Population structure and genetic diversity in the nannandrous moss Homalothecium lutescens: does the dwarf male system facilitate gene flow?

BMC Evolutionary Biology

Research Article

Frida Rosengren¹  Nils Cronberg¹  Bengt Hansson² 

[1]Department of Biology, Biodiversity, Lund University, Ecology Building, SE-223 62, Lund, Sweden

[2]Department of Biology, Lund University, Molecular Ecology and Evolution Lab, Ecology Building, SE-223 62, Lund, Sweden

关键词: Bryophytes;    Genetic variation;    Population structure;    SNP;    Long-distance dispersal;   

DOI  :  10.1186/s12862-015-0545-4

 received in 2015-06-18, accepted in 2015-11-17,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundNannandry is a sexual system where males (”dwarf males”) are much smaller than the conspecific females. Dwarf males occur in a wide range of unrelated organisms but the evolutionary advantages of this condition are poorly understood. The dwarf male sexual system results in differences in the mode of dispersal and establishment as well as the life span between males and females. Such differences must have profound effects on the population dynamics and genetic structures. We have studied four populations of the nannandrous moss Homalothecium lutescens in southern Sweden. We genotyped dwarf males and female shoots with the aim of describing the genetic diversity and structure of the populations.ResultsDwarf males were most related to their host shoot, then their colony (within 0.5 m2) and then the rest of the population, which suggests restricted spore dispersal. However, a few dwarf males in each population appeared to originate from other colonies and sometimes even other populations. Genetic diversity of dwarf males was generally high but showed no tendency to be consistently higher or lower than female genetic diversity within the four populations.ConclusionsAlthough most dwarf males have local origin, sporadic dispersal events occur. The ability of the dwarf males to establish in high numbers in mature colonies facilitates gene flow between populations as well as increases the potential to accumulate genetic diversity within populations.

【 授权许可】

CC BY   
© Rosengren et al. 2015