Highly differentiated phylogeographic structure of Primula ranunculoides

Primula ranunculoides Chen is a rare and endangered species endemic to China.To reveal its phylogeographic patterns,the trnL-F and trnS-G plastid DNA of 114 individuals sampled from 11 natural populations were sequenced and analyzed.In total,10 haplotypes were identified,and populations were fixed with only one unique haplotype,except for populations YJPA and YJPB,which shared a haplotype (H9).Primula ranunculoides has a highly differentiated and significant phylogeographic structure,with an average genetic distance among populations of 0.015 and average mutation between haplotypes of 31.2 steps,significantly higher than those of related species within the genus.The high differentiation between the populations and haplotypes of this species might be explained by its limited seed dispersal ability,habitat fragmentation,isolation of geographical distance,and biennial life form.Samova,Structure,and TCS analyses unanimously supported the clustering of the 11 sampled populations into six groups,which were closely correlated with topographical features and highly differentiated among each other.Accordingly,populations from different mountains should be considered as different genetic management units for conservation purposes.