【作者】 蒲宗君；

【导师】 郑有良；

【作者基本信息】 四川农业大学 ， 作物遗传育种， 2008， 博士

【摘要】 由条锈菌（Puccinia striiformis West.f.sp.Tritici）引起的小麦条锈病是世界性小麦病害。条锈病是我国小麦生产中最严重、最广泛的病害,每年均会发生大面积的危害。从目前小麦生产和育种的情况来看,虽然抗病品种或抗性材料数量多,但抗性基因单一化并未根本改变。因此,了解现有品种（系）和育种材料的抗性状况和基因分布,挖掘新的抗病基因具有重要的意义。本研究从抗性评价、抗性基因遗传分析及其分子标记等三个方面对小麦抗条锈病基因资源进行研究。主要结果如下:1.鉴定、筛选了一批小麦抗条锈病资源。利用条锈菌优势小种CYR31、CYR32和混合小种对从国内外征集的106份普通小麦品系进行了苗期抗性鉴定。结果表明,NIL-2和NIL-7等20份品系对3类生理小种均表现高度抗病;Houtman和17IBWS17等26份品系表现中度抗病;17IBWSN53和17IBWSN31等33份表现中度感病;Lowan和Wilgoyre等27份表现高度感病。所鉴定出的抗源大多数来自国外,这为四川小麦抗条锈病育种奠定了较为丰富的基因资源。从本研究中同时还发现,3类小种的毒性大小表现为:混合小种＞CYR32＞CYR31。2.首次在四川盆地对小麦慢条锈性进行了初步研究。利用条锈菌混合小种对51份小麦品系在四川盆地的慢条锈性进行了评价。通过不同生育阶段的抗病性表现,将参试品系划分为5种类型:G1-高度抗锈类型（严重度10%以下）,G2、G3属慢锈类型（严重度10-40%）,G4-高度感锈类型（严重度50%以上）和G5-高温抗病类型。在分期播种条件下,对条锈菌侵染敏感程度表现为:G1和G4类型的抗感表现与播期无关,而G2和G3类型中的部分品系和G5类型的抗感反应与播期密切相关。初步筛选出ICARDA-53和0R7207等14份品系具有慢条锈性:Giles和Kauzs等6份品系具高温抗条锈性。最终严重度可用于慢条锈性鉴定及育种参考的简单指标。3.分析了2份来自叙利亚和2份来自CIMMYT小麦材料对条锈病的抗性遗传。利用条锈菌优势小种CYR3l和CYR32对源于叙利亚小麦ICA31和ICA70分别与川麦28杂交的F₁、F₂和BC₁群体进行抗性遗传分析。结果表明,ICA31对CYR31和CYR32小种的抗条锈性均表现为由1对显性纯合基因控制;ICA70对CYR31小种的抗条锈性表现为由1对显性基因和1对隐性基因互补作用控制,而对CYR32小种的抗条锈性表现为由1对隐性基因控制;用CYR32小种对来自CIMMYT的两份小麦CI-66和CI-9与川麦28杂交后代的F₁、F₂和BC₁群体进行遗传分析,CI-66的抗条锈性由1对显性纯合基因控制:而CI-9的抗条锈性则由1对隐性基因控制。为抗性基因的合理利用提供了重要的遗传信息。4.发现了一个新的抗条锈基因YrP81并利用分子标记定位于2BS。利用条锈菌优势小种CYR32,对小麦品系P81和川麦28杂交后代F₁、F₂群体进行抗性鉴定,基因等位性测定,并用SSR和RGAP对F₂群体进行了抗条锈基因的分子标记。结果表明,P81携带一个对CYR32表现免疫的显性抗病基因;等位性测定结果表明该基因不同于Yr5、Yr10、Yr15和Yr26,暂定名YrP81。筛选到Xgwm429_251bp、WMC25_230/170bp、WMC770_180bp和Xgwm148_260bp等4个SSR标记与抗条锈基因YrP81紧密连锁,遗传距离分别为2.3cM、19.7cM、3.5cM和5.0cM。这4个SSR标记引物均位于2BS上,因而YrP81位于2BS上。从586对简并RGAP引物中筛选到2个标记RGAl_250bp（NLRR/XLRR）和RGA2_235bp（Pto kin4/NLRR-INV2）与YrP81连锁,遗传距离分别为3.5cM和5.2cM。抗性基因与标记之间的连锁关系为:-WMC25-RGA2-RGA1-Xgwm429-YrP81-WMC770-Xgwm148-着丝点-。根据抗性鉴定、系谱来源和分子诊断的结果,表明YrP81不同于目前已定位在2BS上的Yr27、Yr31和YrCN19,YrP81是一个新的抗条锈病基因。5.发现了一个新的抗条锈基因YrICA56并利用分子标记定位于2DS。源自叙利亚小麦品系ICA56对小麦条锈菌优势生理小种CYR30、CYR31、CYR32均表现免疫反应。利用CYR32对川麦28/ICA56的正交、反交F₁代以及F₂代分离群体进行抗病鉴定,结果表明ICA56的抗条锈性受单显性核基因控制。基因等位性测定表明,ICA56中所含抗性基因不同于Yr5、Yr10、Yr15和Yr26,暂将该基因定名为YrICA56。利用SSR标记对YrICA56基因进行了定位与作图,结果发现5个SSR标记Xgwm296_242bp、Xgwm210_287bp、Xgwm261_190bp、WMC503_310bp和WMC112_220bp与YrICA56基因连锁,遗传距离分别为7.0cM、14.1cM、10.4cM、16.6cM和4.5cM。YrICA56基因与分子标记之间的连锁关系为:-WMC503-Xgwm261-Xgwm296-YrICA56-WMC112-Xgwm210-着丝点-,并将YrICA56定位在2D短臂上。通过YrICA56与已定位在2DS上的抗条锈基因Yr16和YrKat进行比较,Yr16为成株期抗性,YrKat属温敏抗性,而YrICA56在苗期和成株期对条锈病均表现免疫反应,且其抗性的表达不受环境温度的影响,由此推测,YrICA56是一个抗条锈病新基因。更多还原

【Abstract】 Wheat stripe rust,caused by Puccinia striiformis West.f.sp.tritici,is one of the most important wheat disease.China is a big wheat-growing country,and the highly epidemic region of wheat stripe rust.Wheat production in China is threatened by stripe rust.At present,the simplicity of stripe rust resistance background in wheat cultivars have not changed although a lot of cultivars and breeding lines have been released.Identification of stripe rust resistances in wheat cultivars or breeding germplasm is very important for wheat improvment with stripe rust resistance.The objectives of this paper were to identify the seedling stripe rust resistance genes,to investigate the inheritance of stripe rust resistance and to tag the stripe rust resistance genes.The following results were obtained.1.Evaluation on stripe rust resistance of common wheat germplasm.Using three prevalent races of yellow rust CYR31,CYR32 and mixed races,which included CYR30,CYR31, CYR32,Hy46 and Shuiyuan11,the stripe rust resisitance of 106 wheat lines were evaluated by inoculated races.It was found that 20 lines showed immunity or high resistance to all the races,and 26 lines showed moderately resistance to all the races, whereas 26 lines showed moderately susceptible to one of the tested races,and 33 lines showed highly susceptible to all races.In this study,the order of the virulence of the races was Mixed races＞CY32＞CY31.2.At first,Study on slow rusting in wheat infected yellow rust in Sichuan basin.A total of 51 wheat lines were tested with the mixed yellow rust races including CYR29,CYR30, CYR 31,CYR32 and shuiyuan11 during two consecutive seasons.Based on the disease curves,these wheat lines could be divided into 5 distinct groups,designed as G1-highly resistance type with final disease severity（FDS）below 10%,G2 and G3-slow rusting type with FDS ranging from 10%to 40%,G4-highly susceptible with FDS more than 50%,and G5-high temperature resistance type.The FDS of G2,G3 and G4 types were closely related to the sowing time.Fourteen wheat lines with slow rusting and 6 lines with high-temperature resistance were indentified.FDS could be used as a reliable and simple indicator for the evaluation of slow stripe rust resistance in wheat breeding program.3.The inheritance of resistance genes in ICA31 and ICA70,which were derived from ICARDA（The international center for agricultural research in the dry areas,ICARDA, Syria）,were analyzed by inoculated with the prevalent stripe rust races CYR31 and CYR32.Two sets of populations of Chuanmai28/ICA31 and Chuanmai28/ICA70 were tested with two races.The phenotype of the F₁,F₂ and BC₁ seedlings were analyzed for resistance to stripe rust races.It was observed that the resistance of ICA31 to races CYR31 and CYR32 was both controlled by one dominant gene.The resistance of ICA70 to race CYR31 was controlled by the complementary action of one dominant gene and one recessive gene,while its resistance to race CYR32 was controlled by one recessive gene. The inheritance of resistance in CI-66 and CI-9 derived from CIMMYT were analyzed. The phenotype of the F₁,F₂ and BC₁ from Chuanmai28/CI-66 and Chuanmai28/CI-9 were analyzed for resistance to CYR32.The results showed that the resistance in CI-66 was controlled by one dominant gene,and the resistance of CI-9 was controlled by a couple of recessive gene.Thus,the expression of resistance gene in ICA70 is related with physical races and background of susceptible parents.4.A novel resistance gene Yrp81 was located on 2BS.For identification of seedling resistance gene in P81,F₁ and F₂ populations of the cross P81/Chuanmai28 were inoculated with CYR32.The resistance gene in P81 was allelic analysis with Yr5,Yr10, Yr15 and Yr26.The polymorphic SSR and RGAP primers between resistant and susceptible plants were used for genotyping the F₂ populations.Linkage analysis was conducted with the Mapmarker3.0.It was showed that P81 carried a single dominant resistance gene to CYR32,designated as YrP81,and YrP81 was different from Yr5,Yr10, Yr15 and Yr26 by allelism analysis.The resistance gene YrP81 was closely linked to four SSR loci on the 2BS with genetic distances WMC25-19.7cM,Xgwm429-2.3cM, WMC770-3.5cM and Xgwm148-5.0cM.From 586 RGAP primers,we screened out two RGAP makers linked with YrP81 at genetic distance RG1（NLRR/XLRR）-3.5cM and RG2（Pto kin4/NLRR-INV2）-5.2cM,respectively.The order of centromere,markers and gene was -WMC25-RGA2-RGA1-Xgwm429-YrP81-WMC770-Xgwm148-centromere-.At present,three stripe rust resistance genes（i.e.Yr27,Yr31 and YrCN19）have been located on 2BS.Yr27 and Yr31 were viruses to CYR31 and CYR32.YrP81 was different from Yr27 and Yr31 in resistance reaction,and different from YrCN19 at molecular markers and pedigree origin,suggesting that YrP81 is a new stripe rust resistance gene.5.A new resistance gene YrICA56 was located on 2BS.There was a dominant gene in ICA56 derived from ICARDA to CYR32 by the evaluation of F₁ and F2 population from Chuanmai28/ICA56,and this gene was difference with Yr5,Yr10,Yr15 and Yr26 by allelism analysis.The resistence gene in ICA56 was designated as YrICA56,and it was tagged by using F₂ population developed from Chuanmai28/ICA56.After screening 183 wheat microsatellite primers,it was found that five markers were linked to the resistance gene YrICA56 with genetic distance Xgwm296-7.0cM,Xgwm210-14.1cM, Xgwm261-10.4cM,WMC503-16.6cM,and WMC112-4.5cM.The order among centromere, markers and gene is -WMC503-Xgwm261-Xgwm296-YrICA56-WMC112-Xgwm210 -centromere-.Based on the results of mapmaker 3.0 and MapDraw 2.0,the resistance gene-YrICA56 is located on 2DS.The stripe rust resistance genes Yr16 and YrKat had been located on 2DS,while Yr16 is an adult resistance gene and YrKat is temperature sensitive. Therefore,it suggested that YrICA56 could be a new stripe rust resistance gene.更多还原