【摘要】 【目的】评价太湖流域粳稻地方品种的遗传多样性。【方法】利用58对SSR引物,对基于主要农艺性状构建的太湖流域粳稻地方品种核心种质库的122个品种进行DNA水平的多态性分析,并与15个现代育成品种做比较。【结果】(1)地方品种群体中53个SSR位点共检测到216个等位片段,每个多态性位点等位片段数的变化范围为2～7个,平均为4.08个;71.7%的SSR位点具有3个以上等位片段;53个位点PIC值的变化范围为0.031～0.773,平均为0.413;Nei’s基因多样性指数He为0.378;品种间遗传距离平均为0.419;12条染色体中,第5染色体平均等位片段数最多,第11染色体平均PIC值最大。(2)现代育成品种群体检测到的等位片段数、位点PIC值、Nei’s基因多样性指数和品种间遗传距离均比地方品种群体相应值小,地方品种的遗传多样性大于现代育成品种。(3)聚类分析显示,在遗传相似系数0.63处,地方品种和现代育成品种可以明确区分开来。【结论】太湖流域粳稻地方品种具有丰富的遗传多样性,且与现代育成品种有较大的遗传差异,可用以拓宽育成品种的遗传基础。更多还原

【Abstract】 【Objective】Genetic diversity of japonica rice landraces (Oryza sativa L.)from Tai Lake region was investigated at DNA level. 【Method】One hundred and twenty-two varieties, which come from a core collection established on the basis of main agronomic traits, were evaluated by means of fifty eight SSR markers distributed over whole rice genome. As a control, fifteen modern cultivars from the same region were compared with these landraces to determine their relationship. 【Result】In landrace population, a total of 216 alleles were detected at fifty-three SSR loci, and the number of alleles per marker ranged from two to seven,with an average of 4.08. SSR loci with more than three alleles accounted for 71.7 percent of total SSR loci studied. The average PIC value of SSR primer was 0.413, with a range from 0.031 to 0.773. Nei’s gene diversity index (He) was 0.378, and average genetic distance (GD) among varieties was 0.419. Among the 12 chromosomes, chromosome 5 showed the greatest value in average allele number, while chromosome 11 showed the highest average PIC value. At the same time, the genetic diversity of landrace population was higher than that of modern cultivar population according to total allele number detected, PIC value, He, and GD among varieties in each population. Clustering analysis with UPGMA method based on genetic similarity coefficients showed that all landraces in Tai Lake region could be well separated, while with genetic similarity coefficient of 0.63,modern cultivars and landraces could be clearly distinguished. 【Conclusion】Rich genetic diversity exists in japonica rice landraces from Tai Lake region. There are great genetic difference between landrace and modern cultivar population. The genetic diversity could be utilized in broadening genetic basis of japonica rice cultivars to be bred in future.更多还原