【作者】 但佳筠；

【导师】 张怀渝；

【作者基本信息】 四川农业大学 ， 生物物理学， 2009， 硕士

【摘要】 小麦条锈病、白粉病和赤霉病是世界性病害,也是我国小麦的三大主要病害。培育抗病品种是防治病害最为经济、有效和环保的方法,而鉴定和筛选优质抗源及抗病基因是抗病育种的基础和长期而艰巨的任务。栽培黑麦（Secale cereale L.）是小麦的重要近缘种属植物,携带有大量抗病、抗逆、增产基因。在近30年的小麦改良育种研究中,小麦—黑麦异染色体系作为向小麦遗传背景中导入黑麦外源遗传物质的桥梁材料,在小麦育种材料的创制中有不可取代的地位。本研究以小麦—黑麦远缘杂交（My15×Rw）BC₂F₄后代单株系为研究材料,Rw为中国栽培白粒黑麦（S.cereale L.cv.Baili）自交系,免疫白粉病,为抗源供体;My15为不含黑麦遗传背景的高感白粉病、条锈病的小麦品种。通过对94个供试材料的抗白粉病、条锈病和赤霉病特性的鉴定,筛选出具有优良抗病性的小麦—黑麦易染色体系,并通过分子细胞学研究和农艺性状考察,对抗病材料的黑麦外源种质进行了鉴定。研究结果如下:1.通过田间接种鉴定材料成株期条锈病、白粉病和赤霉病抗性,筛选出单抗白粉病材料37个,双抗条锈病、白粉病材料52个和兼抗条锈病、白粉病、赤霉病三种病害的材料1个。2.应用根尖有丝分裂细胞染色体计数,筛选出8个抗病性良好、且细胞学具有代表性的材料,分别是:911-1（2n=42）高抗白粉病,669-2（2n=42）、900-4（2n=42）、900-5（2n=44）、909（2n=42）、912（2n=42）和1014-1（2n=56）兼抗条锈病和白粉病,1016-2（2n=44）兼抗条锈病、白粉病和赤霉病。3.对筛选出的8个抗病材料进行减数分裂细胞染色体配对分析,结果显示:抗病材料在细胞学上均达到稳定。通过C—分带、GISH和SSR分析得知,669-2、909和911-1分别导入除一对1R、2R、3R以外的12条黑麦染色体,是缺失1R或2R或3R的小麦—黑麦不完全异染色体系,染色体构型分别为6”（2-7）R+15”W,6”（1,3-7）R+15”W和6”（1,2,4-7）R+15”W。900-4、900-5、912、1014-1和1016-2均导入黑麦1R—7R染色体14条,其中900-4和912的一组小麦染色体被黑麦染色体替换,已构成六倍体的小黑麦;900-5和1016-2的一组小麦染色体被黑麦染色体替换,并附加一对小麦染色体,是六倍体小黑麦小麦附加系;而1014-1是一个新的八倍体小黑麦。4.A-PAGE分析结果表明,除了669-2和900-4外,其余材料都具有黑麦碱特征带,其中669-2不含1R染色体而900-4含有1R染色体。900-4中1R染色体上的黑麦碱基因Sec-1表达缺失。5.田间主要农艺性状考察结果显示,与亲本普通小麦My15和白粒黑麦Rw相比,供试材料遗传了Rw分蘖成穗率高、小穗数多、穗长较长等优势,而株高和产量性状优于Rw,具有明显的杂种优势效应。本研究表明,中国栽培白粒黑麦Rw中含有抗条锈病、白粉病及赤霉病基因,可作为小麦抗病高产改良的优质抗源,选育出的8个抗病材料不仅可作为多抗、高产遗传研究的初级中间材料,还可作为饲用或粮用小黑麦进一步利用。更多还原

【Abstract】 Stripe rust,powdery mildew and Fusarium head blight（FHB） are major wheat diseases in China and all around the world.Developing resistance varieties is the most economical,effective and environmental way to control disease.Screening and identification of reisitance materials and genes is the foundation and also a long-term and arduous risk of wheat resistance breeding.As a related specie of wheat,rye（Secale cereale L.） carries a great number of resistant genes and increasing yield genes.In recent decades, as a bridged tool to translocate rye genetic material to wheat genetic background, Wheat-rye addition lines play an important role in wheat breeding.In this research,offsprings of hybrids BC₂F₄ between wheat My15 and rye Rw were taken as test materials.Rw as the donor parent was a Chinese Baili rye（S.cereale L.cv. Baili） inbred lines with resistance to stripe rust,powdery mildew.My15 as the receptor parent was a common wheat cultivar without any rye chromatin,which was high sensitive to stripe rust,powdery mildew and FHB.Through evaluation on disease resistance and molecular cytogenetics analysis,we selected materials with resistance to stripe rust, powdery mildew and（or） FHB,and detected the rye chromatin contained in the wheat background.The main results are summaried as follows:1.Evaluation on stripe rust,powdery mildew and Fusarium head blight resistance showed that there were 37 marterials had resistence to powdery mildew,52 materials had simultaneous resistance to stripe rust and powdery mildew,1 material had multi-resistance to stripe rust,powdery mildew and FHB.2.Based on the results of chromosome karyotype analysis and evaluation on disease resistance,we selected 8 materials with disease resistance.They were 911-1（2n=42） which was highly resistant to powdery mildew,669-2（2n-42,）900-4（2n=42）,900-5（2n=44）, 909（2n=42）,912（2n=42） and 1014-1（2n=56） which were simultaneous resistant to stripe rust and powdery mildew,and 1016-2（2n=44） which was multi-resistant to stripe rust, powdery mildew and FHB.3.All 8 selected materials were cytologic satble through the results of reduction division of pollen mother cells.Results of C-banding,GISH and SSR analysis demonstrated that all 8 materials contained rye chromatins.669-9,909,911-1 each had 12 rye chromsomes,lacking of one pair of 1R,2R and 3R chromsomes respectively.They were partial amphiploid,their chromosome configuration were 6"（2-7）R+15"W, 6"（1,3-7）R+15"W and 6"（1,2,4-7）R+15"W respectively.900-4,900-5,912,1014-1 and 1016-2 had 1R-7R all 14 rye chromsomes.900-4,909 and 912 were hexoploid triticale,in which one group of wheat chromosomes were replaced by rye chromosomes.900-5 and 1016-2 were wheat-hexoploid triticale addition lines,in which one group of wheat chromosomes were replaced by rye chromosomes and a pair of wheat chromosomes. 1014-1 were octoploid triticale,which contained wheat and rye all 56 chromosomes.4.A-PAGE result revealed that,beside 669-2 and 900-4,6 materials contained Sec-1 locus.900-4 had a pair of 1R chromsomes,but the Sec-1 locus from 1R of rye was absent in the A-PAGE pattern,which indicated 900-4 is a wheat-rye amphiploid with secalin absence.5.The results of main agronomic traits assessment indicated that,test materials had obvious effect of heterosis.Compared to the parents,matrials inherited advantages from both My15 and Rw,such as strong ability of tiller-earing,more spikelets and longer spike.The research indicated that the resistanc to to stripe rust,powdery mildew and Fusarium head blight of test martsrails came from Chinese Baili rye cultivar Rw,which could be used as a valuable resistance parent for wheat improvment.The 8 selected materials had high application value,they could be utilized not only as a fine germplasm of disease resistance in wheat breeding but also as forage and grain triticale.更多还原