不同簇毛麦6VS染色体臂的白粉病抗性特异功能标记的开发及应用

小麦6VS·6DL易位系Pm97033和6VS·6AL易位系92R137中的6VS染色体臂来自不同的簇毛麦种质,均表现良好的白粉病抗性,本研究利用分子标记对这2个易位系所包含抗病基因的异同进行了鉴定。利用与Pm21抗白粉病相关的丝氨酸/苏氨酸蛋白激酶Stpk-V基因(GenBank登录号为HQ864471.1)的基因组和cDNA序列为基础,在包含至少1个内含子的2个编码区设计引物,从Pm97033中扩增获得特异的多态性片段。为进一步提高特异性和扩增的稳定性,对特异扩增片段测序并重新设计引物,扩增筛选获得2个引物对,其中PK-F1/PK-R可专一扩增6VS·6DL易位系Pm97033及其抗病亲本,而PK-F2/PK-R可同时特异扩增2个不同来源的簇毛麦6VS染色体,但二者间的特异片段具有多态性。利用这2对引物,对系谱中包含6V(6D)和6VS·6AL、抗白粉病的小麦品系CB037进行检测,发现仅出现与6VS·6AL易位系相同的簇毛麦扩增片段,不存在簇毛麦No. 1026 (Pm97033的6VS供体)的扩增片段。基因组原位杂交结果表明,CB037仅含1对小麦-簇毛麦的易位染色体,用已报道的分子标记检测证明易位涉及的小麦染色体为6A,与本研究开发的分子标记检测结果相吻合,表明CB037携带的白粉病抗性基因来自6VS·6AL易位系92R137,其白粉病抗性可能与Pm97033具有不同的遗传基础。     

小麦-簇毛麦染色体代换系、易位系Ⅴ染色体RAPD标记筛选

利用105条S系列和100条Operon随机引物,对小麦一簇毛麦代换系(6V／6A)、两个易位系(6VS／6AL,6VS／6DL)及亲本簇毛麦(VV)、硬粒小麦(AABB)、栽培小麦(AABBDD)的多态性进行了筛选分析。80．95％的S系列引物扩增出了结果,且条带较清晰;在100条OP系列引物中均扩增出结果,条带清晰可见。从205个随机引物中发现,只有1个引物OPW03在含有簇毛麦V染色体的4个材料中均扩增出l条约570bp的谱带,而在栽培小麦和硬粒小麦中没有发现。因此,可以推测这个分子标记(OPW03—570)是位于簇毛麦V染色体短臂上的。     

簇毛麦6V染色体短臂特异分子标记的开发和应用

为开发簇毛麦6V染色体短臂特异的分子标记,并利用这些标记对缺失系进行鉴定,选用11个RGA和17对STS引物进行多态性分析,其中1个RGA引物和1对STS引物在对普通小麦扬麦5号、簇毛麦及普通小麦-簇毛麦6VS/6AL易位系进行多态性分析时,分别检测到一条约1 000 bp和约800 bp的多态性片段,将这两个标记转化为稳定的特异性分子标记,分别命名为CINAU17-1086和CINAU18-₇₂₃。运用这两对引物对一系列材料进行扩增,只有含6V染色体短臂的材料才能扩增出相应的特异条带,表明这两个标记均位于簇毛麦6VS上。进一步利用簇毛麦6VS缺失添加系、易位系将CINAU17-₁₀₈₆标记定位在簇毛麦6VS FL0.58与FL0.70之间,将CINAU18-₇₂₃标记定位在簇毛麦6VS FL0.45与着丝粒之间。利用这两个特异标记对通过花粉辐射获得的部分簇毛麦6VS结构变异材料进行PCR鉴定,其结果与细胞学鉴定结果一致。CINAU17-₁₀₈₆和CINAU18-₇₂₃标记可用来快速检测和追踪导入普通小麦背景中的簇毛麦6VS染色体片段,并对缺失系的断点进行了初步界定。     

小麦白粉病新抗源——基因Pm21

利用C-分带技术,从(扬麦4号或扬麦5号×6V代换系)F_2或M_3代选择的100个抗白粉病单株中,鉴定出17株涉及6VS/6AL易位。易位断点靠近着丝粒。易位系在MI平均每个PMC有0.00—0.80Ⅰ和20.69—21.00Ⅱ,易位染色体在中期Ⅰ基本配对成环状二价体,在细胞学上已稳定。不同小种不同菌系的白粉病鉴定表明,易位系在苗期和成株期均表现对白粉病免疫。在簇毛麦6VS上的抗白粉病基因不同于现有抗性基因,根据McIntosh的建议已将该基因定名为Pm21,并被收录于第八届IWGS小麦基因目录中。     

簇毛麦6VS特异转录序列P21461及P33259的获得及其分子标记在鉴定小麦-簇毛麦抗白粉病育种材料中的应用

簇毛麦6V#2S和6V#4S染色体臂分别携带抗白粉病基因Pm21和Pm V,在与小麦的杂种后代中,抗病基因与外源染色体臂共分离。开发鉴定2条外源染色体臂间多态性的序列,尤其是遗传信息相对缺乏的6V#4S染色体臂的序列,对于其在遗传与育种上的应用具有重要意义。本研究以携带6V#4S·6DL染色体的小麦易位系Pm97033及感病小麦亲本宛7107接种白粉菌的叶片转录组数据为资源,通过差异基因筛选、共线性分析、簇毛麦基因组扩增及测序验证的方法,鉴定出来自6V#4S的表达序列P21461和P33259,其中基于P21461序列设计的引物P461-5在簇毛麦6V#2S和6V#4S染色体臂的扩增产物具有30 bp的In Del和4 nt的多态性。用该引物转化的标记P461-5a可以鉴定抗白粉病小麦品种和高代品系所含的外源染色体,显示其在簇毛麦抗源鉴别和小麦抗病育种辅助选择中潜在的应用价值。根据P33259开发的标记P259-1可以对含有6V#4S染色体臂的材料进行特异扩增,但对6V#2S·6AL易位染色体没有扩增产物,因此P259-1可作为6V#4S·6DL易位染色体的特异分子标记。q RT-PCR分析结果显示,P21461的表达不受白粉菌诱导,而P33259在接菌后12 h和24 h的转录水平比接菌前提高约2倍,推测其可能参与Pm97033与白粉菌的早期互作。     

普通小麦-簇毛麦易位系T4VS·4VL-4AL的选育与鉴定

利用染色体C-分带和基因组原位杂交分析,从普通小麦-簇毛麦4V染色体二体异附加系（DA4V）与普通小麦农林26-离果山羊草3C染色体二体异附加系（DA3C）杂种后代中选育出小麦-簇毛麦纯合易位系T4VS·4VL-4AL。SSR和RFLP标记分析表明,该易位染色体包括4VS、4VL近着丝粒部分区段和4AL顶端区段;该易位系具有良好的细胞学稳定性,结实正常,为杀配子染色体诱发形成的补偿型易位;易位系T4VS·4VL-4AL高抗梭条花叶病,是小麦抗病育种新种质。     

南京农业大学细胞遗传实验室简介

细胞遗传实验室为农业部于1990年首批批准的重点开放实验室。主任为植物遗传育种学家刘大钧教授。本室有教授3人,副教授5人,讲师5人,助教2人;其中博士5人,硕士5人。其具体研究内容为:1、研究小麦及其近缘物种的基因组,探明其亲缘关系及起源,为转移、利用外源有益基因提供依据;2、开展以染色体工程为主的植物遗传工程研究,将亲缘植物的染色体、染色体片段和有用基因导入栽培植物,创造优异的新种质资源;3、综合运用现代分子、细胞遗传学最新技术,开拓转移外源有用基因,为培育在育种目标上有重大突破的新品种、新品系服务。在5个方面取得了重大进展:1、利用染色体分带、分子原位杂交、端体测交和染色体配对分析以及RAPD分析等分子、细胞遗传学技术,从普通小麦“扬麦五号”与抗白粉病的小麦-簇毛麦6V代换系的F4代和辐射M3代中鉴定出抗白粉病的小麦-簇毛麦6VS/6AL的易位系。易位系所携来自簇毛麦的抗性基因已由国际小麦基因命名委员会定名为Pm21;2、在小麦抗赤霉病新抗源的筛选、鉴定、转移和利用研究中,在国际上首次发现鹅观草、纤毛鹅观草对小麦赤霉病具有高度抗性,选育出抗赤霉病的小麦-大赖草附加系3个,小麦-鹅观草附加系2个,小麦-纤毛鹅观草附加系1个;3、利用与小麦白粉病抗性基因紧密连锁的RFLP和R     

分子标记辅助选育小麦抗白粉病、优质高分子量麦谷蛋白亚基聚合体

现代小麦育种的目标是选育丰产、综合抗逆性好的优质小麦新品种,将分子标记技术与传统育种方法相结合可以大大提高育种效率.本研究利用与小麦抗白粉病基因Pm21紧密连锁的共显性PCR标记、以及优质高分子量麦谷蛋白亚基1Dx5 1Dy10特异的PCR标记对以小麦品种安农94212、安农92484为优质亲本和以抗白粉病小麦簇毛麦易位系为抗病亲本的杂交高代材料进行标记位点的检测,结合田间抗病性鉴定结果,筛选、培育出聚合有Pm21和1Dx5 1Dy10的抗白粉病小麦聚合体,为小麦抗病、优质育种提供了具有重要利用价值的中间材料.     

基于EST-PCR的簇毛麦染色体特异分子标记筛选及应用

为定位、转移和利用簇毛麦有益基因, 通过花粉辐射, 获得一批包括小麦-簇毛麦易位染色体的异染色体系。为了鉴定这批材料中的簇毛麦染色体身份, 根据水稻、小麦的EST序列合成了240对STS引物, 其中34对引物在普通小麦中国春与簇毛麦间存在多态性;进一步对亲本及簇毛麦二体异附加系进行PCR扩增分析, 标记CINAU32_-300可追踪簇毛麦1V染色体, 标记CINAU33_-280、CINAU34_-510、CINAU35_-1100、CINAU36_-380和CINAU37_-400可追踪簇毛麦2V染色体, 标记CINAU38_-250可追踪簇毛麦3V染色体, 标记CINAU39_-950和CINAU40_-800可追踪簇毛麦4V染色体, 标记CINAU41_-745和CINAU42_-1050可追踪簇毛麦5V染色体, 标记CINAU44_-765和CINAU45_-495可追踪簇毛麦7V染色体。加上本室已开发的2个6V染色体特异标记, 用这些簇毛麦特异分子标记鉴定辐射诱导材料的部分回交后代, 选育出小麦背景中只包含单条簇毛麦染色体的整套1V至7V染色体系, 同时有18条易位染色体的簇毛麦身份得到确定, 表明这些标记可以用来快速检测普通小麦背景中的簇毛麦染色体或染色体片段。     

基于改进的多色荧光原位杂交技术的染色体分析

为了提高多色荧光原位杂交(M-FISH)技术的鉴定效率,简化M-FISH操作程序,探索和建立新的M-FISH实验及观察体系,本研究以‘荆辉1号’（普通小麦辉县红-荆州黑麦双二倍体）、‘南农9918’（普通小麦-簇毛麦整臂易位系T6VS.6AL）、‘扬麦22’（普通小麦-簇毛麦整臂易位系T6VS.6DL）以及‘ST5V#4S-1’（普通小麦-簇毛麦小片段易位系）等为试验材料,以2个寡核苷酸探针[(GAA)₁₀、pAs1-1]和物种基因组DNA探针作混合探针进行M-FISH分析。结果表明在一次原位杂交中同时使用3种探针,既可以识别出小麦背景中所有的外源染色体或染色体片段,又可以根据(GAA)₁₀和pAs1-1在染色体上的杂交信号分布精确鉴定出小麦和外源染色体（片段）的具体身份。这种改进的M-FISH技术可有效用于小麦及其近缘植物染色体的鉴定,并有助于快速构建物种基于FISH的分子核型。     

一个花粉辐射诱导的小麦-簇毛麦相互易位染色体系的分子细胞遗传学研究

利用⁶⁰Co-γ-射线处理小麦-簇毛麦6V单体添加系花粉，并给中国春授粉，在一个M1单株减数分裂中期Ⅰ检测到一个由2条小麦-簇毛麦易位染色体和一条完整小麦染色体构成的三价体，说明参与易位的2个小麦片段均来自同一条小麦染色体，推测两条易位染色体由相互易位产生。将其中涉及外源大片段的易位染色体称为外源大片段易位（large alien segment translocation, LAST），涉及外源小片段的称为外源小片段易位(small alien segment translocation, SAST)。对后代中两个易位染色体均纯合的植株（LAST’’+SAST’’, 2n = 44）进行顺次C-分带和GISH研究，结果表明外源大片段易位染色体为T7BS-6VS•6VL，外源小片段易位染色体为T6VS-7BS•7BL，易位断点分别位于7B染色体短臂约FL0.60处及6V染色体短臂约FL0.70处。在M2代群体中检测到7种染色体组成类型，比例为3(LAST’’+SAST’’)∶20(LAST’+SAST’)∶2(LAST’’+SAST’)∶1(LAST’+SAST’’)∶1LAST’∶2SAST’∶22(0型)，其中外源大片段和外源小片段易位染色体往往相伴出现。抗病鉴定结果显示抗白粉病基因位于外源大片段易位染色体T7BS-6VS•6VL上。对LAST’+SAST’型（2n = 43）M₂代单株花粉母细胞减数分裂的GISH研究结果显示，88.5%的后期Ｉ或末期Ｉ细胞中出现T6VS-7BS•7BL和T7BS-6VS•6VL的共分离。此外，在个别后期Ｉ细胞中观察到外源大片段易位染色体T7BS-6VS•6VL发生落后和着丝粒断裂现象，并在LAST’型单株（2n =42）的自交后代中筛选到一个通过着丝粒断裂-融合产生的外源小片段插入易位T7BL•6VS-7BS，这为利用外源大片段易位进一步创制携带抗病基因的小片段插入易位提供了新的思路。还分别获得了T7BS-6VS•6VL和T6VS-7BS•7BL的纯合易位系。     

Development and identification of wheat–Haynaldia villosa T6DL.6VS chromosome translocation lines conferring resistance to powdery mildew

Three lines conferring resistance to powdery mildew, Pm97033, Pm97034 and Pm97035, were developed from the cross of Triticum durum-Haynaldia villosa amphidiploid TH3 and wheat cv.'Wan7107' via backcrosses, immature embryo and anther culture. Genomic in situ hybridization analysis showed that these lines were disomic translocation lines. Cytogenetic analysis indicated that the F1 plants of crosses between the three translocation lines and 'Wan7107' and crosses between the three translocation lines and substitution line 6V(6D) formed 21 bivalents at meiotic metaphase I. Aneuploid analysis with 'Chinese Spring' double ditelocentric stocks indicated that the translocated chromosomes were related to chromosome 6D. Biochemical and restriction fragment-length polymorphism (RFLP) analyses showed that the translocation lines lacked a specific band of 6VL of H. villosa compared with the substitution and addition lines but possessed specific markers on the short arm of the 6V chromosome of H. villosa. The three translocation lines lacked specific biochemical loci and RFLP markers located on chromosome 6DS. The results confirmed that Pm97033, Pm97034 and Pm97035 were T6DL.6VS translocation lines.     

用AFLP标记鉴定带有簇毛麦抗白粉病基因的小麦易位系

对４个小簇麦及小麦亲本和抗源供体簇毛麦进行了ＡＦＬＰ分析,确定了４个小簇麦是均含有一段簇毛麦ＤＮＡ的易位系。从得到的３个与该基因可能较紧密连锁的标记和７个不太紧密连锁的标记中,推测４个易位系中簇毛麦ＤＮＡ的长短不一样。文中还讨论了ＡＦＬＰ作为一种准确、快速鉴定易位系方法的可行性。     

Efficient development of Haynaldia villosa chromosome 6VS‐specific DNA markers using a CISP‐IS strategy

Development of effective molecular markers linked to Pm21 deriving from Haynaldia villosa is critical for wheat breeding of powdery mildew resistance. In this study, we designed 12 pairs of conserved‐intron scanning primers (CISPs), using intron‐containing conserved genes located on the short arm of Brachypodium distachyon chromosome 3 (3BdS) aligned with cDNA or expressed sequence tags (ESTs) of Triticeae crops. Of 12 CISP primer pairs, 11 amplified DNA both in H. villosa and in wheat, and four displayed H. villosa chromosome 6VS‐specific polymorphisms. Six non‐polymorphic DNAs were further sequenced for designing internal primers, and five additional 6VS‐specific markers were obtained. Of the total nine 6VS‐specific co‐dominant markers, six could effectively trace Pm21 in F₂ population derived from the hybrid between the T6AL.6VS line and ‘Yangmai 158’. This study demonstrated that Brachypodium genomic information could be powerfully utilized to develop molecular markers in H. villosa or other Triticeae species.     

河南小麦新育成品种(系)白粉病抗性鉴定与分子标记检测

利用华北地区流行的白粉菌菌株E09和E20,分别对河南省小麦新品种(系)区域和预备试验参试材料908份(2009—2013年度)和412份(2009—2012年度)进行苗期白粉病抗性鉴定,同时利用与Pm2、Pm4a、Pm8和Pm21基因连锁的分子标记检测相关抗病基因的分布。结果显示,抗E09的材料占21.9%(199/908),抗E20的材料占9.5%(39/412),同时抗E09和E20的材料仅占3.6%(15/412)。在908份供试材料中,580份含有1BL/1RS,占63.9%,含Pm8或新的1RS来源抗白粉病基因;另有2份材料含6AL/6VS来源广谱抗白粉病基因Pm21,8份可能携带Pm2,2份可能含有Pm4a;有6份材料可能含有多个抗白粉病基因。表明河南省近年育成的小麦新品种(系)依然含有对我国白粉菌菌系有效的抗白粉病基因,但抗源遗传基础较窄,部分已经或正在丧失抗性,应加快引进和利用新的多样化抗病基因资源。     

Molecular mapping and detection of the yellow rust resistance gene Yr26 in wheat transferred from Triticum turgidum L. using microsatellite markers

Yellow rust (stripe rust), caused by Puccinia striiformis Westend f. sp. tritici, is one of the most devastating diseases of wheat throughout the world. Wheat-Haynaldia villosa 6AL.6VS translocation lines R43, R55, R64 and R77, derived from the cross of three species, carry resistance to both yellow rust and powdery mildew. An F₂ population was established by crossing R55 with the susceptible cultivar Yumai 18. The yellow rust resistance in R55 was controlled by a single dominant gene, which segregated independently of the powdery mildew resistance gene Pm21 located in the chromosome 6VS segment, indicating that the yellow rust resistance gene and Pm21 are unlikely to be carried by the same alien segment. This yellow rust resistance gene was considered to beYr26, originally thought to be also located in chromosome arm 6VS. Bulked Segregation Analysis and microsatellite primer screens of the population F₂ of Yumai 18 × R55 identified three chromosome 1B microsatellite locus markers, Xgwm11, Xgwm18 and Xgwm413, closely linked to Yr26. Yr26 was placed 1.9 cM distal of Xgwm11/Xgwml8, which in turn were 3.2 cM from Xgwm413. The respective LOD values were 21 and 36.5. Therefore, Yr26 was located in the short arm of chromosome 1B. The origin and distribution of Yr26 was investigated by pedigree, inheritance of resistance and molecular marker analysis. The results indicated that Yr26 came from Triticum turgidum L. Three other 6AL.6VS translocation lines, R43, R64 and R77, also carried Yr26. These PCR-based microsatellite markers were shown to be very effective for the detection of the Yr26 gene in segregating populations and therefore can be applied in wheat breeding. This revised version was published online in July 2006 with corrections to the Cover Date.     

Comparative analysis of genetic effects of wheat‐Dasypyrum villosum translocations T6V#2S·6AL and T6V#4S·6DL

Wheat‐Dasypyrum villosum translocations T6V#2S·6AL and T6V#4S·6DL, carriers of Pm21 and PmV, respectively, confer high resistance to wheat powdery mildew. For better understanding of the difference in genetic effect between them, a RIL population was constructed based on the cross between “Yangmai 18” carrying T6V#2S·6AL and “Yangmai 22” carrying T6V#4S·6DL. Analysis of distribution of the translocations showed that T6V#2S·6AL is much more transmittable than T6V#4S·6DL. By comparing their effects on main agronomic traits, we firstly found that T6V#2S·6AL contributes greatly to top spikelet fecundity, but causes a decrease of 6.7%–10.5% of spike number. No stable effects of T6V#4S·6DL on agronomic traits were found, except for positive effect on plant height. Excitingly, a new recombinant, T6V#4S‐6V#2S·6AL carrying PmV, was screened and proved to have a higher transmission rate than the original translocation T6V#4S·6DL, which will greatly promote the utilization of PmV. The above conclusions of this research will provide important guidance for utilization of Pm21 and PmV more effectively, in wheat powdery mildew resistance breeding.     

Chromosome location and microsatellite markers linked to a powdery mildew resistance gene in wheat line 'Lankao 90(6)'

Wheat lines known as 'Lankao 90(6)', derived from the cross 'Mzalenod Beer' (hexaploid triticale)/'Baofeng 7228'//'90 Xuanxi', carry a recessive powdery mildew resistance gene temporarily named PmLK906 . Gene PmLK906 appears to be different from known wheat powdery mildew resistance genes. PmLK906 was tagged using microsatellite markers in a segregating population derived from the cross 'Chinese Spring'/'Lankao 90(6)21-12'. The dominant microsatellite marker Xgwm265-2AL was linked in repulsion with PmLK906 at a genetic distance of 3.72 cM, whereas the co-dominant Xgdm93-2AL was linked to PmLK906 at a genetic distance of 6.15 cM. Both markers were placed on chromosome arm 2AL using 'Chinese Spring' nulli-tetrasomic lines. The recessive PmLK906 has a different specificity to the dominant resistance alleles located at the Pm4 locus and appeared to be located to a locus different from Pm4 .