Intraspecific lineage divergence and its association with reproductive trait change during species range expansion in central Eurasian wild wheat Aegilops tauschii Coss. (Poaceae)

BMC Evolutionary Biology

Research Article

Yoshihiro Matsuoka¹  Taihachi Kawahara²  Shigeo Takumi³ 

[1] Fukui Prefectural University, Matsuoka, Eiheiji, Yoshida, Fukui, Japan;Laboratory of Crop Evolution, Plant Germ-plasm Institute, Graduate School of Agriculture, Kyoto University, Mozume, Muko, Kyoto, Japan;Laboratory of Plant Genetics, Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, Japan;

关键词: Adaptation;    Dispersal;    Flowering time;    Life history;    Natural variation;    Phenology;    Spike and spikelet traits;    Species range expansion;   

DOI  :  10.1186/s12862-015-0496-9

 received in 2015-04-19, accepted in 2015-09-22,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundHow species ranges form in landscapes is a matter of long-standing evolutionary interest. However, little is known about how natural phenotypic variations of ecologically important traits contribute to species range expansion. In this study, we examined the phylogeographic patterns of phenotypic changes in life history (seed production) and phenological (flowering time) traits during the range expansion of Aegilops tauschii Coss. from the Transcaucasus and Middle East to central Asia.ResultsOur comparative analyses of the patterns of natural variations for those traits and their association with the intraspecific lineage structure showed that (1) the eastward expansion to Asia was driven by an intraspecific sublineage (named TauL1b), (2) high seed production ability likely had an important role at the initial dispersal stage of TauL1b’s expansion to Asia, and (3) the phenological change to early flowering phenotypes was one of the key adaptation events for TauL1b to further expand its range in Asia.ConclusionsThis study provides for the first time a broad picture of the process of Ae. tauschii’s eastward range expansion in which life history and phenological traits may have had respective roles in its dispersal and adaptation in Asia. The clear association of seed production and flowering time patterns with the intraspecific lineage divergence found in this study invites further genetic research to bring the mechanistic understanding of the changes in these key functional traits during range expansion within reach.

【 授权许可】

CC BY   
© Matsuoka et al. 2015