小麦品系西农1163-4抗叶锈病基因的遗传分析和分子作图#br#

【目的】小麦品系西农1163-4高抗小麦叶锈、条锈和白粉病,综合农艺性状良好。明确该小麦品系中所含的抗叶锈病基因及遗传特点,找到与其紧密连锁的分子标记,有利于抗病基因利用和培育抗病新品种。【方法】将西农1163-4与感病品种Thatcher杂交,获得F1、F2代群体,利用中国叶锈菌优势小种THTT进行苗期抗性鉴定和抗性遗传分析;采用SSR技术对西农1163-4所携带的抗叶锈基因进行分子标记研究,共筛选了1 273对SSR引物。【结果】小麦品系西农1163-4对多个叶锈菌小种具有良好的抗病性,对THTT的抗性是由1个显性基因控制,该基因暂命名为LrXi。获得了与LrXi紧密连锁的3个微卫星分子标记Xbarc8、Xgwm582、Xwmc269和1个STS标记(ω-secali/Glu-B3),将LrXi定位于小麦1BL染色体上。距离最近的2个微卫星位点是Xgwm582、Xbarc8,与抗叶锈基因间的遗传距离分别为2.3 cM和3.2 cM。【结论】LrXi位于1BL染色体,抗叶锈表现不同于所有已知抗叶锈病基因,该基因的发现将有利于丰富中国抗叶锈病基因资源,为培育持久抗病品种奠定基础。     

小麦品系西农1163-4抗叶锈病基因的遗传分析和分子作图

【目的】小麦品系西农1163-4高抗小麦叶锈、条锈和白粉病,综合农艺性状良好。明确该小麦品系中所含的抗叶锈病基因及遗传特点,找到与其紧密连锁的分子标记,有利于抗病基因利用和培育抗病新品种。【方法】将西农1163-4与感病品种Thatcher杂交,获得F1、F2代群体,利用中国叶锈菌优势小种THTT进行苗期抗性鉴定和抗性遗传分析;采用SSR技术对西农1163-4所携带的抗叶锈基因进行分子标记研究,共筛选了1 273对SSR引物。【结果】小麦品系西农1163-4对多个叶锈菌小种具有良好的抗病性,对THTT的抗性是由1个显性基因控制,该基因暂命名为LrXi。获得了与LrXi紧密连锁的3个微卫星分子标记Xbarc8、Xgwm582、Xwmc269和1个STS标记(ω-secali/Glu-B3),将LrXi定位于小麦1BL染色体上。距离最近的2个微卫星位点是Xgwm582、Xbarc8,与抗叶锈基因间的遗传距离分别为2.3 cM和3.2 cM。【结论】LrXi位于1BL染色体,抗叶锈表现不同于所有已知抗叶锈病基因,该基因的发现将有利于丰富中国抗叶锈病基因资源,为培育持久抗病品种奠定基础。     

小麦5DL上基于SNP序列的新SSR标记的开发

本文旨在利用粗山羊草的物理图谱及其基因组序列数据库开发普通小麦5DL上Xbarc320-Xwmc215区段与SNP紧密连锁的SSR标记(SNP-SSR)。对AT5D4910-AT5D5010之间的90个SNP位点进行了序列延伸和本地Blast,利用SSR Hunter软件查找SNP位点附近的SSR位点,并利用Primer5设计引物。结果共发现109个SSR位点。对其中的72个位点设计引物,得到了47个5DL上Xbarc320-Xwmc215区段的SNP-SSR标记。对新开发的标记,利用22个小麦品种及人工合成小麦材料、中国春缺体四体及DH群体进行了有效性、多态性的检测及染色体定位。结果表明,这些标记均能扩增出稳定清晰的带型,并且均定位与小麦5D染色体上;其中四个标记Xtdc11、Xtdc31、Xtdc38、Xtdc44整合到了豫麦57与花培3号群体的5DL图谱上。     

粗山羊草Y192中抗叶锈基因LrY192的SSR定位

 【目的】在粗山羊草(Aegilops tauschii)中寻找新的抗叶锈病基因,为抗病育种提供新种质。【方法】本研究对抗小麦叶锈病的粗山羊草Y192和感小麦叶锈病的Y2272进行杂交,通过F2代抗叶锈性分离情况确定可能含有的抗叶锈基因数量,应用分离群体分组法（bulked segregation analysis,BSA）筛选D染色体上与抗叶锈性相关的SSR标记,用MapChart软件构建遗传连锁图谱。利用分子辅助鉴定和抗叶锈表型分析推测Y192可能含有的抗叶锈基因。【结果】在接菌04-5-192(THNT)的杂交后代中F1代表现抗病,F2代表现3:1的抗感分离,表明该基因为一个显性抗病基因,将该抗病基因暂命名为LrY192。筛选到的3个SSR标记Wmc245、Xgwm296和Xgwm261与该基因的遗传距离分别为4.1、18.9和26.2 cM。根据连锁标记在小麦微卫星图谱的位置,LrY192被定位在2D染色体上。【结论】综合分析基因所在的染色体位置及抗病特性,认为LrY192是一个新的抗小麦叶锈基因,获得的SSR标记Wmc245可用于分子辅助选择。     

小麦RIL群体遗传连锁图谱的构建及其多态性分析

以普通小麦重组近交系(recombinant inbred lines,RIL)‘Q9086×陇鉴19’为作图群体,利用SSR标记构建小麦遗传连锁图谱.结果表明:通过选用2 187对SSR引物筛选出RIL群体双亲表现多态性的引物共405对,多态性频率为18.52%.不同类型SSR标记多态性频率从小到大依次为Xpsp(4.4%)相似文献   

小麦ILs群体SSR分子标记遗传连锁图谱构建

【目的】为小麦回交导入系(introgression lines,ILs)群体(‘晋麦47’ב西峰20’)构建简单重复序列(simple sequence repeats,SSR)标记遗传连锁图谱.【方法】通过小麦ILs群体160个株系对2 306对均匀分布在21条染色体上的SSR标记进行多态性筛选,利用筛选出的多态性SSR标记对该群体进行遗传多样性分析和遗传连锁图谱构建.【结果】该群体共筛选出442个多态性SSR标记,每个SSR位点平均遗传多样性指数(H′)为0.31,多态性信息量(PIC)为0.25.其中,B基因组和第Ⅲ同源群H′与PIC较高,而D基因组和第Ⅰ同源群较低.通过聚类分析,该群体160个株系可分为5大类群.利用多态性SSR标记构建了1套涵盖小麦21条染色体的遗传图谱,总长度5 857.39 cm,每条染色体的平均长度为277.27 cm,标记间的平均距离为13.25 cm.【结论】构建了1条可用于小麦复杂数量性状精细定位和分子标记辅助选择育种的遗传连锁图谱.     

小麦条锈菌中国鉴别寄主维尔中抗条锈病基因YrVir1的微卫星标记

【目的】明确中国小麦条锈菌重要鉴别寄主维尔的抗条锈病基因及其遗传特点,建立与其连锁的微卫星标记,将病菌小种监测和抗病性分析提高到基因水平。【方法】由维尔为基因供体转育而成的含有小麦重要抗条锈基因YrVir1的近等基因系Taichung29*6/YrVir1,用小麦条锈菌单胞菌系2E16对近等基因系Taichung29*6/YrVir1、轮回亲本Taichung29及其杂交后代进行遗传分析;选用YrVir1所在2B染色体上的141对引物对近等基因系和轮回亲本的基因组DNA进行SSR分析。【结果】近等基因系Taichung29*6/YrVir1对2E16的抗病性由1对显性基因控制;引物Xbarc349在近等基因系与轮回亲本间稳定扩增出特异性DNA片段,同时在近等基因系和基因供体维尔间存在相同扩增片段,经F2代群体200个抗、感单株检测证实,Xbarc349标记位点与抗条锈病基因YrVir1连锁,遗传距离为4.2 cm。【结论】Xbarc349引物扩增出的特异性DNA片段可作为抗条锈病基因YrVir1的SSR标记;根据小麦SSR遗传图谱,将YrVir1基因定位在小麦2B染色体上。     

小麦抗白粉病基因 Pm13的 SSR 标记筛选

为筛选与抗白粉病基因 Pm13紧密连锁的分子标记,以携带 Pm13的抗病品系中大01与感病品系金光588为亲本进行杂交,获得 F1、F2分离群体和 F2：3家系,利用分离群体分组分析法（BSA）进行 SSR 标记分析。结果表明,中大01携带的 Pm13基因位于3BS 染色体,5个 SSR 标记BE398268、wmc674、cfa2226、gwm533．1和 BE471274与 Pm13连锁,遗传距离分别为0·5、0·8、1·6、13·2、52·1 cM,其中紧密连锁的标记 BE398268、wmc674和 cfa2226可用于该基因的分子标记辅助选择。     

小麦品种中梁16的抗条锈性研究

小麦条锈病是小麦生产上最严重的世界性病害之一。小麦品种中梁16具有抗逆性强、高产、抗条锈性强等优良特性。为明确其抗条锈性遗传规律,利用条锈菌小种CYR30对中梁16与感病品种铭贤169及其杂交后代进行苗期抗条锈性遗传分析。结果表明,中梁16对CYR30小种具有良好的抗性,由1对显性基因控制,暂命名为Yr Zhong16。通过分子标记分析,获得了与Yr Zhong16连锁的4个SSR标记Xwmc696、Xgwm644、Xbarc95和Xgwm131。其中与Yr Zhong16最近的侧翼位点为Xgwm644和Xbarc95,其遗传距离分别是2.3和3.5 c M。根据SSR标记的定位结果,将Yr Zhong16定位在小麦染色体7BL上。这些与Yr Zhong16连锁的分子标记为利用中梁16抗条锈病基因进行抗病基因聚合和分子标记辅助育种奠定了基础。     

粗山羊草抗条锈病鉴定及抗病基因YrY212 SSR标记

【目的】粗山羊草是小麦野生近缘属种,是D基因组的供体,蕴含大量的抗病资源,是进行小麦遗传改良的重要遗传资源,明确其抗病基因的数量、类型、在染色体上的位置以及其与已知抗条锈病基因间的关系,挖掘抗条锈病新基因,为小麦育种提供优良抗病新种质。【方法】用离体叶和田间鉴定方法鉴别来自不同产地的38份粗山羊草的抗条锈病情况,对条锈病抗病性进行遗传分析,并利用SSR分子标记定位粗山羊草中的抗病基因。【结果】离体叶鉴定发现,有9份材料对条中29和条中31菌株免疫,占供试材料的23.68%;有6份材料高感或中感,占供试材料的15.79%,其余材料抗病等级不一致。田间混合菌种鉴定结果表明,有19份材料免疫,其中10份材料苗期感病但成株期抗病,占供试材料的26.32%。从粗山羊草(Aegilops tauschii (Coss.) Schmal)Y212中鉴定出1个显性抗小麦条锈病基因,暂定名为YrY212。应用分离群体分组法(BSA)筛选到Wmc506、Barc184、Wmc450和Cfd41标记,其与YrY212之间的遗传距离分别为3.0,4.0,7.0和20.0 cM,位于Wmc506和Barc184之间。【结论】根据连锁标记所在小麦微卫星图谱的位置,YrY212被定位在7DS染色体上,分析基因所在染色体的位置、抗病性特征认为,YrY212是一个新的抗小麦条锈病基因。     

Molecular mapping of stripe rust resistance gene YrH9017 in wheat-Psathyrostachys huashanica introgression line H9017-14-16-5-3

Several new stripe rust pathogen races emerged in the wheat growing regions of China in recent years. These races were virulent to most of the designated wheat seedling resistance genes. Thus, it is necessary and worthwhile to identify new valuable resistant materials for the sake of diversifying resistant sources, pyramiding different resistance genes and achieving durable resistance. Here, we identified the resistance gene, temporarily designated as YrH9017, in wheat-Psathyrostachys huashanica introgression line H9017-14-16-5-3. A total of 146 F₂ plants and their derived F_2:3 families in a cross of Mingxian 169 and H9017-14-16-5-3 were used to evaluate seedling stripe rust response and as a mapping population. Finally, we constructed a genetic map including eight simple sequence repeat (SSR) markers and expressed sequence tag (EST) markers. YrH9017 was located on the long arm of chromosome 2A and closely linked with two EST-sequence tagged site (EST-STS) markers BG604577 and BE471201 at 1.3 and 1.8 cM distance, respectively. The two closest markers could be used for marker-assisted selection of YrH9017 in breeding.     

中梁12小麦抗条锈病基因遗传分析与SSR分子定位

中梁12具有抗逆性强、适应性广、抗条锈性强等许多优良的生物学特性。为明确其抗条锈性及遗传规律,利用当前流行的中国条锈菌小种CYR30对抗病品种中梁12与感病品种铭贤169及其杂交后代代F1、F2、F3和BC1代进行苗期抗条锈性遗传分析,并对其抗条锈基因进行SSR分子标记。结果表明,中梁12对CYR30小种具有良好的抗性,由1对显性基因控制,暂命名为YrZh12。该基因与位于小麦7AL染色体上的4个SSR位点Xwmc695、Xcfd20、Xbarc121和Xbarc49连锁,其中最近的侧翼位点为Xcfd20和Xbarc121,其遗传距离分别是3.1cM和4.9cM。系谱分析YrZh12基因可能来自抗引655,由于7AL染色体上没有其他抗条锈病基因,YrZh12可能是一个抗条锈病的新基因。     

源于中间偃麦草的抗条锈基因YrCH223的遗传分析及SSR定位

CH223是一个衍生于中间偃麦草的多抗性小偃麦种质系,通过感病的小麦品种与八倍体小偃麦TAI7047杂交、回交选育而成。抗性鉴定表明,CH223对我国当前小麦条锈病的流行小种CYR32,CYR33均有良好抗性。利用CH223与感病品种(系)的F2,F2∶3和BC1抗性分离群体进行抗性遗传分析,发现其条锈病抗性来自中间偃麦草,且由1对显性基因控制,暂时命名为YrCH223。用CYR32对来自台长29×CH223的221个F2植株进行接种鉴定,并构建抗、感DNA池。共筛选738对SSR引物,发现5对共显性SSR标记与抗病基因连锁,位置顺序为:Xgwm540-Xbarc1096-YrCH223-Xwmc47-Xwmc310-Xgpw7272,遗传距离分别为21.9,8.0,7.2,12.5,11.3 cM。进一步利用中国春缺体-四体和双端体材料扩增鉴定,将YrCH223定位于小麦4B染色体的长臂上(4BL)。经F2∶3群体验证,5个标记与YrCH223连锁。迄今为止,在4BL上未发现有公开报道的抗小麦条锈病基因。因此,基于抗病基因所在的染色体位置与来源,推断YrCH223是一个新的抗条锈病基因。     

Inheritance and Molecular Mapping of Stripe Rust Resistance Gene Yr88375 in Chinese Wheat Line Zhongliang 88375

Stripe rust is one of the most important diseases of wheat worldwide. Inheritance of stripe rust resistance and mapping of resistance gene with simple sequence repeat （SSR） markers are studied to formulate efficient strategies for breeding cultivars resistant to stripe rust. Zhongliang 88375, a common wheat line, is highly resistant to all three rusts of wheat in China. The gene conferring rust disease was deduced originating from Elytrigia intermedium. Genetic analysis of Zhongliang 88375 indicated that the resistance to PST race CYR31 was controlled by a single dominant gene, temporarily designated as Yr88375. To molecular map Yr88375, a F2 segregating population consisting of 163 individuals was constructed on the basis of the hybridization between Zhongliang 88375 and a susceptible wheat line Mingxian 169; 320 SSR primer pairs were used for analyzing the genetic linkage relation. Six SSR markers, Xgwm335, Xwmc289, Xwmc810, Xgdmll6, Xbarc59, and Xwmc783, are linked to Yr88375 as they were all located on chromosome 5BL Yr88375 was also located on that chromosome arm, closely linked to Xgdmll6 and Xwmc810 with genetic distances of 3.1 and 3.9 cM, respectively. The furthest marker Xwmc783 was 13.5 cM to Yr88375. Hence, pedigree analysis of Zhongliang 88375 combined with SSR markers supports the conclusion that the highly resistance gene Yr88375 derived from Elytrigia intermedium is a novel gene for resistance to stripe rust in wheat. It could play an important role in wheat breeding programs for stripe rust resistance.     

Identification and genetic analysis of multiple P chromosomes of Agropyron cristatum in the background of common wheat

Agropyron cristatum, a wild relative of common wheat (Triticum aestivum L.), provides many desirable genetic resources for wheat improvement, such as tolerance to cold, drought, and disease. To transfer and utilize these desirable genes, in this study, two wheat-A. cristatum derivatives II-13 and II-23 were identified and analyzed. We found that the number of root tip cell chromosomes was 44 in both II-13 and II-23, but there were four and six P genome chromosomes in II-13 and II-23, respectively, based on genomic in situ hybridization (GISH). The chromosome configurations of II-13 and II-23 were both 2n=22II by the meiotic analysis of pollen mother cells (PMCs) at metaphase I, indicating that there were two and three pairs of P chromosomes in II-13 and II-23, respectively. Notably, wheat chromosome 7D was absent in derivative line II-13 while II-23 lacked chromosomes 4B and 7A based on SSR analysis combining fluorescence in situ hybridization (FISH) analysis with pAs1 and pSc119.2 as probes. Chromosomes 2P and 7P were detected in both II-13 and II-23. Another pair of P genome chromosomes in II-23 was determined to be 4P based on expressed-sequences tags-sequence tagged sites (EST-STS) markers specific to A. cristatum and FISH with probes pAcTRT1 and pAcpCR2. Overall, these results suggest that II-13 was a 7P (7D) substitution line with one pair of additional 2P chromosomes and II-23 was a multiple 4P (4B), 7P (7A) substitution line with one pair of additional 2P chromosomes. Moreover, we obtained six alien disomic addition lines and five alien disomic substitution lines by backcrossing. These new materials will allow desirable genes from A. cristatum to be used in common wheat.     

普通小麦大赖草易位系T3AS·3AL-7Lr#1S的分子细胞遗传学鉴定

大赖草对赤霉病具有较好的抗性,将大赖草赤霉病抗性基因转入普通小麦,对拓宽小麦赤霉病抗性基础有重要意义。本研究在获得抗赤霉病普通小麦-大赖草异附加系基础上,采用1 200 R ⁶⁰Co-γ射线处理小麦-大赖草二体附加系DA7Lr花粉,授予已去雄的普通小麦中国春,对其后代(M₁)种子根尖细胞有丝分裂中期染色体进行GISH分析,获得了1株具有1条普通小麦-大赖草易位染色体的植株,让其自交,对自交后代中具有2条易位染色体植株的花粉母细胞减数分裂中期Ⅰ进行观察,发现2条易位染色体形成了稳定的环状二价体,表明该植株为纯合体。利用顺序GISH-双色FISH分析,结合C-分带、小麦D基因组专化探针Oligo-pAs1-2和B基因组专化探针Oligo-pSc119.2-2,进一步鉴定出该普通小麦-大赖草易位系为T3AS·3AL-7Lr#1S,且筛选出了可追踪该易位系的3个EST-STS分子标记BE591127、BQ168298和BE591737。该易位系的育成为小麦赤霉病遗传改良提供了新种质。     

簇毛麦易位系V9125-2抗条锈基因YrWV的遗传分析和SSR分子标记

[目的]对高抗条锈病的簇毛麦易位系V9125-2进行研究,明确其抗病性遗传特点,并对其抗条锈病基因定位,为选育优质抗源材料提供依据.[方法]采用中国当前流行的7个条锈菌生理小种CYR29、CYR30、CYR31、CYR32、CYR33以及Su11-4、Su11-11对簇毛麦易位系V9125-2和铭贤169的杂交后代进行...     

Molecular mapping of YrTZ2, a stripe rust resistance gene in wild emmer accession TZ-2 and its comparative analyses with Aegilops tauschii

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a devastating disease that can cause severe yield losses. Identification and utilization of stripe rust resistance genes are essential for effective breeding against the disease. Wild emmer accession TZ-2, originally collected from Mount Hermon, Israel, confers near-immunity resistance against several prevailing Pst races in China. A set of 200 F_6:7 recombinant inbred lines (RILs) derived from a cross between susceptible durum wheat cultivar Langdon and TZ-2 was used for stripe rust evaluation. Genetic analysis indicated that the stripe rust resistance of TZ-2 to Pst race CYR34 was controlled by a single dominant gene, temporarily designated YrTZ2. Through bulked segregant analysis (BSA) with SSR markers, YrTZ2 was located on chromosome arm 1BS flanked by Xwmc230 and Xgwm413 with genetic distance of 0.8 cM (distal) and 0.3 cM (proximal), respectively. By applying wheat 90K iSelect SNP genotyping assay, 11 polymorphic loci (consisting of 250 SNP markers) closely linked to YrTZ2 were identified. YrTZ2 was further delimited into a 0.8-cM genetic interval between SNP marker IWB19368 and SSR marker Xgwm413, and co-segregated with SNP marker IWB28744 (co-segregated with 28 SNP). Comparative genomics analyses revealed high level of collinearity between the YrTZ2 genomic region and the orthologous region of Aegilops tauschii 1DS. The genomic region between loci IWB19368 and IWB31649 harboring YrTZ2 is orthologous to a 24.5-Mb genomic region between AT1D0112 and AT1D0150, spanning 15 contigs on chromosome 1DS. The genetic and comparative maps of YrTZ2 provide a framework for map-based cloning and marker-assisted selection of YrTZ2.     

Genome-wide development of interspecific microsatellite markers for Saccharum officinarum and Saccharum spontaneum

Sugarcane has a large, complex, polyploid genome that has hindered the progress of genomic research and molecular marker-assisted selection. The user-friendly SSR markers have attracted considerable attention owing to their ideal genetic attributes. However, these markers were not characterized and developed at the genome-wide scale due to the previously lacking high-quality chromosome-level assembled sugarcane genomes. In this present study, 744305 and 361638 candidate SSRs were identified from the genomes of S. officinarum and S. spontaneum, respectively. We verified the reliability of the predicted SSRs by using 1200 interspecific SSR primer pairs to detect polymorphisms among 11 representative accessions of Saccharum, including S. spontaneum, S. officinarum, S. robustum, and modern sugarcane hybrid. The results showed that 660 SSR markers displayed interspecific polymorphisms among these accessions. Furthermore, 100 SSRs were randomly selected to detect the genetic diversity for 39 representative Saccharum accessions. A total of 320 alleles were generated using 100 polymorphic primers, with each marker ranging from two to seven alleles. The genetic diversity analysis revealed that these accessions were distributed in four main groups, including group I (14 S. spontaneum accessions), group II (two S. officinarum accessions), group III (18 modern sugarcane hybrid accessions), and group IV (five S. robustum accessions). Experimental verification supported the reliability of the SSR markers based on genome-wide predictions. The development of a large number of SSR markers based on wet experiments is valuable for genetic studies, including genetic linkage maps, comparative genome analysis, genome-wide association studies, and marker-assisted selection in Saccharum.     

小麦品种Bogatka抗白粉病基因的分子标记定位

为明确小麦品种Bogatka抗白粉病性状的遗传基础,利用感病亲本薛早和Bogatka以及其杂交所得"薛早/Bogatka"F1与薛早回交得到的BC1群体,进行遗传分析和分子标记定位。结果表明,Bogatka中含有1个显性抗白粉病基因,暂命名为MlBogatka。进一步利用BSA法对BC1分离群体进行分子标记检测,得到与MlBogatka基因连锁的分子标记STSBCD135、Xgwm501和Xwmc332,并构建遗传连锁图。根据这些分子标记的染色体定位信息,该基因位于小麦2B染色体长臂。综合对该基因的标记定位和Pm6基因特异分子标记检测结果,推测该基因可能是Pm6或与Pm6位点紧密连锁的抗白粉病基因。本研究结果为Bogatka在小麦抗白粉病育种中的利用提供了依据。