AUTHOR=Li Jiaokun , Xu Hui , Song Yunpeng , Tang Lulu , Gong Yanbing , Yu Runlan , Shen Li , Wu Xueling , Liu Yuandong , Zeng Weimin 

TITLE=Geography Plays a More Important Role than Soil Composition on Structuring Genetic Variation of Pseudometallophyte Commelina communis

JOURNAL=Frontiers in Plant Science

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2016.01085

DOI=10.3389/fpls.2016.01085

ISSN=1664-462X

ABSTRACT=<p>Pseudometallophytes are excellent models to study microevolution and local adaptation to soil pollution, as they can grow both on metalliferous and contrasting non-metalliferous soils. Although, there has been accumulating evidence for the effects of edaphic conditions and geographical isolation on the genetic structure of pesudometallophytes, it is still a difficult problem in evolutionary biology to assess their relative importance. In this study, we investigated the spatial patterns of genetic variability, population differentiation and genetic groups in pseudometallophyte <italic>Commelina communis</italic> with 12 microsatellite loci. Eight metallicolous and six non-metallicolous populations of <italic>C</italic>. <italic>communis</italic> were sampled from cupriferous sites and surrounding non-contaminated areas in China. Neither significant reduction in genetic diversity nor apparent founder and bottleneck effects were observed in metallicolous populations of <italic>C. communis.</italic> Based on Bayesian and Neighbor-Joining clustering analyses and a principal coordinates analysis, all sampled populations were found to be mainly separated into three genetic groups, corresponding well to their geographical locations rather than edaphic origins. Moreover, a significant and strong correlation between population genetic divergence and geographical distance were detected by Mantel test (<italic>r</italic> = 0.33; <italic>P</italic> &lt; 0.05) and multiple matrix regression with randomization (MMRR; β<sub>D</sub> = 0.57, <italic>P</italic> &lt; 0.01). However, the effect of copper concentration on genetic patterns of <italic>C</italic>. <italic>communis</italic> was not significant (MMRR; β<sub>E</sub> = -0.17, <italic>P</italic> = 0.12). Our study clearly demonstrated that the extreme edaphic conditions in metalliferous areas had limited effects on the genetic variability in <italic>C</italic>. <italic>communis</italic>. Geographic distance played a more important role in affecting the genetic structure of <italic>C</italic>. <italic>communis</italic> than soil composition did. In <italic>C</italic>. <italic>communis</italic>, the geographically disjunctive populations on metalliferous soils had multiple origins and evolved independently from nearby non-metallicolous populations.</p>