野生狗牙根种质资源SRAP与SSR的遗传多样性

【目的】为指导种质资源的引进和利用及选育优质狗牙根新品种提供科学依据。【方法】采用SRAP和SSR两种分子标记方法相结合，对52份野生狗牙根材料进行遗传多样性分析。【结果】①利用4个表型差异显著的野生狗牙根对SRAP的150对引物组合及SSR的200对引物组合进行扩增，分别筛选出有效引物组合各18对，SRAP和SSR扩增总条带分别为236和346条，多态性条带206和255条，平均每对引物扩增出多态性条带各11.4和14.17条，多态性位点百分率分别为87.29%和73.70%；②两种标记结合进行聚类分析，当GS=0.68时，可将所有供试材料分成5个组群；当GS=0.78时，可将第V个组群分成6个小组，大部分来自相同或相似生态地理环境的材料聚为一类；③基于聚类分析，可将供试材料分为8个生态地理类群，据各类群间的Nei氏遗传一致度和遗传距离的无偏估计值表明，生态地理环境相似的地理类群遗传距离较小；④SRAP和SSR标记之间具有显著的相关性，且相关性较高。【结论】野生狗牙根有丰富的遗传多样性，其聚类和生态地理环境有一定的相关性。

Genetic Diversity of Cynodon Dactylon Germplasm by SRAP and SSR Markers

【Objective】 The aim of the study is to guide the introduction and utilization of germplasm resources,to provide a scientific basis for molecular marker-assisted breeding and to select parents for breeding programs accurately.【Method】 In the study,SRAP and SSR markers were employed to investigate the genetic diversity and relationships of 52 wild accessions of Cynodon dactylon.【Result】 In a preliminary experiment,four accessions markedly distinct in phenotype were used to screen 150 pairs of SRAP primers and 200 pairs of SSR primers.Finally,18 pairs of SRAP and SSR primers were selected and used for the present study.Eighteen primer pairs of SRAP and SSR produced a total of 236 and 346 bands,including 206 and 255 polymorphic bands,averaged 11.4 and 14.17 polymorphic bands per primer pair.The percentages of polymorphic bands were 87.29% and 73.70% in average.Combined the both markers with cluster analysis,when the GS is 0.68,the 52 accessions were classified into five major groups,GS is 0.78,the part V is divided into six groups.The accessions from the same origin frequently were clustered into one group.By the cluster analysis,the tested materials could be divided into eight eco-geographical groups.The Nei’s unbiased measures of genetic identity and genetic distance among eight eco-geographical groups showed the small genetic distance of geographic groups which have the similar eco-geographical environment.The data implied a correlation among the wild resources,geographical and ecological environment,which showed a significant relationship with the origined regions of accessions.【Conclusion】 The substantial genetic diversity was identified among the Cynodon dactylon germplasm.Furthermore,the results of cluster were related with the ecogeographical condition.