中国西南区鸭茅种质遗传变异的SSR分析

Genetic variation of Dactylis glomerata germplasm from Southwest China detected by SSR markers

用SSR标记对来自中国西南地区（四川、云南、贵州、重庆）的11份鸭茅种质的110个单株进行遗传多样性研究。结果表明，1）21对引物共扩增出多态性条带143条，平均每对引物扩增出6．8条，多态性条带比率（PPB）达90．7％；多态性信息含量（PIC）范围为0．17（A01F24）～0．45（A01E02），平均为0．33；Shannon多样性指数（Ⅰ）范围在0．0463～0．3477，表明供试鸭茅种质具有丰富的遗传多样性。2）AMOVA分析表明，63．93％的遗传变异存在于种质内部，种质间变异仅为21．93％，二倍体与四倍体鸭茅群体间遗传差异不显著。3）对各地理类群基于Nei氏无偏估计的遗传一致度可将11份鸭茅分为2大类：来自重庆和贵州的3份二倍体材料YA2006—3、YA2006—4和YA02—101聚为Ⅰ类，其余8份材料聚为Ⅱ类，来自相同或相似生态地理环境、相同倍型的材料基本聚为一类，呈现出一定的相关性。

Simple sequence repeat （SSR） molecular markers were applied to detect the genetic variation of 110 individuals of 11 Dactylis glomerata accessions from Southwest China（Sichuan province, Yunnan province, Guizhou province and Chongqing city）. 1） 21 primer pairs were selected for SSR analysis and 143 polymorphic bands were found with an average of 6.8 bands per primer pair. The percentage of polymorphism bands （PPB） was 90.7%, the polymorphism information content （PIC） ranged from 0.17（A01F24） to 0.45（A01E02） with an average of 0.33, and the Shannon＇s information index of diversity （Ⅰ） ranged from 0. 046 3 to 0. 347 7, showing considerable genetic diversity between all the accessions. 2） The AMOVA analysis showed considerable genetic variation within accessions （63.39%） rather than between them （21.93%）. There was no significant genetic variation between diploid and tetraploid groups. 3） UPGMA clusters based on average Nei＇s genet ic identity divided 11 accessions into two groups： 3 diploid accessions （YA2006-3, YA2006-4, YA02-101） collected from Chongqing and Guizhou were classified into group Ⅰ and the remaining 8 accessions were classified into group Ⅱ. In most cases, materials from the same region and ploidy level were in the same group thus showing a geographical distribution of genetic diversity of the tested materials.