【作者】 许延波；

【导师】 吴建宇；

【作者基本信息】 河南农业大学 ， 作物遗传育种， 2005， 硕士

【摘要】 玉米是我国主要的粮食作物、饲料作物和重要的工业原料,常年播种面积在2,500万公顷,上升为我国第二大粮食作物。我国主要有30多种病害严重影响了玉米产量和品质,选育抗病近等基因系和高抗自交系是深入进行遗传规律研究和抗病育种的基础,而利用常规育种方法具有周期长、效率低并需要接种等环节。本文利用分子标记辅助选抒结合常规育种的方法进行了抗玉米矮花叶病近等基因系以及玉米矮花叶病和玉米青枯病的抗病基因聚合自交系的选育研究。主要结论如下: 一、采用常规的回交育种与分子标记辅助选择相结合,以Mo17为轮回亲本,四一为供体通过一次杂交,四次回交和一次自交的育种程序,进行抗玉米矮花叶病近等基因系的选育。利用田间接种鉴定和与抗病基因紧密连锁的SSR分子标记对单株前景进行选择。利用表型综合农艺性状和均匀分布在玉米全基因组的SSR分子标记对单株的遗传背景进行选择,其中前两代主要进行前景选择和利用表型综合农艺性状进行遗传背景的选择,BC3F1代首先进行前景选择和综合农艺性状的选择,再利用SSR分子标记对选择到的单株进行背景选择。BC4F1和BC4F2代主要通过分子标记辅助进行前景和背景选择,通过三年五代的选择,到2005年获得了只含有四一第三染色体抗病基因、第六染色体抗病基因以及同时含有两个抗病基因的近等基因系。 二、根据BC3F1代背景选择的标记位点信息,对各单株SSR标记位点进行监控,每个单株或其后代只保留单个SSR标记位点,或连锁的几个SSR标记位点,剔除遗传背景中其他标记位点。获得了一系列以SSR分子标记为基础的四一其他染色体片断近等基因系。 三、利用四一×Mo17的BC3F1田间抗感分离比例,以及单株抗病基因的分子检测进一步验证了两个显性互补抗病基因的遗传模式。 四、获得了玉米矮花叶病抗病基因Mdml紧密连锁的SSR分子标记bnlg1600,其与抗病基因间的距离为3.2 cM。然后利用bnlg1600对Mdml进行选择,利用phi077对mdm(t)进行选择,采用二环系法进行抗病基因的聚合,最终获得了5个株系,通过接种矮花叶病病毒发现,这5个株系对矮花叶病的抗性优于其亲本。 五、利用四一和1145间有多态性的分子标记对四一中两个玉米矮花叶病抗病基因和1145中的一个抗青枯病基因进行选择,并结合常规育种的方法到目前共获得了15个聚合株系,初步进行了接种鉴定和病圃鉴定其抗性。同时组配了150个组合,2005年将进行配合力分析。更多还原

【Abstract】 Maize sown in 25 million hectares is second to rice as the most important crops in China. The losses in maize production and poor quality grain have been influenced by more than 30 kinds of more common maize diseases. It is necessary to develop near isogenic lines and inbred lines with the resistance genes used in the research on inheritance of resistance and resistant breeding by marker assistant selection with conventional breeding instead of conventional breeding. The conclusion was as follows:Firstly, the breeding program of marker assistant selection with conventional breeding was done. The Susceptible inbred line Mo17 was used as recurrent parent, and the resistant inbred line Siyi as nonrecurrent parent. 4 flanking markers were used for selecting for the two resistance genes and 129 SSR markers that were polymorphism between Siyi and Mo17 with phenotypic selection were used for selecting for the genetic background of Mo17. Crossing once, backcrossing four times, selfing once, then got the NILs with the gene on chr.3, the one on chr.6 and these two genes in 2005, while 22 NILs with one and a few markers were obtained. Two complementary dominant genes conditioning the resistance, with a new genetic model, of the elite maize inbred line Siyi were confirmed by the genetic analysis based on BC3F1 from the combination of Siyi and Mol7.Secondly, the resistance gene to maize dwarf mosaic Mdm1 in the inbred line Pa405 was tagging by microsatellite markers, the linkage distance between the marker bnlg1600 and the gene is 3.2 cM. The two resistance genes to maize dwarf mosaic, Mdml and the gene mdm (t) in the lines Huangzaosi, were pyramided by MAS with Pedigree method. 5 inbred lines with high resistance to MDMV developed.Thirdly, the two resistance genes to MDMV in the inbred line Siyi and the resistance gene to Stalk Rot (pythium inflatum) Rpil in the line 1145 were pyramided. 15 inbred lines with high resistance to MDMV and stalk rot developed.更多还原