Phylogeography of Camellia taliensis (Theaceae) inferred from chloroplast and nuclear DNA: insights into evolutionary history and conservation.

ABSTRACT: BACKGROUND:As one of the most important but seriously endangered wild relatives of the cultivated tea, Camellia taliensis harbors valuable gene resources for tea tree improvement in the future. The knowledge of genetic variation and population structure may provide insights into evolutionary history and germplasm conservation of the species. RESULTS:Here, we sampled 21 natural populations from the species' range in China and performed the phylogeography of C. taliensis by using the nuclear PAL gene fragment and chloroplast rpl32-trnL intergenic spacer. Levels of haplotype diversity and nucleotide diversity detected at rpl32-trnL (h?=?0.841; ??=?0.00314) were almost as high as at PAL (h?=?0.836; ??=?0.00417). Significant chloroplast DNA population subdivision was detected (GST?=?0.988; NST?=?0.989), suggesting fairly high genetic differentiation and low levels of recurrent gene flow through seeds among populations. Nested clade phylogeographic analysis of chlorotypes suggests that population genetic structure in C. taliensis has been affected by habitat fragmentation in the past. However, the detection of a moderate nrDNA population subdivision (GST?=?0.222; NST?=?0.301) provided the evidence of efficient pollen-mediated gene flow among populations and significant phylogeographical structure (NST?>?GST; P?

SUBMITTER: Liu Y 

PROVIDER: S-EPMC3495649 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature