【作者】 应杰政；

【导师】 薛庆中；

【作者基本信息】 浙江大学 ， 作物遗传育种， 2006， 硕士

【摘要】 特异性、一致性和稳定性(distinctness,uniformity and stability,DUS)的测试是植物新品种必须具备的特征,也是品种注册和新品种保护的前提。用于DUS测试的主要性状是植物的形态性状及生理特性。这些性状大多是数量性状,受多基因控制,易受环境影响。此外,随着注册品种数量的不断增多,传统的DUS测试耗时又费用昂贵,并难以对新品种与所有已知品种进行有效比较。为克服以上困难,本项研究选择在植物品种DUS测试和品种鉴定研究中应用得最为广泛的分子标记——微卫星标记,分析了我国主栽水稻品种的遗传一致性、多样性和遗传关系,并构建了我国主栽水稻品种的微卫星数据库,结果如下: 1、应用微卫星标记评估中国主栽水稻品种的一致性。提出5个微卫星标记组合可供清晰、有效地检测水稻品种内遗传变异,对41个有多个来源的水稻品种SSR测试,结果表明,同一品种名称来源间仍有18个(43.90%)品种存在差异,因此在构建水稻品种微卫星数据库时,必须慎重选择取样来源。为准确评估我国水稻主栽品种的一致性,选择了11个代表性水稻品种或杂交稻组合亲本作较大样本分析(50个单株),每个微卫星标记检测到的异质率有差异,变化幅度为0.36-5.45%。各个我国主栽水稻品种在5个微卫星标记上的不一致率为0-10.0%,平均1.67%,11个品种中完全一致的品种有6个(54.55%),在微卫星标记上的不一致率通常都不超过5%。 2、中国主栽水稻品种的遗传多样性分析。选用分布于水稻(Oryza sativa L.)12条染色体的24对SSR(simple sequence repeats)引物,每条染色体2对,检测分析了63个我国主栽水稻品种及杂交稻亲本。63份水稻材料在24个座位都成功扩增,共检测到135个等位基因,每对引物扩增得到2-9个等位基因,平均每个座位5.6个等位基因。微卫星标记的多态性频率(frequency of polymorphism,FP)变动范围0.486-0.840,平均0.682。通过对每个微卫星标记的各个等位基因的命名,构建了63份材料的微卫星数标记数据库。同时,根据检测得到的各材料间的遗传差异,评估了我国主栽水稻品种的遗传多样性与遗传关系。聚类分析结果表明常规水稻品种有明显的地理分布特点,籼稻品种主要分为华南稻区和长江中下游流域稻区,而粳稻品种则分布为北方粳稻区和苏浙粳稻区。与粳稻相比,籼稻品种的遗传背景较广,有较高的遗传多样性。不育系/保持系遗传背景单一,遗传变异较小,恢复系材料相对于不育系/保持系而言,遗传差异较大。结果表明应用微卫星标记所作的聚类分析结果与传统系谱分析趋势一致,并更为精确。更多还原

【Abstract】 DUS criteria are used world-wide for the granting of Plant Breeders’ Rights (PBR) and variety registration. The tests are mainly based on morphological and physiological markers. Many of the characters are multi-genic, quantitative or continuous characters and their expression can be altered by environmental factors. Furthermore, because the number of registered varieties increases over time, the traditional method of DUS testing is time-consuming and expensive, and it is impossible to check efficiently each new variety against all varieties of common knowledge. To circumvent these problems, microsatellite markers, which are currently identified as the most widely used marker system for plant variety characterization, are selected to analysis the uniformity, genetic diversity, genetic relationship of major rice varieties in China, and a microsatellite-based database of these varieties has been constructed. The primary results were summarized as following:1. A set of five well-chosen microsatellite markers were presented to detect clear and effectively within-cultivar variation in rice. 18 (43.90%) of 41 rice varieties with 2-7 sources show within-cultivar heterogeneity among different sources with the same name, therefore it should be noted that the sources of the materials were selected carefully as used in constructing a microsatellite database. To assess accurately intra-cultivar uniformity of the major rice varieties in China at 5 microsatellite loci, 11 typical varieties were selected and analyzed with larger samples containing 50 individuals per variety. The degrees of non-uniformity of selected varieties varied from 0-10.0%, with the percentage of heterogeneity ranged from 0.36 to 5.45%, and an overall average of 1.67% at 5 SSR loci. The results show that 6 of 11 typical rice varieties in China are completely uniform, and the degrees of non-uniformity within varieties across all loci are in general lower than 5%.2. A set of 24 SSR primer pairs located on 12 chromosomes in rice were used to construct a microsatellite database, evaluate the genetic diversity and analysis the genetic relationship of sixty-three major conventional varieties and parental lines of major hybrid combinations, which were widely used in the commercial rice production in China. A total of 135 alleles were detected, and the number of alleles per marker ranged from 2 to 9, with an average of 5.6. FP (Frequency of polymorphism) values ranged from 0.486-0.840, with an average of 0.682. All the varieties can be clearly discriminated from each other based on the information obtained from the 24 markers. Cluster analysis of the 63 cultivars based on the genetic similarity showed three major groups and eight subgroups. Group III corresponded to the japonica subspecies, whereas group I and II belonged to the indica subspecies. The result from cluster analysis still showed a significant feature of geographical distribution. The indica varieties (group I) were divided into two subgroups (G I -1 and G I -2), which separately distributed in South China and the Changjiang River area. The japonica varieties(group III) were divided into two subgroups (GIII-1 and GIII-2) , which separately distributed in North China and Jiangsu, Zhejiang provinces. The average genetic similarity of indica materials (0.388) was significantly lower than that of japonica materials (0.638), which showed that indica materials had a higher level of genetic diversity. Both Male sterile lines and restorer lines of hybridcombinations showed vulnerable genetic background. Compared to male sterile lines, restorer lines showed higher level of genetic variation. The results indicated that the genetic relationship constructed by SSR markers was identical with pedigree analysis.更多还原