湖南江永普通野生稻原位和异位保存种质的SSR多样性差异

SSR Diversity of in-situ and ex-situ Conserved Oryza rufipogon Populations in Jiangyong County of Hunan Province

用48对SSR引物对湖南江永普通野生稻异位保存和原位保存居群进行了遗传多样性分析。48对SSR引物在异位保存和原位保存群体中分别检测出166和119个等位基因，平均每对引物检测到的等位基因数分别为3．55和2．60，多态位点百分率为99．4％和95．2％，平均等位基因观察数为1．99和1．95，平均有效等位基因数为1．428和1．508，Nei基因多样性指数为0．272和0．304；原位保存居群遗传变异大，但异位保存样本中发现新的变异单株。江永野生稻原位保存4个亚居群（G4—1、G4—2、G4—3、G4—4）的遗传分化系数为0．156～0．935，平均0．434，江永野生稻4个亚居群间变异量占总变异量的比值差异较大，总变异的43．4％存在于亚居群之间。除G4—2亚居群外，原位保存各亚居群内基因多样性大于亚居群间基因多样性，4个亚居群内基因多样性水平从高至低的顺序为G4—1〉G4—3〉G4—4〉G4—2。

The genetic diversity of Jiangyong wild rice （Oryza rufipogon） populations in ex-situ and in-situ conservation was studied by using SSR assay. The 48 SSR markers showed polymorphic bands. A total of 166 and 119 alleles were detected in the ex-situ （G3） and in-situ （G4） populations, with the average of 3.55 and 2.60 per marker, respectively. In G3 and G4 populations, the percentage of polymorphic loci （P） were 99.4 % and 95.2 %, the mean number of observed alleles （A） 1.99 and 1.95, the mean effective number of alleles （Ae） 1. 428 and 0. 508, and gene diversity （He） 0. 272 and 0.304, respectively. It indicated that richer genetic variation existed in G4, but some new variants were found in G3, not in G4. Furthermore, 43.4% of total variation in G4 was found among the subpopulations, with a mean coefficient of gene differentiation （Gst） 0. 434 in a range of 0. 156-0. 935 among the four subpopulations （G4-1, G4-2, G4-3, G4-4）. Beside G4-2 subpopulation, more gene diversity existed within subpopulations than between subpopulations in the in-situ populations, and the order of gene diversity was G4-1〉G4-3〉G4-4〉G4-2.