一个水稻颖花突变体的遗传分析和基因定位

发布时间：2018-08-21 13:50

【摘要】：水稻颖花发育过程对其产量和品质的形成起重要的直接影响作用,因此对水稻颖花发育遗传机理的研究具有重要的意义。通过60Coγ射线辐射诱变9311获得了一个内稃及其雌雄蕊异常的突变体apps(abnormal palea and pistil-stamen)。本实验研究了 apps 突变体花器官的形态特征、主要农艺性状及其遗传,对突变体apps基因进行了定位及候选基因的预测。主要研究结果如下:1、apps突变体部分颖花发育出现异常,其表现为外稃发育都正常,内稃小而皱缩,雌雄蕊数目出现不同程度地变化,颖花中的部分雄蕊雌蕊化,甚至一些颖花雄蕊全部雌蕊化。另外,穗基部及每个枝梗基部的颖花表型为正常。与野生型品种9311相比,突变体的株高变矮、包穗、穗子变短;谷粒变短、千粒重和结实率降低。2、遗传分析表明,该突变体apps的内稃和雌雄蕊异常性状是受一对隐性基因控制的。3、将培矮64s与颖花突变体apps杂交的F2代中所有突变单株作为定位群体,利用SSR分子标记技术,对apps进行定位。将apps基因初步定位在1号染色体短臂上RM243和RM490之间,与两标记间的遗传距离均为6.875 cM。最终将apps基因精细定位在MM1445和MM1450标记之间,它们之间的物理距离约15.3kb。4、利用RGAP数据库分析,发现目标区间内有2个预测基因。根据功能分析推定LOC_Os01g12890为可能的目标基因,对其进行测序与正常亲本序列比对分析。发现apps中的LOC_Os01g12890基因的第4个外显子中有两个碱基发生变化,其中第1367位碱基由G突变为T,第1368位碱基A缺失,从而导致该基因翻译提前终止,据此确定LOC_Os01g12890为候选基因。
[Abstract]:The development of spikelet plays an important and direct role in the formation of grain yield and quality, so it is of great significance to study the genetic mechanism of spikelet development in rice. A mutant apps (abnormal palea and pistil-stamen with abnormal Palea and its pistil was obtained by 60Co 纬 -ray radiation mutation 9311. The morphological characteristics, main agronomic characters and inheritance of floral organs of apps mutants were studied. The apps gene location and candidate genes were predicted. The main results were as follows: some spikelets of the 1: 1 apps mutant showed abnormal development, which showed that the Lemma developed normally, the Palea was small and shrinked, the number of pistil and stamen changed in varying degrees, and some of the stamens in the spikelet were pistilate. Even some spikelets are completely pistilate. In addition, the spikelet phenotype at the base of the ear and at the base of each branch was normal. Compared with wild-type variety 9311, the plant height, panicle, spike, grain weight and seed setting rate of the mutant became shorter, 1000-grain weight and seed setting rate decreased .2.The genetic analysis showed that, The abnormal characters of Palea and pistil of the mutant apps were controlled by a pair of recessive genes. All the mutant plants in F2 generation of Pei'ai 64s crossing with spikelet mutant apps were used as the locational population. SSR molecular marker technique was used to localize apps. The apps gene was preliminarily mapped between RM243 and RM490 on the short arm of chromosome 1. The genetic distance between the two markers was 6.875 cm. Finally, the apps gene was carefully mapped between MM1445 and MM1450 markers, and the physical distance between them was about 15.3kb.4. two predictive genes were found in the target region by RGAP database analysis. According to functional analysis, LOC_Os01g12890 was presumed to be a possible target gene, which was sequenced and analyzed with normal parent sequence alignment. It was found that there were two bases in the fourth exon of the LOC_Os01g12890 gene in apps, in which the 1367 base was mutated from G to T and the 1368 base A was deleted, which led to the early termination of the translation of the gene. LOC_Os01g12890 was identified as a candidate gene.
【学位授予单位】：福建农林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S511

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