【作者】 叶俊；

【导师】 石春海；

【作者基本信息】 浙江大学 ， 作物遗传育种， 2006， 硕士

【摘要】 水稻是禾本科作物研究的模式植物。随着水稻全基因组序列的测定完成,对基因功能的研究已成为重点,研究基因功能最直接和有效的方法是构建水稻突变体库。理化诱变具有技术条件简单,突变频率高,能够在短时间内构建具有大量突变体的突变群体,是水稻突变体库构建的重要方法之一。本研究旨在选用已完成全基因组序列测定的籼稻品种“9311”为研究对象,利用物理诱变(γ射线)和化学诱变(EMS溶液)的方法处理籼稻品种“9311”种子,筛选植株形态性状(包括根系性状)突变体和稻米品质性状突变体,构建出变异类型丰富的水稻突变群体,为水稻功能基因组学研究和水稻遗传改良提供良好的基础材料。 在植株性状上,通过物理诱变和化学诱变处理,获得了606份叶片、茎秆、穗部、生理等性状变异范围较大的突变体群体,其中γ射线诱变处理417份、EMS诱变处理189份,形态突变频率分别为5.94%和3.78%。与EMS诱变群体相比,γ射线诱变群体的变异范围更广、突变频率也更高,大部分在EMS诱变群体中得到的突变类型,在γ射线诱变群体中都能出现,但紫色叶鞘突变,叶片类病斑突变等极少数突变类型只出现在EMS诱变群体中。 利用新建立的根系突变体的筛选方法,在两种诱变群体中共筛选到69份短根、无侧根、种子根变长、根向重力性异常等突变体,其中γ射线和EMS诱变处理中分别发现48份和21份突变体,突变频率分别为0.68%和0.42%,突变频率低于植株地上部的形态性状变异。短根的突变频率较其它根系突变性状要高,无侧根或短侧根突变株均表现为种子根与不定根较短,但短根突变体并不一定表现为无侧根或短侧根。 在稻米品质突变体的筛选中,γ射线诱变群体中共获得稻米品质性状突变体60份,突变频率为0.85%。其中糙米颜色突变体1份、稻米垩白突变体14份、米粒形状突变体3份、稻米直链淀粉含量突变体14份、稻米碱消值突变体6份、稻米蛋白质含量突变体7份、稻米苏氨酸含量突变体1份,稻米赖氨酸含量突变体6份,稻米苯丙氨酸含量突变体8份。新构建的水稻“9311”植株形态性状突变体群体和稻米品质性状突变群体可以为今后深入研究水稻基因组功能、演化及基因组间的相互关系提供材料基础。更多还原

【Abstract】 Rice (Oryza sativa L.) has become a model plant for the study of the cereal genomes in the last decade. Recent completion of the draft sequence for the rice genome has resulted in an explosion of information on rice genes. The challenge for the post-sequencing era is to identify the biological functions for these genes. Of all the approaches used for discovering the gene function, the more useful one is based on a saturated mutagenesis population, which is a straight and efficient way to understand the role of all the genes. In all the methods for constructing the mutant liberary, the physical and chemical mutangenesis might be the main methods, which were simple and effective. They can be used to produce a large number of mutants with high mutagenesis frequence in a short period and to establish a mutant population. The purpose of the present experiment is to screen different plant morphogenesis mutants and rice quality mutants by treating the seeds of the indica rice variety 9311 with y-rays or EMS (Ethyl Methan Sulfonate), of which has been completely sequenced in the whole genome. The mutant library created will be helpful for gene identity and gene functional analysis.For plant traits, some mutants with the variations of leaf, stalk, panicle or root traits were found in the progenies. The total mutants frequence were 5.94% and 3.78%for y-rays and EMS, respectively. Four hundred and seventeen out of the 606 mutants were found in y-rays mutagenesis population, and 189 ones in EMS mutagenesis population. Comparing with EMS mutagenesis, more mutants were screened in y-rays mutagenesis population. Most of the mutants by EMS could be found in y-rays mutangenesis population, but some mutants, such as the purple leaf sheath mutant and lesion resembling disease mutant, were only found in EMS mutagenesis population.The root trait mutants were screened in the two mutangenesis population and some mutants with the variations of short roots, no lateral root, long seminal root or gravity insensitive of root were found in progenies. The root traits mutants frequence were 0.68 % and 0.42% for y-rays and EMS, respectively, and it was lower than the mutagensis frequence for plant traits. Forty-eight out of the 69 mutants were induced by y-rays and 21 ones were induced by EMS. The frequence of short root mutants was higher than that for other root mutants. The mutants without lateral root mutants or short lateral roots mutants had the short seminal root and crown roots simultanously. There was no short lateral root or lateral root for some of the short roots mutants.For the rice quality mutants, 60 mutants were found in y-rays mutagenesis population and the mutant frequence was 0.85%. Among them, there were 1 brown rice color mutant, 14 rice chalkiness mutants, 3 rice shape mutants, 6 rice alkali spreading value mutants, 7 protein content mutants, 14 amylose content mutants, 1 threonine content mutants, 6 lysine content mutant and 8 phenylalanine mutant. The mutant library created for indica rice variety 9311, which include different plant morphogenesis mutants and rice quality mutants, will be helpful for the research in rice founctional genomics and the relationship among the cereal genome.更多还原