用微卫星标记评估中国水稻主栽品种的遗传多样性

【目的】为正确评估中国水稻(Oryza sativa L.)主栽品种的遗传多样性提供依据。【方法】应用位于水稻)12条染色体上已筛选的24个微卫星(simple sequence repeats, SSR)标记组合（每条染色体2个），分析63个主栽常规稻品种和杂交稻组合亲本(2002年推广面积达6.67×104 ha（100万亩）)的遗传变异。【结果】共检测到135个等位基因，平均每个标记5.6个；多态性频率（frequency of polymorphisms, FP）变动范围为0.486～0.840，平均0.682。水稻恢复系比保持系/不育系遗传差异大；与常规籼稻品种相比，常规粳稻品种的遗传多样性较低。聚类分析表明，中国籼稻品种主要来自华南稻区和长江流域稻区，粳稻品种则分布于北方稻区和太湖流域(江苏和浙江省)，表现出明显的地域分布特点。【结论】作者认为，应用微卫星标记所作的中国水稻品种聚类分析与传统系谱分析趋势一致，结果更为精确。

Microsatellite Marker Evaluation on Genetic Diversity of the Major Commercial Rice Varieties in China

To reveal their genetic relationship on the molecular level of the major rice varieties and parental lines of hybrid rice in China, amplification of DNA from all 63 tested lines are successfully made using a set of 24 SSR (Simple sequence repeats) primer pairs located along 12 chromosomes in rice, with two pairs on each chromosomes, we detected a total of 135 alleles, whose number of per primer pairs ranged from 2 to 9, with an average 5.6, and FP（Polymorphisms frequency）values between 0.486-0.840, with an average of 0.682. Cluster analysis showed that indica subspecies include maintainer lines (lines that can maintain male sterile, group Ⅰ) and restorer lines (lines that can restorer male sterile, group II), which separately distributed in South China and the Changjiang River area, whereas Group Ⅲ corresponded to the japonica subspecies were also divided into two subgroups（GⅢ-1 and GⅢ-2）, which grown in North China and Jiangsu-Zhejiang provinces respectively. This indicated that geographic distribution is one of the major characteristics of rice varieties. The average genetic similarity of the indica varieties/lines (0.388) was significantly lower than that of japonica varieties (0.638), showing a higher level of genetic diversity of indica. Also restorer lines have a higher genetic diversity than maintainer lines. On the basis of the data we conclude that the genetic relationship constructed by SSR markers was identical and more accurate, compared with that by the pedigree analysis.