用RFLP鉴定普通小麦——纤毛鹅观草二体附加系中外源染色体的同源转 …

用小麦族７个部分同源群的４０个ＲＦＬＰ探针对小麦－纤毛鹅观草二体附加系进行分析，在证的有细胞学鉴定的基础上，又进一步提供了纤毛鹅观草染色体部分同源群的分子证据。即９６Ｋ０２５、９６Ｋ０２６中添 对纤毛鹅观草染色体Ｂ属于第２部分同源群；９６Ｋ０１２、９６Ｋ０１３中添加的一对染色体Ｅ属于第５部分同源群。对以上株系的衍生株系分析结果表明；染色体Ｂ、Ｅ在后代中可稳定传递。９６Ｋ０３０中添加的一对染色体Ｄ与     

普通小麦中国春-百萨偃麦草异染色体系的分子标记分析

综合利用HMW-Glu亚基、STS、SSR和RFLP等分子标记对普通小麦中国春、百萨偃麦草、中国春-百萨偃麦草双二倍体和11个中国春-百萨偃麦草异染色体系进行了分析。结果表明，14对SSR、10对STS引物和6个RFLP标记可以特异追踪百萨偃麦草染色质。C7-17及其后代株系C7-17-2等编码百萨偃麦草特异HMW-Glu亚基，添加染色体涉及与小麦第１部分同源群染色体部分同源的1J；1对STS、3对SSR和1个RFLP探针可以特异追踪二体附加系CH05中的百萨偃麦草染色体，并揭示最初根据分带核型确定的J3与小麦第2部分同源群染色体具有较高的部分同源性；2对STS、1个RFLP探针和1对SSR可以追踪CH09的外源染色体，并揭示最初确定的J7与小麦第3部分同源群染色体具有较高的部分同源性；1对STS和1个RFLP探针在CH03、CH04和CH34中具有相同的多态，3个附加系可能添加了相同染色体，最初确定的J₁、J₂和J_?与小麦第7部分同源群染色体具有较高的部分同源性；3对SSR引物可以特异追踪CH12中附加的大片段易位染色体和CH11中的小片段易位染色体，推测易位可能涉及同一条百萨偃麦草染色体。发现13个标记（5个STS、3个RFLP探针和5个SSR）可以追踪未涉及到的4J和5J等染色体。     

纤毛鹅观草原变种和竖立鹅观草变种居群间核型变异研究

纤毛鹅观草原变种与竖立鹅观草变种在我国广泛分布，是重要的小麦族野生种质资源。为了研究种间和居群间的染色体变异和遗传多样性，本研究对 15 份材料进行核型参数差异分析，发现所有材料均为中部着丝点染色体或近中部着丝点染色体，具 2 对随体染色体，分别为Ⅰ St 和 V Y ；平均臂比的变化范围为 1.21~1.40；染色体长度比的变化范围为 1.59~1.80；核不对称系数为 0.51~0.62，核型类型均为 2A。基于荧光原位杂交（FISH）的核型分析共发现 61 个 FISH 信号变异，其中 Y 染色体的变异（33）大于 St 染色体（28），构建居群间的“核心 FISH 核型”能对 14 对染色体进行区分。结果表明纤毛鹅观草原变种与竖立鹅观草变种居群在细胞核型数据和（FISH）核型上均存在丰富的多样性。     

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     

利用SSR鉴定普通小麦-多枝赖草二体异附加系 Line24中外源染色体同源群的归属

用227对小麦微卫星引物进行PCR扩增，76对可在多枝赖草和耐黄矮病的普通小麦-多枝赖草二体异附加系Line24的小麦亲本中国春、丰抗13间检测到多态性。和多枝赖草相同而与Line24其他小麦亲本不同的扩增带。在这76对引物中，发现有4对引物能从Line24中扩增出进一步用Line24和普通小麦杂交得到的7个不同的单体异附加系进行验证，也得到同样的结果，说明这4对微卫星引物扩增出的特异带可以作为Line24中多枝赖草染色体的分子标记。根据这4对引物各自对应的微卫星标记位点在小麦染色体上的位置，说明Line24中附加的一对多枝赖草染色体是第3，5，6和7部分同源群多枝赖草染色体相互易位形成的。     

普通小麦同源转化群3在染色体配对及可交配性方面的作用

米勒(Miller)等研究了中国春同源转化与群3黑麦(Secaleceral L)及球茎大麦(Hbulbosum)的杂种和普通小麦同源转化群3,非整倍单倍体的不同染色体配对水平。结果发现,普遍小麦同源转化群3染色体的长臂和短臂上都带有影响染色体配对的基因。     

小麦-偃麦草杂种后代及小麦种质资源对纹枯病的抗性

为鉴定小麦-偃麦草杂种后代以及我国小麦品种和育种中间品系对纹枯病的抗性,并且解析偃麦草染色体与纹枯病抗性的关系,在徐州和南京两个试点,采用田间病圃法对321份普通小麦品种或品系和56份小麦-偃麦草杂种后代材料进行了纹枯病抗性鉴定。在徐州试点没有发现高抗纹枯病的种质,但是有52份材料表现中抗反应型,包括34份普通小麦材料,其中萧农8506-1、小偃81、冀植4001、农大195、徐州8913和京东3066A-3的相对抗病指数高于0.7。在南京试点,全部普通小麦材料都不抗纹枯病,只有5份小麦-偃麦草种质表现中抗反应型。部分小麦-偃麦草种质的病情指数不但显著低于感病对照品种苏麦3号和扬麦158,而且还低于抗病对照品种安农8455和宁麦9号,如小麦-中间偃麦草4Ai#2或4Ai#2S附加系、代换系和易位系材料TA3513、TA3516、TA3517和TA3519及小麦-长穗偃麦草第4部分同源群染色体代换系SS767,说明中间偃麦草4Ai#2染色体和长穗偃麦草4J染色体可能与纹枯病病情指数降低有关。基因组原位杂交分析结果表明,4Ai#2染色体属中间偃麦草的J^s基因组,而长穗偃麦草与纹枯病抗性相关的第4部分同源群染色体属J基因组。虽然纹枯病与眼斑病的发病部位和症状非常相似,但抗眼斑病基因Pch1 (Madsen)和Pch2 (Cappelle-Desprez)对纹枯病无效。     

小麦地方品种“开县罗汉麦”在远缘杂交中的遗传评价

普通小麦(Triticum aestivum L.)是由A, B, D染色体组组成的六倍体物种。虽然这3个染色体组间存在部分同源关系,但是减数分裂中期的染色体配对只发生在同源染色体之间。这是由于普通小麦存在Ph(即Pairing homoeologous)配对调控系统。这个配对控制系统也同样抑制普通小麦与其外源属种的部分同源染色体间的配对,这也就阻碍了     

冬小麦种质矮孟牛第一部分同源群染色体遗传差异分析

由山东农业大学创制的矮孟牛是重要的冬小麦遗传资源。为了揭示矮孟牛种质第一部分同源群染色体的遗传差异,本研究利用分子标记和基因组原位杂交方法,对矮孟牛I型至VII型7个姊妹系的遗传差异进行了鉴定。PCR结果显示,矮孟牛II型、IV至VII型中含有1RS和1BL,不含1BS和1RL;I型和III型中含有正常的1B染色体。基因组原位杂交结果证明,在矮孟牛II型、IV型-VII型中1RS取代了1BS,而在矮孟牛I型和III型中含有正常的小麦染色体组。利用138个多态性标记分析了7个类型第一部分同源群的遗传差异,其中3个标记检测到矮孟牛V型的特异片段,即位于1A染色体的标记Xwmc336和Xmag1884及位于1B染色体的Xgwm124,分别源于牛朱特和矮丰3号。本研究结果揭示了矮孟牛7个类型第一部分同源群的遗传差异,为深入研究和利用该种质资源奠定了基础。     

普通小麦近缘物种黑麦1R、簇毛麦1V及鹅观草1Rk#1染色体特异分子标记的筛选

为筛选普通小麦近缘物种黑麦1R、簇毛麦1V及鹅观草1Rk^#1染色体特异分子标记，根据已定位于普通小麦第一部分同源群的EST序列设计104对STS引物，对中国春、鹅观草、黑麦及簇毛麦进行多态性分析。在104对STS引物中，有53对在对照普通小麦中国春与鹅观草、黑麦及簇毛麦之间存在多态性。利用普通小麦-黑麦1R~7R二体异附加系筛选出5对黑麦1R染色体特异标记，分别是CINAU 19-₅₀₀、CINAU20-₉₅₀、CINAU21-₁₅₀₀、CINAU22-₃₁₀和CINAU23-₂₀₀₀；利用普通小麦-簇毛麦1V~7V二体异附加系筛选出5对簇毛麦1V染色体特异标记，分别是CINAU23-₁₇₀₀、CINAU24-₁₀₅₀、CINAU25-₁₆₅₀、CINAU26-₅₀₀和CINAU27-₆₂₀；利用鹅观草二体异附加系DA1Rk^#1、异代换系DS1Rk^#1(1A)、端体系DA1Rk^#1L、易位系T1Rk^#1S·W、长臂缺失系Del1Rk#1L筛选出5对鹅观草1Rk^#1特异标记，分别是CINAU27-₉₆₀、CINAU28-₁₃₆₀、CINAU29-₄₈₀、CINAU30-₅₆₀和CINAU31-₅₂₀。研究表明，可以利用普通小麦的EST序列设计PCR引物，转化成STS标记，筛选普通小麦近缘物种黑麦、簇毛麦及鹅观草等染色体特异的分子标记，快速检测和追踪导入普通小麦背景中的黑麦1R、簇毛麦1V及鹅观草1Rk^#1染色体或染色体片段，为深入研究普通小麦远缘杂种材料提供新的工具。     

Isolation, identification and characterization of disomic and translocated barley chromosome addition lines of common wheat

Two disomic barley chromosome addition lines and five translocated chromosome addition lines of common wheat cultivar Shinchunaga were isolated. They were derived from a hybrid plant between Shinchunaga and cultivated barley Nyugoruden (New Golden) by backcrossing with wheat and self pollination. Barley chromosomes added to chromosome arms involved in the translocated chromosomes were identified by C-banding method and by crossing these lines with Chinese Spring/Betzes addition lines. Two disomic addition lines were identified to have chromosome 6 and 7 of barley, respectively. Two of the five translocated chromosome addition lines were clarified to have same chromosome constitution, 42 wheat chromosomes and a pair of translocated chromosomes constituted with a long arm of chromosome 5B of wheat and a short arm of chromosome 7 of barley. The other three lines could not be identified due to chromosome rearrangement. Performances of these seven lines on agronomic characters were examined. Addition of barley chromosome 7 induced early heading, and chromosome 6 showed lated heading. Almost all of the lines except that of chromosome 6 showed short culm length and all showed reduced number of tillers, spikelets and grains per ear, and low seed fertility. These lines would be useful for genetic analyses in wheat and barley and for induction of useful genes of barley into wheat. This revised version was published online in July 2006 with corrections to the Cover Date.     

应用GISH与STS标记鉴定小麦-中间偃麦草抗黄矮病端体系

由大麦黄矮病毒引起的小麦黄矮病毒病是一个严重病害,至今在小麦属内还没有发现抗源。中间偃麦草2Ai-2染色体携带一个高抗黄矮病基因,对该基因的染色体臂定位将为制定抗病基因向小麦转移策略,筛选、开发特定的、与抗性连锁的分子标记的研究提供重要信息。本文对由小麦-中间偃麦草二体附加系Z6衍生的3个抗黄矮病端体系进行鉴定,通过分析端体的遗传构成、筛选与端体共分离的STS标记以确定端体在遗传上的染色体臂归属,从而明确BYDV抗病基因的染色体位置。以拟鹅冠草基因组[Pseudoroegneria strigosa (M. Bieb.) Löve,St]DNA为探针,中国春基因组(Triticum aestivum L., ABD) DNA作封阻分别对抗病亲本Z6及抗病端体系N530的根尖体细胞染色体进行原位杂交,结果表明,N530体细胞中有2个端体显示出与Z6中外源染色体2Ai-2短臂相似, 而与长臂不同的杂交信号。以小麦第2同源群的5个RFLP探针的DNA序列为基础,设计了6对PCR引物,对小麦-中间偃麦草二体异附加系、二体代换系和端体系进行扩增,结果表明,基于短臂探针psr126,psr131序列设计的2对引物,可在含有2Ai-2染色体及端体的抗黄矮病材料中特异扩增,而基于长臂探针psr112序列设计的1对引物,可在含有2Ai-2染色体的抗黄矮病材料中特异扩增,但不能在端体系进行特异扩增,证明外源端体为2Ai-2染色体的短臂。本研究不仅将黄矮病抗性基因定位于2Ai-2染色体的短臂上, 而且由RFLP探针psr126、psr131和psr112序列转化的标记STS₁₂₆ (sequence tagged site) STS₁₃₁和STS₁₁₂还可分别作为追踪2Ai-2染色体短臂和长臂的分子标记,用于抗病易位系辅助选择。     

Identifying the alien chromosomes in wheat – Leymus multicaulis derivatives using GISH and RFLP techniques

Genomic in situ hybridization (GISH) and restriction fragment length polymorphism (RFLP) were used to identify the Leymus multicaulis (XXNN, 2n = 28) chromosomes in wheat-L. muliticaulis derivatives. Fifteen lines containing L. multicaulis alien chromosomes or chromosomal fragments were identified. All alien chromosomes or fragments in these 15 lines were from the X genome and none were from the N genome. Eleven L. multicaulis disomic addition lines and four translocation-addition lines were identified with chromosome rearrangements among homoeologous groups 2, 3, 6 and 7. Only homoeologous group 1 lacked rearrangements in addition or translocation chromosomes. The results revealed that translocation in non-homoeologous chromosomes widely exists in the Triticeae and therefore it is necessary to identify the alien chromosomes (segments) in a wheat background using these combined techniques. During the course of the work, probe PSR112, was found to detect X genome addition lines involving L. multicaulischromosomes. This may prove to be a valuable probe for the identification of alien chromosomes in a wheat background. This revised version was published online in August 2006 with corrections to the Cover Date.     

Characterization of wheat-alien translocations conferring resistance to diseases and pests: current status

Summary Wild relatives of common wheat, Triticum aestivum, and related species are an important source of disease and pest resistance and several useful traits have been transferred from these species to wheat. C-banding and in situ hybridization analyses are powerful cytological techniques allowing the detection of alien chromatin in wheat. C-banding permits identification of the wheat and alien chromosomes involved in wheat-alien translocations, whereas genomic in situ hybridization analysis allows determination of their size and breakpoint positions. The present review summarizes the available data on wheat-alien transfers conferring resistance to diseases and pests. Ten of the 57 spontaneous and induced wheat-alien translocations were identified as whole arm translocations with the breakpoints within the centromeric regions. The majority of transfers (45) were identified as terminal translocations with distal alien segments translocated to wheat chromosome arms. Only two intercalary wheat-alien transloctions were identified, one induced by radiation treatment with a small segment of rye chromosome 6RL (H25) inserted into the long arm of wheat chromosome 4A, and the other probably induced by homoeologous recombination with a segment derived from the long arm of a group 7 Agropyron elongatum chromosome with Lr19 inserted into the long arm of 7D. The presented information should be useful for further directed chromosome engineering aimed at producing superior germplasm.Contribution No. 96-55-J from the Kansas Experimental Station, Kansas State University, Manhattan, KS 66506-5502, USA.     

Transfer of powdery mildew resistance from Aegilops variabilis into bread wheat

Winter hexaploid wheat (Triticum aestivum L.) was crossed with Aegilops variabilis to transfer resistance to powdery mildew into wheat. Following two backcrosses to wheat and from 5 to 9 generations of selfing, several disomic addition and substitution lines of hexaploid wheat resistant to the mildew pathogen were isolated. A pair of short satellited chromosomes was always observed in the resistant lines. Further evidence utilizing as markers for homoeologous group 1 HMW glutenin subunits and DNA hybridization with probe pGBX 3076 showed that an alien substitution involved this homoeologous group.     

Chromosomal location of genes influencing plant characters and evapotranspiration efficiency in bread wheat

Little is known of genes that influence root development and drought resistance in bread wheat. The evapotranspiration efficiency (ETE = ratio of vegetative dry weight to total water used) of spring bread wheat tall landrace ‘Chinese Spring’ is relatively high. We used 42 ditelosomic and dimonotelosomic lines of Chinese Spring to identify chromosome arms that influence plant characters and ETE. Multiple regression analyses indicated that 96% of the variation observed in ETE was explained by variation in vegetative dry weight and total water used. Variation in plant height, number of spikes (tillers), root dry weight and shoot dry weight (excluding grains) together explained 88% of the variation observed in plant vegetative dry weight. Chromosome arms involved in expression of days to heading and maturity, plant height, number of spikes, root dry weight, shoot dry weight, number of grains, grain weight, and carbon isotope discrimination (Δ) were identified. Specifically, both arms of chromosome 2A, the long arm of chromosome 2B, and the short arm of chromosome 2D might carry genes with positive effects on number of spikes, root dry weight, and shoot dry weight. None of the aneuploids produced grain yield greater than Chinese Spring. The short arms of chromosomes 6A and 4D might carry genes that suppress Δ. Chromosome 1D might carry genes that increase relative water loss. The chromosome arms belonging to homoeologous group 2 might carry genes with positive effects on ETE. The genetic basis of ETE in modern wheats could be broadened by substituting specific chromosome arms of landrace wheats carrying desired characters into their genomes. This revised version was published online in July 2006 with corrections to the Cover Date.     

Transfer of the Glu-D1 Gene from Chromosome 1D of Breadwheat to Chromosome 1R in Hexaploid Triticale

The use of hexaploid triticale as a crop for human consumption has been limited by its inferior bread-making quality. To ameliorate this problem, a segment of chromosome ID of breadwheat with the Glu-D1d allele encoding for high molecular weight glutenin subunits 5 7plus; 10 was translocated to chromosome 1R of the hexaploid triticale ‘Rhino’ through a combination of a centric break-fusion translocation followed by 5D(5B)-induced homoeologous pairing. The resulting recombinant chromosome 1R has a small interstitial segment of ID with the Glu-D1d allele. The maximum physical length of the translocated segment is estimated at about 16.5 % of 1DL. Frequency of translocations involving the long arms of homoeologous group-1 chromosomes in the analyzed progeny suggested that homoeologous recombination in triticale was substantially higher than that previously reported in hexaploid wheat.     

A set of new 1RS translocations from wheat cv. Amigo in a uniform genetic background

Wheat-rye translocation 1RS.1AL from cv. Amigo is still popular in wheat breeding and commercial cultivars. It introduces several disease and pest resistance genes from rye into wheat, and appears to enhance root system development. To create a set of uniform stocks for precise tests, the rye arm 1RS was separated from the wheat arm in the translocation by misdivision of centromeres in univalents, fused into a complete chromosome 1R, and then re-translocated to all group-1 wheat chromosomes 1A, 1B and 1D, creating a set of three translocation and three substitution lines in a uniform background of cv. Pavon 76. Misdivision frequencies of the chromosomes mirrored those observed earlier in that shorter chromosomes broke less frequently than the long ones, and chromosomes from previous misdivision-fusion events misdivided more frequently than normal intact chromosomes. This set of chromosome lines with 1RS from cv. Amigo increases to three the number of such translocations stocks in wheat.     

Chromosomal location of genes for resistance to powdery mildew in <Emphasis Type="Italic">Agropyron cristatum</Emphasis> and mapping of conserved orthologous set molecular markers

Agropyron cristatum exhibits resistance to Blumeria graminis f. sp. tritici. Disomic and ditelosomic chromosome addition lines of A. cristatum in ‘Chinese Spring’ wheat were utilized to determine which A. cristatum chromosomes carry resistance gene(s). Resistance is conferred by gene(s) on chromosome arms 2PL and 6PL. The availability of molecular markers capable of detecting these chromosome arms in a wheat background would be very useful for marker-assisted introgression of 2PL and 6PL chromatin into common wheat. With this aim, 170 wheat conserved orthologous set (COS) markers (92 and 78 from wheat homoeologous groups 2 and 6 respectively) were assessed for their utility in A. cristatum. A total of 116 (68.2%) COS markers successfully amplified product in A. cristatum and 46 (40.0%) of these markers were polymorphic between A. cristatum and common wheat. From marker loci mapping on wheat homoeologous group 2 chromosomes, 23 markers (34.9%) were polymorphic between A. cristatum and common wheat and from them 13 markers were assigned to chromosome arm 2PL and six markers were mapped to chromosome 4P of A. cristatum showing that this chromosome is related to wheat homoeologous group 2. From marker loci mapping on wheat homoeologous group 6 chromosomes, 23 (46.0%) markers were polymorphic between A. cristatum and common wheat and from them 17 markers were located on chromosome 6P, six of them were mapped to chromosome arm 6PS and five to chromosome arm 6PL, respectively. The specific COS markers allocated on the long arms of chromosomes 2P and 6P may have a role in marker-assisted screening in wheat breeding for powdery mildew disease resistance.