Phylogeography of Tamarix austromongolica Based on the Sequences of Chloroplast and Nuclear Gene Fragments

【Objective】 Tamarix austromongolica is an endemic species distributed along the Yellow River Basin in China. The purpose of this study was to explore the genetic structure and diversity of the T. austromongolica populations.【Method】 Using the chloroplast DNA fragment( trn Q-rps16) and the nuclear gene fragment,the Internal Transcribed Spacer( ITS) to study the genetic diversity,the genetic structure and the historical dynamics of 266 individuals in seventeen populations of T. austromongolica distributed in the Yellow River basin of China by PCR amplification and sequencing.【Result】 Four chloroplast haplotypes in 207 individuals and 32 nuclear haplotypes in 232 individuals were detected. The genetic diversity of T. austromongolica based on chloroplast gene analysis was low( HT= 0. 13),however,the genetic diversity of nuclear genes was high( HT= 0. 82). The AMOVA analysis of chloroplast gene( cpDNA) and nuclear gene( nDNA) fragments showed that the genetic variation of T. austromongolica populations mainly occu