结缕草属种质资源EST-SSR遗传多样性分析

Genetic Diversity Analysis of Zoysia willd.Accessions by EST-SSR Markers

本研究以43份不同来源的结缕草属种质为材料,利用表达序列标签-简单重复序列(Expressed Sequence Tag-Simple sequence repeat,EST-SSR)引物对其进行遗传多样性分析。结果表明:从125对EST-SSR引物中筛选出30对能稳定扩增、条带清晰的引物;共检测到124个标记,平均每对引物检测到4个,多态性标记有108个,多态性位点百分率为88.60%;种质间遗传相似性系数为0.530~0.864,平均为0.711;共检测到104个观察等位基因,平均每对引物检测到3个;有效等位基因数范围为0~5,平均为3;Shannon信息指数变化范围为0~1.593,平均为0.940。Nei’s基因多样性指数范围为0~0.793,平均为0.541;在遗传相似性系数为0.800时,利用非加权组平均法(Unweighted pair-group method with arithmetic means,UPGMA)法将43份种质划分为4个类群,聚类结果与种质地理位置有一定的关联,但联系不紧密。本研究结果表明43份种质的遗传多样性处于上等水平,EST-SSR标记能有效地评价结缕草属种质的遗传差异,为结缕草属种质资源的鉴定评价及分子标记辅助育种提供参考依据。

In the present study,43 Zoysia willd.accessions from different sources were used to detect the genetic diversity using Expressed sequence tag-simple sequence repeat(EST-SSR)primers.The results showed that 30 pairs of primer from the original 125 pairs of primer were selected based on the polymorphic,clear and reproducible bands amplified by them.A total of 124 bands were amplified by 30 primer pairs from 43 accessions with 4 bands per primer pairs,and 108(88.60%)out of them were polymorphic.The genetic similarity coeffcients(GSC)among the 43 accessions ranged from 0.530 to 0.864 with an average of 0.711.A total of 104 observing alleles were amplified by 30 pairs of primer from 43 accessions with 3 observed alleles per pairs of primer.The range of effective number of alleles was 0 to 5 with an average of 3.The range of shannon information index was 0~1.593 with an average of 0.940.The Nei’s genetic diversity index was 0~0.793 with an average of 0.541.Cluster analysis conducted by the unweighted pair-group method with arithmetic averages(UPGMA)separated the 43 accessions into 4 groups when the genetics similarity coefficient was 0.800.The clustering results were somewhat correlated with the geographical location of the accessions,but not closely related.The results indicated that the genetic diversity of Zoysia willd.accessions was rich,which laid a foundation for the identification and evaluation of Zoysia willd.accessions and molecular marker-assisted breeding.