【作者】 隋炯明；

【导师】 顾铭洪； 李欣；

【作者基本信息】 扬州大学 ， 作物遗传育种， 2006， 博士

【摘要】 到目前为止,在水稻上已经鉴定了70多个矮秆基因,但它们大都具有不良效应,从而制约了它们在生产上的利用。在水稻矮化育种中所利用的矮秆材料主要受一个相同或等位隐性矮秆主基因控制。同一矮秆基因的利用潜伏着由遗传单一而带来的风险,因此发掘、鉴定和利用新的矮秆资源已日益为水稻育种界所重视。本研究从一个籼稻标记基因系材料多蘖矮中分离、鉴定出一个新的水稻半矮秆基因sdt3。进一步通过杂交分离,获得了仅由新的矮秆基因控制的矮秆系,并明确了该基因在染色体上的位置。在前人的研究基础上,对另一个籼稻突变体新桂矮双矮中的半矮秆基因sdg进行了精细定位,将它限制在一个很小的物理距离内,然后对它进行了克隆和互补实验,主要研究结果如下:1、籼稻标记基因系材料多蘖矮的矮生性状由2对隐性半矮秆基因控制,分别为sd1和一个新的半矮秆基因,该基因初步定名为sdt3。以多蘖矮与南京6号杂交F2的分离群体为基础,应用SSR标记进行连锁分析,将半矮秆基因sdt3定位于第11染色体的微卫星标记SSR98和SSR35之间,分别相距0.06cM、0.13cM,这两个标记分别位于BAC克隆AC137588的91kb和AC104847的60kb处,这两个BAC的全序列测定已完成,分别为154kb和156kb,且相互重叠30kb,因此可推断出SSR98和SSR35的物理距离在93kb左右,sdt3基因就位于这个区段上。以南京6号为轮回亲本与多蘖矮进行回交和自交获得由半矮秆基因sdt3控制的近等基因系(新多蘖矮),以赤霉素处理表明由sdt3控制的半矮秆系新多蘖矮对赤霉素不敏感。2、sdg矮秆系对外源GA不敏感,它在幼苗期降低了对外源赤霉素的敏感性。在GA处理前后,我们分别用扫描电镜和光学显微镜观察了野生型品种南京6号更多还原

【Abstract】 (Yangzhou University, Yangzhou, Jiangsu Province, P.R. China, 225009) At present, more than 70 semidwarf or dwarf genes have been identified, but most of these semidwarf or dwarf genes have impractical pleiotropic phenotypes and exert unfavorable effects on many agronomic characters therefore restricting their use in cross breeding. Conventional genetic analysis reveales that all of the semidwarf genes in cultivars are controlled by an allele at the sd1 locus. The frequent use of the single semidwarf gene might cause genetic vulnerability to pests and diseases. Therefore, it is essential to develop an alternative or new source of semidwarf genes to broaden the genetic basis of the semidwarfism.. In this study, we described the identification, characterization, fine mapping of onenew rice semidwarf gene sdt3 and fine mapping, cloning and functional analysis of the other semidwarf gene sdg, The main results were as follows:1.A marker line material Duonieai(DA)used in the study was a dwarf mutant , however genetic analysis showed that its dwarf trait was controlled by two recessive semidwarf genes, sd1 and a new semidwarf gene sdt3.A F2 segregating population更多还原