基于ISSR分子标记的27种栎属树种亲缘关系研究

Study on genetic relationship of 27 Quercus species based on ISSR molecular marker

本文对栎属27个树种采用ISSR分子标记技术和非加权平均距离法(UPGMA)进行亲缘关系和聚类分析,结果表明:12条引物共扩增出140个位点,其中有115个是多态性位点,比率为82.14%,引物UBC864和UBC812分别扩增16、9个位点;27种栎属树种的观测等位基因数为1.8071,有效等位基因数为1.3688,Nei′s基因多样性指数为0.2319,Shannon′s多样性指数为0.3621,这表明栎属树种的遗传多样性较高。27种栎属树种遗传一致度的变化范围在0.5429~0.9000之间,北美红栎与月桂叶栎遗传一致度最大,为0.9000;栓皮栎与椭圆果栎遗传一致度最小,为0.5429。27种栎属树种被分为5大类群,其中:短柄枹栎和白栎、北美红栎与月桂叶栎、南方红栎与柳叶栎等聚在一起,与传统形态分类一致;小叶栎与娜塔栎分为一类,与传统形态分类不一致。部分聚类结果与形态分类并不一致,具体原因还需进一步研究;聚类未完全按照来源地进行分组,材料之间存在一定交叉。本研究利用ISSR分子标记技术可很好的区分27种栎属树种,并得出其多态位点百分率,遗传距离、遗传一致度等一系列数据,有助于进一步了解栎属树种的遗传基础,揭示其亲缘关系,为栎属树种杂交育种提供参考。该技术也可应用到栎属新品种鉴定、杂交亲本的选配与新种质资源的划分等领域,应用前景广阔。

Genetic diversity and genetic relationship analysis of 27 Quercus specieswere carried out to provide theoretical basis for cross breeding of Quercus.The molecular marker technique of inter-simple sequence repeat(ISSR)and unweighted pair-group method with arithmetic means(UPGMA)were used to study the genetic diversity and genetic relationship of 27species.The 12 primers amplified a total of 140 sites,115 of which were polymorphic sites,accounting for 82.14%of the total number of sites,and 16 of the UBC864 sites were amplified.The amplification site number of the primer UBC812 was 9.The observed allele number of 27 Quercus species was 1.8071,the effective allele number was 1.3688,Nei's gene diversity was 0.2319,and Shannon's information index was 0.3621,indicating the higher genetic diversity.The genetic identity of Quercus species was 0.5429~0.9000.The genetic identity of Quercus rubra and Quercus laurifolia was the highest as 0.9000.The genetic identity between Quercus variabilis and Quercus ellip-soidalis was the smallest as 0.5429.27 Quercus species divided into 5 groups,of which Quercus serrata and Quercus fabri,Quercus rubra and Quercus hemisphaerica,Quercus falcata and Quercus phellos,etc.were grouped together,consistent with the traditional morphological classification.Quercus chenii and Quercus nuttallii were divided into one class,which was inconsistent with the traditional morphological classification,and the specific reasons should be further studied.Some clustering results were inconsistent with morphological classification,and the specific reasons need to be further studied.The clustering was not completely grouped according to the source,and there was a certain crossover between the materials.This study using ISSR molecular marker techniques could be suitable for 27 kinds of oak tree species,and it was concluded that the percentage of polymorphic bands,genetic distance and genetic identity and a series of data were helpful to further understand the genetic basis of oak is a tree species,revealing its genetic relationship.The technology could also be applied to a new variety identification,the division of matching of hybrid parent and the new germplasm resources,and other fields of oak with broad application prospect.