基于叶绿体DNA片段序列的臭柏种群遗传结构分析

Genetic Structure Analysis of Juniperus sabina L.Population Based on Chloroplast DNA Fragment Sequence

本实验选取内蒙古自治区及其附近地区分布的臭柏9个野生种群(共221个个体)为材料,对其叶绿体DNA的非编码区序列trn L-trn F,trn S-trn G和trn D-trn T进行测序,通过分析叶绿体DNA序列变异来获得单倍型类型。发现序列总长度为2 068~2 073 bp,总共观察到了三处变异位点,将这三个变异位点组合后共获得了四个单倍型:H1、H2、H3和H4,其中H1单倍型分布最广。物种水平上单倍型多样性(Hd)指数为0.072,核苷酸多样性(π)指数为0.000 14;种群水平上Hd指数介于0~0.239,π指数介于0~0.000 63。种群间基因分化系数Gst为0.045、固定指数Fst为0.071。研究结果表明臭柏种群间遗传变异较低,种群内遗传变异较高。

In this experiment,9 Juniperus sabina wild populations（221 individuals） distributed in Inner Mongolia Autonomous Region and its surrounding areas were selected as experimental materials.The non-coding region trn L-trn F,trn S-trn G and trn D-trn T of chloroplast DNA were sequenced and the haplotype type was obtained by analyzing chloroplast DNA sequence variation.The total length of the sequence was 2 068~2 073 bp.Three mutations were observed.Four haplotypes were obtained after the combination of these three mutations： H1,H2,H3 and H4,where H1 haplotype was the most extensively distributed.In species level,haplotype diversity（Hd）index was 0.072,nucleotide diversity（π） index was 0.000 14.In population level,Hd index was between 0~0.239 and π index was between 0~0.000 63.The genetic differentiation coefficient Gst was 0.045 and the fixed index Fst was 0.071.The results showed that the genetic variation among population of Juniperus sabina L.in Inner Mongolia and surrounding areas was low,and the genetic variation in populations was high.