【作者】 邱生平；

【导师】 张红生；

【作者基本信息】 南京农业大学 ， 作物遗传育种， 2005， 博士

【摘要】 盐胁迫损害植物质膜的正常功能，造成植物气孔关闭，光合降低，能耗增加，养分离子吸收不平衡。植物耐盐机理主要有渗透调节、拒盐机理、盐的区隔化、钾离子运输调控系统、水通道蛋白和光合途径改变等几种假说，其耐盐性遗传是受主基因+多基因混合遗传模型的控制，目前已从许多植物中分离了一些盐胁迫诱导的基因及基因上游序列，有些耐盐基因已被成功转入植物中，提高了植物的耐盐性。 水稻是中度盐敏感作物，要提高水稻在盐渍土上的生产力，培育耐盐性水稻品种是一项经济而有效的措施。本研究以太湖流域地方品种韭菜青（P₁）和菲律宾国际水稻研究所育成的籼稻品种IR26（P₂）的重组自交系（RILs）群体的248个家系为材料，进行水稻耐盐性的遗传研究及耐盐相关基因的克隆。结果如下： 1。水稻苗期耐盐性的遗传分析 在0.5％和0.7％的NaGl胁迫下，对水稻苗期盐害级别、相对株高、相对茎叶干重、相对根干重和根系Na⁺／K⁺等5个耐盐相关性状进行遗传分析。结果表明：在二种浓度NaCl胁迫下，两亲本的耐盐能力存在显著差异，韭菜青的耐盐能力显著高于IR26。遗传分析表明，在0.5％和0.7％NaCl胁迫下盐害级别的遗传符合两对抑制作用主基因模型（B-1-9）、相对苗高符合两对互补作用主基因+多基因混合遗传模型（E-1-7）、相对茎叶干重和相对根干重符合两对连锁累加作用主基因+多基因混合遗传模型（E-2-6）、根系Na⁺／K⁺符合三对加性-上位性作用主基因+多基因混合遗传模型（G-1）。在0.5％的NaGl胁迫下，控制盐害级别、相对苗高、相对茎叶干重、相对根干重和根系Na⁺／K⁺5个性状的主基因+多基因共同解释的遗传率分别为32.7％、55.8％、90.2％、87.5％、79.1％。在0.7％的NaCl胁迫下，这些性状的主基因+多基因共同解释的遗传率分别为42.3％、60.8％、61.9％、65.8％、79.0％。 2．耐盐性QTLs的检测 在构建了一个由94个SSR标记组成的分子遗传图谱基础上，对盐害级别，相对苗高，相对茎叶干重，相对根干重和根系Na⁺／K⁺等5个水稻苗期耐盐相关性状的QTL进行定位。结果显示，在0.5％和0.7％的NaCl胁迫下，5个耐盐相关性状共检测到22更多还原

【Abstract】 Salt stress damages the functions of plasma membrane and induces stoma-closing, photosynthesis-decreasing, over energy-consuming and unbalance of inorganic ion absorbing in plants. Plant salt tolerance was genetically controlled by mixed inheritance mode with major plus polygenes. Many salt-inducible genes have been cloned, and there are some hypotheses on molecular mechanisms of salt-stress tolerance, such as osmotic adjustment, salt-resistence, compartmentation, regulated potassium transport system, regulated water channel and converted photosynthesis pathway. Some salt-inducible genes have been transformed into plants, and it was evidenced that exogenous gene can enforce the ability to tolerate salt stress.Rice is grown widely in the world with moderate sensitivity to salinity. The most effective approach to improve rice salt tolerance is breeding salt tolerance varieties. In order to breed salt tolerance cultivars genetic analysis and relative gene cloning for salt tolerance in rice must be studied. A recombinant inbred lines(RILs) population of 248 lines derived from a cross of Jiucaiqing(japonica)/IR26(indica) by the single seed descent method was used to conduct genetic analysis and relative gene cloning for salt tolerance in rice. The main results are followings:1. Genetic analysis for salt tolerance in rice seedlingsThe salinity tolerance rating, relative plant height, relative dry weight of shoot, relative dry weight of root and Na~+/K~+ of root were evaluated under 0.5% and 0.7% NaCl stress, then genetic analysis of these traits were identified. Jiucaiqing and IR26 with various salt tolerance were identified under two NaCl concentrations, the salt tolerance of Jiucaiqing is better than IR26. The genetic analysis results showed that salinity tolerance rating, relative plant height, relative dry weight of shoot and relative dry weight of root, Na~+/K~+ of root were genetically controlled by genetic mode of two inhibiting effect major genes(B-l-9), two complementary effect major genes plus polygenes (E-1-7) , two linkage additive effect major genes plus polygenes (E-2-6) , three additive epistasis major genes plus更多还原