锥栗优良无性系遗传多样性的EST⁃SSR分析

EST⁃SSR analysis of the genetic diversity of superior clones of Castanea henryi

为促进锥栗新品种的选育、种质资源的鉴定和锥栗产业的健康发展,以福建省建瓯市栽培的22个锥栗优良无性系为研究对象,利用开发的6对多态性表达序列标签-简单重复序列(EST⁃SSR)引物对其遗传多样性进行研究,并构建指纹图谱。结果表明,22个锥栗无性系平均每对引物的等位基因数为2.667,平均有效等位基因数为2.038,平均观测杂合度为0.349,平均期望杂合度为0.447,平均Shannon信息指数为0.721,平均多态性位点数为11.500,平均多态性信息含量为0.434,表明锥栗无性系遗传多样性较高。遗传相似系数变化范围为0.754~1.000,平均值为0.856;在遗传相似性系数为0.860处,可将其划分为5个大类:第Ⅰ类仅包括HL19;第Ⅱ类包括HL5、HL6、HL8、HL21;第Ⅲ类包括HL17、HL18;第Ⅳ类包括HL12、HL13;第Ⅴ类包括HL1、HL2、HL3、HL4、HL7、HL9、HL10、HL11、HL14、HL15、HL16、HL20、HL22。利用3对多态性引物,共构建了22个锥栗无性系的指纹图谱。

To promote the selection of new Castanea henryi varieties,the identification of germplasm resources,and the healthy development of the industry,the genetic diversity of 22 excellent clones cultivated in Jian’ou city,Fujian province,were investigated using six pairs of polymorphic EST⁃SSR primers,and the fingerprints were constructed.Results showed that the average number of alleles per primer pair was 2.667,average number of effective alleles was 2.038,average observed heterozygosity was 0.349,average expected heterozygosity was 0.447,average Shannon′s information index was 0.721,average number of polymorphic loci was 11.500,and average polymorphic information content was 0.434,indicating high genetic diversity.The genetic similarity coefficient varied from 0.754 to 1.000,with an average value of 0.856.At the genetic similarity coefficient of 0.860,it could be divided into five major classes.ClassⅠincluded only HL19.ClassⅡincluded HL5,HL6,HL8,and HL21.ClassⅢincluded HL17 and HL18.ClassⅣincluded HL12 and HL13.ClassⅤincluded HL1,HL2,HL3,HL4,HL7,HL9,HL10,HL11,HL14,HL15,HL16,HL20,and HL22.Fingerprints of 22 clones were constructed using three pairs of polymorphic primers.It provided a reference for the selection of parents and superior germplasms.