【作者】 杨敏娜；

【导师】 井金学；

【作者基本信息】 西北农林科技大学 ， 植物病理学， 2008， 博士

【摘要】 小麦条锈病是由条锈菌(Puccinia striiformis f.sp.tritici)引起的世界性小麦病害,在我国曾多次大流行,给小麦生产造成重大损失。目前,虽然我国小麦抗病品种数量众多,但其抗源的单一化、同质化严重,从而导致病害频繁流行。所以,许多小麦条锈病工作者提出了明确现有品种(系)抗病特点和抗病基因分布、挖掘新的抗源和抗条锈病基因、增加小麦抗源多样性、发掘高品位抗病基因等策略,以稳定小麦病害系统。因此许多研究者已把注意力集中到深入研究利用外源基因和重要小麦抗病基因上,试图解决小麦品种抗病性丧失难题。研究含有外源抗病基因种质资源的重要抗病品种的抗条锈性遗传机制和抗病基因,将增加小麦抗条锈病基因的多样性,为小麦抗病性遗传改造提供丰富的物质贮备,对控制小麦条锈病危害具有重要意义。本研究对生产上已推广和即将推广使用的具有外源抗病基因的5个品种(系)和已知抗条锈基因载体品种进行了遗传分析和分子作图,取得以下结果:1.经典遗传学分析表明,中梁88375对CYR31的抗病性由一对显性核基因控制,把该基因暂命名为Yr88375。BSA结合分子标记的方法,一方面建立了与Yr88375连锁的6个微卫星标记Xgwm335、Xwmc289、Xwmc810、Xgdm116、Xbarc59与Xwmc783,并将Yr88375定位于小麦5BL,距离Yr88375最近的两个微卫星位点是Xgdm116、Xwmc810,遗传距离分别是3.1 cM和3.9 cM,最远的标记Xwmc783与Yr88375之间的遗传距离为13.5 cM。另一方面利用RGA标记法结合缺四体定位法,将Yr88375定位于小麦5B染色体,并找到了两个与之连锁的RGA标记Yr88375-RG1和Yr88375-RG2,与Yr88375的遗传距离分别为3.6 cM和4.2 cM。系谱分析结合分子标记结果表明,Yr88375很有可能是一个来自于中间偃麦草(E.intermedium),并与已知抗条锈病基因不同的新基因。2.中梁22号与铭贤169杂交F2代群体苗期抗条锈病遗传分析结果表明,中梁22号含有3-5对抗条锈基因。中梁22号对CYR31的抗病性由一对显性核基因(暂命名YrZhong22)和一对隐性胞质基因共同控制,用SSR标记结合集群分离分析法(BSA),建立了与YrZhong22连锁的4个微卫星标记,分别是Xwmc289、Xwmc810、Xgdm116和Xbarc232,并将YrZhong22定位于小麦5BL染色体。YrZhong22与相邻微卫星位点Xwmc810和Xgdm116的遗传距离分别是2.7 cM和4.4 cM。系谱分析及分子标记分析表明,YrZhong22可能是一个来自中间偃麦草的新抗条锈病基因。3.采用生理小种CYR30、CYR31、SU11-4、SU11-11对易位系M8657-1进行遗传分析发现,对CYR30的抗病性由一对隐性核基因控制;对CYR31的抗病性由两对显性核基因(互补作用)控制;对SU11-4的抗病性由一对显性基因控制;对SU11-11的抗病性由一对隐性核基因控制。利用BSA法对SSR引物进行筛选,获得了3个与易位系M8657-1主效抗条锈病基因YrElm1连锁的多态性SSR标记,它们分别是Xgwm636、Xwmc522和Xwmc453,与目的基因的遗传距离依次为8.9 cM、5.9 cM和10.3 cM。根据这些扩增位点的染色体位置,可推出YrElm1位于小麦2AS染色体上,而目前定位于2AS染色体上的抗条锈基因只有Yr17,通过对抗病基因来源以及基因的抗病性综合分析可知,YrElm1和Yr17是完全不同的,因此,YrElm1可能是一个位于小麦2AS染色体上的新的抗条锈病基因。4.采用生理小种CYR29、CYR31、SU11-4、SU11-11对易位系M853-2进行遗传分析,结果表明,对CYR29的抗病性由两显一隐的三对核基因共同控制;针对CYR31的抗病性由两对显性核基因(互补作用)控制;对SU11-4的抗病性由两对显性基因(互补作用)和一显一隐的(呈独立或重叠遗传)胞质基因共同控制;对SU11-4的抗病性由一对显性核基因控制。BSA法结合SSR标记分析,筛选到1个位于4BL上的SSR标记Xgwm495,连锁分析表明,YrElm2与Xgwm495的遗传距离为7.6 cM,YrElm2位于小麦4BL染色体上。通过与已定位在4BL染色体上其它基因的比较可知,YrElm2是一个来自于柔软滨麦草、不同于已知基因的抗条锈病基因。5.对易位系M853-4接种生理小种CYR29、CYR30、CYR31、SU11-11进行遗传分析,结果表明,M853-4对CYR29、CYR30、CYR31的抗病性均由一对显性核基因控制;对SU11-11的抗病性由一显一隐的两对核基因(呈独立或重叠遗传)共同控制。利用微卫星标记的方法筛选到3个与M853-4主效抗条锈病基因YrElm4连锁的多态性SSR标记,它们分别是Xwmc654、Xgwm304和Xgwm129,与目的基因的遗传距离依次为5.8 cM、7.1 cM和10.3 cM。根据小麦微卫星遗传图谱可知,这些扩增位点位于小麦5AS上,因此YrElm4位于小麦5AS染色体上。6.对条锈病已知基因载体品种Gaby的抗锈遗传规律进行了系统分析,用CYR29、CYR32和SU11-11对该品种进行了抗条锈性遗传分析。研究结果表明,Gaby对CYR29的抗锈性表现为一对显性抗病基因控制(暂命名为YrGaby);对CYR32,其为母本时抗病性由两对基因控制(可能是两对隐性基因,也可能是存在累加作用的两对显性基因),为父本时抗病基因由一对显性基因和两对隐性抗病基因控制;对SU11-11,其为母本时抗病性由三对显性基因控制(其中两对表现为累加作用),为父本时抗病性由一对完全显性抗病基因和一对隐性基因控制。为确定YrGaby染色体位置,利用BSA法从320对SSR引物中进行筛选,获得4个位于小麦4AL染色体的SSR标记位点,这些标记分别是Xgwm397、Xwmc161、Xwmc698和Xwmc760,与目的基因的遗传距离依次为13.8 cM、8.6 cM、5.1 cM和16.6 cM。另一方面,利用RGA标记法结合一整套缺四体定位法,将YrGaby定位于小麦4A染色体,并找到了2个与之连锁的RGA标记YrGaby-RG1和YrGaby-RG2,二者与YrGaby的遗传距离分别为4.2 cM和9.1 cM。与抗病基因YrGaby连锁的分子标记的获得,为该品种的合理利用、抗病基因合理布局以及分子标记辅助育种提供了可靠的依据。更多还原

【Abstract】 Stripe rust, caused by Puccinia striiformis f.sp. tritici, is one of the most serious diseases of wheat in the worldwide. China is the largest epidemic region in the world and severe losses in grain yield have been reported. At present, the simplicity and homology of stripe rust resistance background in commercial wheat cultivars have not changed all though a lot of cultivars are used in wheat production. Identification and excavation new stripe rust resistance genes is an important method for controlling stripe rust. Geneticists and plant breeders pay more attention to wild relatives and elite cultivars carring durable resistance in order to search new resistant germplasms.The genitic mechanism of 5 variaties derived from alien resistant resources and Gaby to stripe rust were studied in this research,The results are as follow:1. Genetic analysis of Zhongliang 88375 indicated that resistance to race CYR31 was controlled by a single dominant gene, temporarily designated as Yr88375. To molecular map Yr88375, a F2 segregating population consisted of 163 individuals was constructed on the basis of the hybridization between Zhongliang 88375 and a susceptible wheat line Mingxian169.On the one hand, six SSR markers,Xgwm335, Xwmc289, Xwmc810, Xgdm116, Xbarc59 and Xwmc783 linked to Yr88375 , as they were all located on chromosome 5BL , Yr88375 was also located on that chromosome arm, closely linked to Xgdm116 and Xwmc810 with genetic distances of 3.1 and 3.9 cM, respectively. The furthest marker Xwmc783 was 13.5 cM toYr88375. On the other hand, the resistance gene Yr88375 was located on chromosome 5B by RGA tagging and the 21 Chinses Spring nulli-tetrasomic. Hence, pedigree analysis of Zhongliang 88375 combined with SSR markers support on the conclusion that the highly resistance gene Yr88375 derived from Elytrigia intermedium, is a novel gene for resistance to stripe rust in wheat.2. To identify and tag new resistance genes to stripe rust in a wheat cultivar Zhongliang 22, Genetic analysis indicated that Zhongliang 22 contains three to five resistance genes and one dominant nucleic gene (temporarily designated as Yrzhong22) and one recessive CYR31 toplasmic gene conditioned stripe rust rust resistance in Zhongliang 22 inoculated with CYR31.Using SSR markers combined with bulked segregation analysis (BSA) revealed that four SSR markers located on chromosome 5BL were linked to Yrzhong22. The genetic distances between Yrzhong22 and its nearest markers Xwmc810 and Xgdm116 were 2.7 cM and 4.4 cM, respectively. Yrzhong22 is probably a novel resistance gene to wheat stripe rust donated from Elytrigia intermedium on the basis of pedigree analysis and molecular result.3. Genetic analysis of translocation line M8657-1 indicated that resistance gene conferring to CYR30 was controlled by one recessive gene, resistance genes conferring to CYR31 controlled by two dominant karyoplasms genes (complementary); resistance gene conferring to SU11-4 was controlled by one dominant gene temporarily designated as YrElm1,resistance gene conferring to SU11-11 was controlled by one single recessive karyoplasms gene. Through SSR and analysis with resistance pool and susceptible pool, Three SSR markers on the short arm of chromosome 2A were found linked to YrElm1. The SSR markers were Xgwm636、Xwmc522 and Xwmc453 and their genetic distances from YrElm1 were 8.9 cM、5.9 cM and 10.3 cM, respectively. At present, stripe rust resistance gene Yr17 have been located to chromosome 2AS.Based on the origin of resistance genes and seedling test pattern, The result showed that YrElm1 is probably a new stripe rust resistance gene.4. Inheritance of translocation line M853-2 by artificial inoculation with different races at seedlings. The results showed resistance gene conferring to race CYR29 was controlled by two dominant and one recessive genes independently, the resistance to race CYR30 was controlled by two dominant and one recessive genes (they are karyplasms genes) and three recessive cytoplasmic genes, and the resistance gene to CYR31 was controlled by two dominant complement genes, and the resistance to SU11-4 was controlled by one dominant and one recessive karyplasms gene and two dominant cytoplasmic genes ,while the resistance to the race SU11-11 was controlled by one dominant gene, temporarily designated as YrElm2. To develop molecular markers for YrElm2, bulk segregation analysis combined with 320 SSR markers were used for, one SSR marker, Xgwm495 on the 4BL was associated with YrElm2. The genetic distance between Xgwm495 and YrElm2 was about 7.6cM. YrElm2 was located on the 4BL. By comparision with other genes on 4B chromosome, we could conclude that YrElm2 is probably a novel gene origin from Elymus mo11is (Trin.) Hara.5. Genetic analysis of translocation line M853-4 indicated that resistance gene conferring to races CYR29,CYR30,CYR31 were all controlled by a single dominant karyoplasms gene; Resistance of M853-4 conferring to SU11-11 was controlled by one dominant and one recessive genes. A total of 320 SSR primers were used to test the parents as well as resistant and susceptible bulks. Three SSR markers on the short arm of chromosome 5A were found linked to YrElm4. The SSR markers were Xwmc654、Xgwm304 and Xgwm129,and their genetic distances from YrElm4 were 5.8 cM、7.1 cM and 10.3 cM,respectively.6. It had proved that wheat cultivar Gaby is an important resistant resource to stripe rust. Genetic analysis of Gaby indicated that resistance gene conferring to CYR29 was controlled by one dominant gene temporarily designated as YrGaby. To CYR32, Gaby has two genes resisted(they possibly are either recessive or present addition effect) when it is female parent ,and it possibly has one dominant and two recessive genes when it is male parent. To SU11-11 strain, Gaby has three genes (two of them present additive effect) when it is female parent, and has one dominant and one recessive genes when it is male parent .Bulk segregation analysis combined with 320 SSR markers were used for, Four SSR markers on the long arm of chromeosome4A were found linked to YrGaby ,they were Xgwm397、Xwmc161、Xwmc698and Xwmc760,and their genetic distances from YrGaby were 13.8 cM、8.6 cM、5.1 cM and 16.6 cM,respectively. In addition, the resistance gene YrGaby was located on chromosome 4A by RGA tagging and the 21 Chinses Spring nulli-tetrasomic, and two RGA markers were linked to YrGaby with genetic distance was 4.2 cM and 9.1 cM, repectively.更多还原