2011/09/05 by Qing-Ying Zhang, Qingying Zhang, Yu-Juan Zhao +1
Biochemistry, Genetics and Molecular Biology · #Biological dispersal #Biology #Chloroplast DNA #Demography #Evolutionary biology #Gene #Genetic diversity and population structure #Genetic structure #Genetic variation #Genetics #Genomics and Phylogenetic Studies #Isolation by distance #Phylogenetic tree #Phylogeography #Plant and Fungal Species Descriptions #Population #Population genetics
paper · doi:10.1071/bt11024
openalex publication_date 2011/09/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Psammosilene tunicoides is a narrowly distributed and endemic species in south-western China. An investigation of sequence variation at two chloroplast DNA (cpDNA) regions (rpL16, trnQ-5'rps16) and one nuclear DNA (nDNA) locus (GPA1) were carried out to survey the population structure and population history of the species. Among the 22 populations across its geographical range, nine chloroplast haplotypes and 17 nuclear alleles were identified. Both cpDNA and nDNA consistently revealed high levels of population differentiation (GST = 0.604 and 0.540, respectively), suggesting a distinct phylogeographic structure (NST > GST, P < 0.01). This high genetic differentiation might be a combined effect of breeding system, limited pollen and seed dispersal and geographic isolation of populations. The level of haplotype diversities (cpDNA, hT = 0.575; nDNA, hT = 0.724) were high, but the nucleotide diversities (cpDNA, p = 0.00099; nDNA, p = 0.00105) were low. These results together with the star-like phylogenetic pattern and neutrality tests indicate that P. tunicoides has experienced a population expansion event in its evolution. Limited genetic exchange after population expansion was supported by the pronounced genetic differentiation among populations as well as evidence for ‘isolation-by-distance’ revealed by cpDNA. Due to high population subdivision and complex landscape, as many populations as possible should be considered for genetic conservation.