ISSR分子标记技术在分析玉米自交系遗传关系研究中的适用性

利用ISSR分子标记技术对59份玉米自交系和1份大刍草材料进行遗传多样性分析.21对ISSR引物共扩增出475条不同位置的带,平均22.6条;多态性带469条,平均22.3条,百分率高达98.7%;不同引物的多态性信息指数(PIC)在0.84～0.94之间.60份材料的遗传相似系数在0.23～0.48之间.经聚类分析,可将这些材料分成两大组,共9个亚组,并且在一定程度上与血缘和系谱是一致的,也存在一些例外.结果表明,ISSR标记尽管可以用于进行遗传多样性分析,但并不是最好的分子标记类型.综合考虑不同的分子标记类型的优缺点,认为ISSR标记在遗传研究较少的作物上应用潜力较大.

Suitability of ISSR Markers in Analysis of Genetic Relationships among Maize Inbred Lines

The genetic diversity of 59 maize inbred lines and one teosinte accession was analyzed by using ISSR markers. With 21 ISSR primers, totally 475 alleles were detected among which 469 were polymorphic, and the average number of alleles for one primer was 22.6. Polymorphic information content (PIC) ranged from 0.84 to 0.94. The similarity coefficient of 60 accessions ranged from 0.23 to 0.48. Cluster analysis based on ISSR data showed that the accessions could be categorized into two groups and further 9 sub-groups,to some extent in accordance with the pedigrees of the entries and with some exceptions. Therefore, the present study indicated that ISSR marker was not the best marker system for assessment of genetic diversity although it might reveal genetic relationships among accessions. It was suggested that ISSR be used for assessment of genetic diversity in under-researched or neglected crops.