鸭茅种质遗传变异及亲缘关系的SSR分析

Genetic variation and relationship in orchardgrass (Dactylis glomerata L.) germplasm detected by SSR markers

利用SSR标记技术对来自世界5大洲的53份鸭茅(Dactylis glomerataL.)材料的遗传变异及亲缘关系进行了研究。用筛选的15对引物对53份材料的DNA进行PCR扩增,获得下述结果:(1)15个位点共检测到127个等位基因,每个位点等位基因变幅为5～12个,平均为8.5个,多态性位点率(P)平均为95.21%;多态性信息含量(PIC)范围为0.30(A04C24)到0.44(A01F24),平均为0.36;(2)材料间遗传相似系数(GS)范围在0.43到0.94之间;地理类群间的GS值在0.73到0.91间,其中亚洲(P,90.55%)和欧洲(P,86.61%)类群遗传多样性丰富,表明供试鸭茅种质具有丰富的遗传变异;(3)根据研究结果进行聚类分析和主成分分析,可将53份鸭茅材料分成5大类,来自相同洲的材料能聚为一类,呈现出一定的地域性分布规律。

Genetic variation and relationship of 53 accessions of D. glomerata collected from 5 continents were analyzed using simple sequence repeat （SSR） molecular markers with 15 SSR primer pairs. The following results were obtained. （1） A total of 127 alleles were detected at 15 loci. The number of alleles per locus ranged from 5 to 12, with an average of 8.5. The rate of polymorphic sites （P） was 95.21%; the polymorphic information content （PIC） ranged from 0.30（A04C24）to 0.44（A01F24）with an average of 0.36. （2） The genetic similarity （GS） among all accessions ranged from 0.43 to 0.94, for all geographical groups GS ranged from 0.73 to 0.91, and high genetic diversity was observed in Asia （P, 90.55%） and Europe （P, 86.61%） groups. These results suggested that there was rich genetic diversity among all orchardgrass accessions tested. （3） Based on the cluster and principal component analyses, 53 accessions could be divided into five groups according to the nearest phylogenetic relationship, and accessions from the same continent were classified into the same group associated with their geographical distributions.