基于SSR标记的苔草种质遗传多样性分析

苔草属(Carex L.)植物为莎草科多年生草本,在园林绿化、畜牧业生产、生态修复等方面发挥着越来越重要的作用。为了了解新西兰苔草品种间的遗传多样性及与国内苔草的地域差异,对其进行分子标记分析。本研究利用筛选得到的10对SSR引物对12份苔草材料(包括10份新西兰引进品种)进行遗传多样性分析,结合聚类分析等揭示苔草材料之间的遗传多样性。结果显示,10对SSR引物最终扩增出91条多态性条带,据此建立的指纹图谱显示Ctcp016引物可以一次性鉴别12份苔草样品;多态性比率为97.8%,平均每条引物扩增出8.27条,多态性信息含量(PIC)在0.140~0.260之间,平均多态性信息含量为0.220,平均遗传距离值为0.428;12份参试苔草资源的观测等位基因数(Na)、有效等位基因数(Ne)、基因多样性指数(H)以及Shannon信息指数(I)平均值分别为1.976、1.350、0.226、0.368,表明各苔草样品之间的遗传多样性处于较高水平;非加权组平均(UPGMA)聚类系统发生树在遗传距离为0.428时可将12份苔草分为3类,地域对苔草遗传信息无明显影响。本研究表明利用SSR标记可以有效地对苔草遗传多样性及群体结构进行分析,并可构建苔草遗传图谱,为以后的研究提供丰富的标记来源,有助于推动苔草分子标记辅助育种工作,为进一步开发利用苔草资源提供帮助。

Genetic Diversity of Carex Germplasm Detected by SSR Molecular Markers

Carex L.,one of the largest genera in the Cyperaceae,which plays an increasingly important role in landscaping,animal husbandry production,ecological restoration and other aspects.In order to figure out the genetic diversity of Carex species in New Zealand and the regional differences with species in China,we used the simple sequence repeats(SSRs)markers of Carex species for establishing its molecular marker system.In this study,10 pairs of SSR primers screened were used to analyze the genetic diversity of 12 Carex materials(including 10 imported varieties from New Zealand),and cluster analysis was used to reveal the genetic diversity among Carex materials.The results showed that 10 pairs of SSR primers finally amplified 91 polymorphic bands,and the established fingerprint showed that Ctcp016 primer could identify 12 Carex samples at one time.The polymorphism rate was 97.8%,the average number of amplified primers was 8.27,and a polymorphic information content(PIC)ranged from 0.140 to 0.260,with an average of 0.220.and the average distance value was 0.428.The average number of observed alleles(Na),effective alleles(Ne),gene diversity index(H),and Shannon information index(I)of the 12 species of Carex germplasm was 1.976,1.350,0.226,0.368,respectively,indicating that the genetic diversity among the samples is at a high level.The Unweighted Pair Group Method with Arithmetic Mean(UPGMA)cluster phylogenetic tree could divide 12 Carex into three groups when the genetic distance was 0.428,and the region had no significant effect on the genetic information of Carex.In conclusion,these markers can effectively analyze the genetic diversity,population structure and build DNA fingerprint of Carex,providing a rich source of markers for subsequent studies.It will also contribute to Carex molecular marker-assisted breeding projects,and pave the way for further development and utilization of Carex resources.