利用微卫星标记比较云南元阳哈尼梯田两个不同时期种植的水稻地方品种的遗传多样性

 为了揭示云南元阳哈尼梯田两个不同时期种植的水稻地方品种的遗传多样性，以元阳哈尼梯田过去种植（20世纪70年代收集于元阳县，现保存于种质库）的72个和当前种植的76个品种为材料，采用48个SSR分子标记进行多态性、遗传相似性和聚类分析。平均每个标记检测到的等位基因数、有效等位基因数、位点多态信息含量和基因型多样性指标在过去与当前的品种间，差异均未达显著水平。共有24个SSR标记的52个等位基因位点在过去与当前种植的品种中存在差异，其中，有18个SSR标记的32个等位基因位点在当前的品种中未检测到，同样，有16个SSR标记的20个等位基因位点在过去的品种中未检测到。基于48个SSR分子标记的平均遗传相似性系数，当前种植的品种为03340，过去为03313，过去与当前的品种分别在遗传相似性系数0203和0174处分为籼、粳两个亚种群。表明元阳哈尼梯田水稻地方品种经过30多年的自然与人工选择，虽有部分等位基因位点发生了变异，但仍保留了原有的遗传多样性；元阳哈尼梯田水稻地方品种存在明显的籼、粳分化。元阳哈尼梯田及其水稻地方品种是研究稻作籼粳演化的理想基地和材料。

Comparison of Genetic Diversity of Rice Landraces Planted in Two Periods in Hani's Terraced Fields in Yuanyang County, Yunnan Province, China Using Microsatellite Markers

To compare the genetic diversity of  rice landraces  in different  periods polymorphism, genetic similarity and cluster   analyses were conducted with 148  rice landraces by using 48 SSR markers.  The materials included  72 landraces collected during the 1970s (past grown landraces) and 76   grown during the past decade (current grown landraces) in Hani′s terraced fields in  Yuanyang County, Yunnan Province. The results showed that the differences between the two periods in all  indices,    including average number of alleles, effective number of alleles, locus polymorphism information content  and genotype diversity  were not significant. Furthermore,  52 alleles of 24 SSR markers differed between the past grown  and the current grown  landraces, among which 32 alleles of 18 SSR markers were not detected in the current grown  landraces and 20 alleles of 16 SSR markers were not detected in the past grown  landraces.  The average genetic similarity coefficient of the current grown  landraces was 03340, and that of the past grown  landraces was 03313.   The current grown and  past grown  landraces were divided into japonica and indica subspecies at the genetic similarity coefficient of 0174  and 0203,  respectively. These results indicated that for   more than 30 years′  natural and artificial selection, there were variations  in some of the allele  locus of the   rice landraces  from Hani′s terraced fields with high genetic diversity. In addition, the indica japonica subspecies differentiation was obvious in the landraces from Hani′s terraced fields in Yuanyang, and the differentiation seemed to be ongoing, indicating that Hani′s  terraced fields and the   rice landraces might be ideal tested field  and materials for the  study of   indica japonica subspecies evolution.