšniauskienė et al, 2020), the invasive Eurasian Myriophyllum populations (Thum et al, 2020), the Batrachium bungei populations growing in the rivers of the Hengduan Mountains in China (Wang et al, 2010), and those of Iranian Stuckenia .…”

Extensive Sympatry and Frequent Hybridization of Ecologically Divergent Aquatic Plants on the Qinghai-Tibetan Plateau

“…Total genomic DNA was extracted using the DNAsecure Plant Kit (Tiangen Biotech, Beijing, China). Microsatellite markers (7 loci for Stuckenia, Nies and Reusch, 2004 ; Wu et al, 2020 ; 17 loci for Ranunculus, Wu et al, 2017 ; Wu et al, 2019 ) and one cpDNA fragment ( rpl32-trnL ) were chosen to identify kinships. The primers “rpL32-F” and “trnL (UAG) ” ( Shaw et al, 2007 ) were used to amplify and sequence the region.…”