利用ISSR分子标记对25个烟草种质资源的遗传多样性分析

Genetic Diversity Analysis of 25 Tobacco Germplasm Resources by ISSR Molecular Marker

[目的]利用ISSR分子标记研究烟草遗传的多样性。[方法]利用ISSR分子标记对25个烟草种质资源进行了遗传多样性分析。[结果]从50条ISSR引物中共筛选出5条引物，对25份材料烟草基因组DNA进行有效扩增，共扩增出100个位点，其中有76个多态性位点，多态性比率为76．0％。用NTSYSpc-2．10e软件计算烟草种质间的Jaccard遗传相似系数，25种烟草种质之间的遗传相似性系数界于0．313～0．938，平均遗传相似性系数为0．737。野生烟与栽培烟草相似系数较低，说明它们之间存在较高的遗传多样性。利用UPGMA进行的系统聚类分析表明，25个烟草种质资源可划分成2组，3个野生烟聚成一类，22个栽培烟草种质聚成另一大类。[结论]供试栽培烟草的遗传多样性相对较低．迫切需要拓宽栽培烟草的遗传基础。

[ Objective] The aim was to use ISSR molecular marker to study the genetic adversity of tobacco. [ Method]The genetic diversities of 25 tobacen gerrnplasm resources were analyzed by ISSR molecular marker. [Result] 5 primers were screened out from 50 ISSR primers totally to amplify the tobacco genome DNAs of 25 materials effectively and 100 sites were amplified out totally, including 76 polymorphism sites with polymorphism rate of 76%. The Jaccard genetic similarity coefficients among tobacco gennplasms were calculated by using NTSYSpc - 2.10e software. The genetic similarity coefficients among 25 tobacco germplasms were between 0. 313 and 0.938 and the average genetic similarity coefficient was 0.737. The similarity coefficient between wild and cultivated tobaccos was lower, indicating that there was higher genetic diversity between them. The systematical cluster analysis conducted with UPGMA showed that 25 tobacco germplasm resources could be divided into 2 groups, 3 wild tobaccos gathered to be a category and 22 cultivated tobacco germplasms gathered to be another big category. [ Conclusion] The genetic diversity of tested cultivated tobacco was relatively low and it was urgent to develop genetic base of cultivated tobacco.