普通小麦品种农大399抗白粉病基因SSR和AFLP-SCAR分子标记

小麦白粉病是由布氏禾白粉菌(Blumeria graminis f.sp.tritici)引起,在小麦生产上发生最广泛的世界性病害之一。普通小麦品种农大399(系谱为Torino/2*2552//9516/3/5*石4185)是利用"滚动式加代回交转育"育成的高产、抗白粉病新品种。利用农大399和高感白粉病小麦品种石4185进行杂交,获得农大399/石4185的F1、F2分离群体和F2:3家系。对F1、F2分离群体和F2:3家系进行了苗期抗白粉病鉴定和遗传分析,结果表明:农大399对白粉菌生理小种E09的抗性受l对显性基因控制,暂命名为MlND399。通过BSA和分子标记分析,获得了与MlND399连锁的1个SSR标记Xcfd81和2个AFLP-SCAR标记SCAR203和SCAR112。其中MlND399与Xcfd81的遗传距离为0.2 cM,与SCAR203的遗传距离为1.0 cM,与SCAR112的遗传距离为1.2 cM。根据SSR标记在中国春缺体-四体、双端体和缺失系中的定位结果,将MlND399定位在小麦染色体臂5DSBin 0.67～0.78区间上。根据对抗白粉病基因的染色体定位结果,推测MlND399是Pm2基因。这些与MlND399连锁分子标记为利用农大399的抗白粉病基因进行抗病基因聚合和分子标记辅助选择育种奠定了基础。     

小麦抗白粉病基因SSR标记定位

从波兰小麦与普通小麦感病品系‘中13’杂交后代中选育出小麦抗源材料WP6192,田间表现高抗白粉病,遗传分析表明其含有1对显性抗白粉病基因,暂定名为PmWP6192。用分离群体分组分析法筛选多态性SSR标记,并用F2代群体进行遗传连锁分析。结果表明,SSR标记Xgwm515、Xgwm249、Xgwm425、Xgwm372、Xg-wm630、Xbarc10、Xbarc220、Xbarc201和Xbarc353与PmWP6192基因连锁,相距最近的标记是Xbarc353,遗传距离为2.3cM。根据连锁标记所在的染色体位置,将PmWP6192定位于2AL染色体。通过基因来源分析和2AL染色体上已有抗白粉病基因的等位性分子检测,推断PmWP6192可能是1个新的抗白粉病基因。     

两系杂交小麦恢复系MR168抗条锈病基因遗传分析及分子标记定位

小麦条锈病是影响杂交小麦普及推广的重要因素。文章利用基因推导法和SSR分子标记技术,研究了温光型两系杂交小麦恢复系MR168的抗条锈性遗传规律及其控制基因染色体位置。结果表明,MR168对CY29、CY31、CY32、CY33等条锈菌生理小种表现高抗至免疫;对SY95-71/MR168杂交组合的正反交F1、BC1、F2和F3群体分单株接种鉴定显示,MR168对CY32号小种的抗性受1对显性核基因控制,该抗病基因来源于春小麦品种辽春10号。利用集群分离分析法(Bulked segregant analysis,BSA)和简单重复序列(Simple sequence repeat,SSR)分子标记分析抗病亲本MR168、感病亲本SY95-71及183个F2代单株,发现了与MR168抗条锈病基因连锁的5个微卫星标记Xgwm273、Xgwm18、Xbarc187、Xwmc269、Xwmc406,并将该基因初步定位在1BS着丝粒附近,暂命名为YrMR168;构建了包含YrMR168的SSR标记遗传图谱,距离YrMR168最近的两个微卫星位点是Xgwm18和Xbarc187,遗传距离分别为1.9 cM和2.4 cM,这两个微卫星标记可用于杂交小麦抗条锈病分子标记辅助育种。     

小麦品系19HRWSN-76的抗叶锈性研究

小麦叶锈病是影响小麦产量的最主要病害之一,CIMMYT品系19HRWSN-76高抗小麦叶锈病,以该品系与感病品系郑州5389杂交得到F2群体,利用叶锈菌生理小种FHJP对F2群体接菌鉴定,结果显示群体的抗感比例符合3∶1的理论比值,推测19HR WSN-76的抗叶锈性由一对显型基因控制,暂命名为Lr HR76。利用分子标记技术和分离群体分组分析法对F2群体进行分子标记检测,位于3DL的SSR标记barc71与该抗病基因连锁,遗传距离为3.0 c M。     

小麦品种冀麦24抗麦红吸浆虫QTL分析

麦红吸浆虫是影响小麦产量和品质的重要害虫,研究小麦对吸浆虫抗性的遗传及其连锁分子标记对于提高抗虫品种的选择效率具有重要意义。本研究以小麦感虫品系6218与抗虫品种冀麦24产生的重组近交系(RIL)群体为材料,利用SSR标记和人工虫圃对冀麦24的抗虫性遗传进行了研究。结果表明:6218与冀麦24的抗性差异显著,RIL群体在2年2点的鉴定中抗性稳定;所构建的遗传连锁图谱包含112个SSR位点,形成26个连锁群,图谱全长835.7 cM,标记间平均距离为7.5 cM。利用QTL IciMapping的完备区间作图法,在4A染色体上检测到1个加性效应位点(QSm.hbau-4A),该位点在2个鉴定年度的贡献率分别为9.67%、10.57%。该抗性QTL及其连锁SSR标记的发掘,将有助于提高小麦抗吸浆虫育种的选择效率。     

普通小麦Qz180中一个抗条锈病基因的分子作图

普通小麦(Triticum aestivum L.)材料Qz180具有良好的抗条锈病特性,经基因推导发现其含有一个优良的抗条锈病的基因,暂定名为YrQz.用Qz180与感病材料铭贤169和WL1分别杂交构建了两个F2群体,用条中30号条锈菌小种对这两个群体进行的抗性测验表明,YrQz为显性单基因遗传.通过SSR和AFLP结合BSA的方法对这个基因进行了分子作图,结果鉴定出与YrQz连锁的2个SSR标记和2个AFLP标记.根据SSR标记的染色体位置,该基因被定位在2B染色体的长臂上,位于两个SSR位点Xgwm388和Xgwm526之间;两个AFLP标记P35M48(452)和P36M61(163)分别位于该基因的两侧,遗传距离分别为3.4 cM和4.1cM.     

栽培一粒小麦3AA30中抗白粉病基因的鉴定及分子标记定位

栽培一粒小麦是普通小麦的近缘种,遗传多样性丰富,蕴含丰富的抗病基因,是小麦抗病性改良的重要资源。本文对栽培一粒小麦抗白粉病材料3AA30的抗白粉病基因进行了遗传分析和分子标记定位。结果表明,3AA30中含有一个隐性抗白粉病基因,暂命名为ml3AA30,找到了5个与该基因连锁的SSR分子标记Xgwm6、Xcfd39、Xcfa2185、Xcfa2141、Xcfa2155及2个STS标记Xmag2170、Xmag1491,并构建了ml3AA30的遗传连锁图,将该基因定位在小麦5A染色体长臂上。本研究为小麦抗病育种提供了新的抗源材料。     

普通小麦Qz180中一个抗条锈病基因的分子作图(英文)

普通小麦(Triticum aestivum L.)材料Qz180具有良好的抗条锈病特性,经基因推导发现其含有一个优良的抗条锈病的基因,暂定名为YrQz。用Qz180与感病材料铭贤169和WL1分别杂交构建了两个F_2群体,用条中30号条锈菌小种对这两个群体进行的抗性测验表明,YrQz为显性单基因遗传。通过SSR和AFLP结合BSA的方法对这个基因进行了分子作图,结果鉴定出与YrQz连锁的2个SSR标记和2个AFLP标记。根据SSR标记的染色体位置,该基因被定位在2B染色体的长臂上,位于两个SSR位点Xgwm388和Xgwm526之间;两个AFLP标记P35M48(452)和P36M61(163)分别位于该基因的两侧,遗传距离分别为3.4cM和4.1cM。     

小麦新抗源CH5383抗条锈病基因的遗传分析及分子定位

CH5383是新育成的源于中间偃麦草的渗入系,对小麦条锈病和白粉病均表现免疫。为明确其抗性来源、遗传方式和抗病基因在染色体上的位置,将CH5383的系谱材料及其与高感条锈病品种(系)杂交的F1、F2和F2:3家系群体进行条锈病抗性鉴定。结果表明,CH5383对条锈病的抗性源于中间偃麦草,对条锈病生理小种CYR32的抗性由一对显性核基因控制,将此基因暂时命名为YrCH5383。从476对SSR引物中筛选到3对引物Xgwm108、Xbarc206和Xbarc77与抗病基因连锁,遗传距离分别是8.2 cM、10.7 cM和13.6 cM。根据这两对标记在染色体上的位置,将抗病基因定位到3B染色体的长臂上。3B染色体的长臂还未见有正式命名的抗条锈病基因的报道,推测YrCH5383可能是一个源于中间偃麦草的新抗条锈病基因。     

兼抗白粉和条锈病小滨麦种质系山农6343的细胞学和SSR鉴定

利用抗性接种鉴定、细胞学和SSR分子标记技术相结合的方法,对从八倍体小滨麦和普通小麦烟农15杂种后代选育出的兼抗白粉病和条锈病的小滨麦种质系山农6343进行了鉴定.结果表明,山农6343的根尖细胞染色体数目2n=42,花粉母细胞减数分裂中期I(PMC MI)绝大多数细胞内可观察到21个二价体,平均染色体构型为2n=21Ⅱ,与普通小麦烟农15杂种F1的花粉母细胞内观察到2n=19Ⅱ+1Ⅳ的染色体构型,四价体出现频率为24.1%.利用SSR分子标记技术,在1283对SSR和EST-SSR引物中筛选出两对特异引物BARC236-4A和KSUM134,均能稳定地在山农6343中扩增出滨麦草的特异标记BARC236255和KSUM134245,且两个标记在小滨麦易位系山农0096中得到了验证.初步确定山农6343是一个小滨麦易位系.由于在目前已命名的小麦白粉病和条锈病抗性基因中尚未有来自滨麦草的,推测山农6343可能为新的白粉病和条锈病抗源,对小麦白粉病和条锈病的抗性遗传改良将具有重要的利用价值.     

一个来自硬粒小麦的抗白粉病基因的鉴定和微卫星标记

在起源于硬粒小麦(TriticumdurumDesf.accessionDR147)和尾状山羊草(AegilopscaudataL.acc.Ae14)合成的双二倍体与普通小麦品种“莱州953”杂交组合衍生的BC3F2群体中鉴定了一个抗小麦白粉病基因。遗传分析表明,该基因为一个显性单基因。应用分离群体分组法(BSA),鉴定了两个与抗病基因紧密连锁的微卫星标记Xgwm311和Xgwm382,它们与抗病基因的遗传距离分别为5.9cM和4.9cM。对双二倍体亲本硬粒小麦DR147和尾状山羊草Ae14及轮回亲本“莱州953”的DNAPCR扩增结果表明,与抗病基因相关的微卫星标记Xgwm311和Xgwm382来源于硬粒小麦DR147。根据已发表的小麦微卫星图谱和对“中国春”缺-四体系DNA扩增结果,抗病基因被定位在小麦2A染色体的长臂末端。     

一个来自硬粒小麦的抗白粉病基因的鉴定和微卫星标记

在起源于硬粒小麦(Triticum durum Desf.accession DR147)和尾状山羊草(Aegilops caudata L.acc.Ae14)合成的双二倍体与普通小麦品种"莱州953"杂交组合衍生的BC3F2群体中鉴定了一个抗小麦白粉病基因.遗传分析表明,该基因为一个显性单基因.应用分离群体分组法(BSA),鉴定了两个与抗病基因紧密连锁的微卫星标记Xgwm311和Xgwm382,它们与抗病基因的遗传距离分别为5.9 cM和4.9 cM.对双二倍体亲本硬粒小麦DR147和尾状山羊草Ae14及轮回亲本"莱州953"的DNA PCR扩增结果表明,与抗病基因相关的微卫星标记Xgwm311和Xgwm382来源于硬粒小麦DR147.根据已发表的小麦微卫星图谱和对"中国春"缺-四体系DNA扩增结果,抗病基因被定位在小麦2A染色体的长臂末端.     

Chromosomal location of a <Emphasis Type="Italic">Triticum dicoccoides</Emphasis>-derived powdery mildew resistance gene in common wheat by using microsatellite markers

The powdery mildew resistance has been transferred from an Israeli wild emmer (Triticum dicoccoides) accession "G-305-M" into common wheat by crossing and backcrossing (G-305-M/781//Jing 411*3). Genetic analysis showed that the resistance was controlled by a single dominant gene at the seedling stage. Among the 102 pairs of SSR primers tested, four polymorphic microsatellite markers (Xpsp3029, Xpsp3071, Xpsp3152 and Xgwm570) from the long arm of chromosome 6A were mapped in a BC(2)F(3) population segregating for powdery mildew resistance and consisting of 167 plants. The genetic distances between the resistance gene and these four markers were: 0.6 cM to Xpsp3029, 3.1 cM to Xpsp3071, 11.2 cM to Xpsp3152 and 20.4 cM to Xgwm570, respectively. The order of these microsatellite loci agreed well with the established microsatellite map of chromosome arm 6AL. We concluded that the resistance gene was located on the long arm of chromosome 6AL. Based on the origin and chromosomal location of the gene, it is suggested that the resistance gene derived from "G-305-M" is a novel powdery mildew resistance gene and is temporarily designated MlG.     

普通小麦99-2439 中的白粉病抗性遗传

普通冬小麦品系99-2439在郑州连续4年对田间白粉菌(Blumeria graminis sp. tritici)表现高抗,但其抗性基因来源不清。通过染色体C-分带和1RS染色体特异性SCAR标记鉴定, 表明它是一个小麦-黑麦(Triticum aestivum - Secale cereale)1BL/1RS异易位系。通过对中国春×99-2439杂交F2代分离群 体抗性鉴定和1RS染色体臂检测结果分析, 证明该抗病基因不在1RS染色体臂上。用单孢小麦白粉菌分离株对其抗性遗传进行研究, 结果表明, 99-2439的白粉病抗性由一对小种专化、隐性抗病基因控制。由于携带Pm5a的Hope/8Cc对中国的21个小麦白粉菌分离菌株均高度感病, 而99-2439高抗混和白粉菌和5个单孢分离菌株, 所以, 99-2439所携带的抗白粉病基因不同于Pm5a。     

普通小麦99-2439中的白粉病抗性遗传

普通冬小麦品系99-2439在郑州连续4年对田间白粉菌(Blumeria graminis sp.tritici)表现高抗,但其抗性基因来源不清.通过染色体C-分带和IRS染色体特异性SCAR标记鉴定,表明它是一个小麦-黑麦(Triticum aestivum-Secale cereale)lBL/1RS异易位系.通过对中国春×99-2439杂交F2代分离群体抗性鉴定和1RS染色体臂检测结果分析,证明该抗病基因不在1RS染色体臂上.用单孢小麦白粉菌分离株对其抗性遗传进行研究,结果表明,99-2439的白粉病抗性由一对小种专化、隐性抗病基因控制.由于携带Pm5a的Hope/8Cc对中国的21个小麦白粉菌分离菌株均高度感病,而99-2439高抗混和白粉菌和5个单孢分离菌株,所以,99-2439所携带的抗白粉病基因不同于Pm5a.     

QTLs for powdery mildew resistance in peach ×Prunus davidiana crosses: consistency across generations and environments

Powdery mildew, caused by Sphaerotheca pannosa var. persicae is one of the most important diseases in European peach orchards. Quantitative trait loci controlling powdery mildew resistance were detected using three related F1, F2 and BC2 populations derived from the cross between the resistant parent P. davidiana clone P1908 and the susceptible peach cultivar Summergrand. Powdery mildew resistance of each population was evaluated under natural exposure, in several locations and over several years. Thirteen QTLs were detected. For nine of them, the favourable allele came from the resistant parent. Five QTLs were consistently detected across the three populations. The F1 hybrid used to produce F2 and BC2 populations had not inherited the favourable allele from P1908 for QTL detected on LG3 and LG8 in F1 population. QTLs were not detected in the corresponding regions in F2 and BC2 populations. In two other genomic areas, significant substitution effects between P1908 alleles were evidenced in the F1 population, but the favourable allele came from Summergrand in the F2 and BC2 populations. Analysis of phenotypic data suggested an important qualitative change in the distribution of powdery mildew resistance after 1996, confirmed by QTL analysis. Indeed, a dramatic decrease of the effect of the major QTL previously detected on LG6 was observed after 1996, while the QTL on LG8 was increasingly involved in the control of powdery mildew resistance. Consequences for peach breeding strategies to improve powdery mildew resistance are discussed.     

Identification and development of diagnostic markers for a powdery mildew resistance gene on chromosome 2R of Chinese rye cultivar Jingzhouheimai

Chinese rye cultivar Jingzhouheimai (Secale cereale L.) shows a high level of resistance to powdery mildew. Identification, location, and mapping of the resistance gene would be helpful for developing a highly resistant germplasm or cultivar in wheat. Using sequential C-banding, GISH, and marker analysis, an addition chromosome with powdery mildew resistance was identified in a line derived from a cross between Chinese wheat landrace Huixianhong and rye cultivar Jingzhouheimai. The line, designated H-J DA2RDS1R(1D), had 44 chromosomes including two pairs of rye chromosomes, 1R and 2R, and lacked a pair of wheat chromosomes 1D, that is, it is a double disomic addition disomic substitution line. According to its reaction to different isolates of the powdery mildew pathogen, the resistance gene in H-J DA2RDS1R(1D) differed from the Pm8 and Pm7 genes located earlier on rye chromosomes 1R and 2R, respectively. In order to determine the location of the resistance gene, line H-J DA2RDS1R(1D) was crossed with wheat landrace Huixianhong and the F2 population and corresponding F2:3 families were tested for disease reaction and assessed with molecular markers. The results showed that a resistance gene, designated PmJZHM2RL, is located in rye chromosome arm 2RL.     

Identification and mapping of a new powdery mildew resistance gene on chromosome 6D of common wheat

Powdery mildew, caused by Blumeria graminis f. sp. tritici, is one of the most serious wheat diseases. The rapid evolution of the pathogen's virulence, due to the heavy use of resistance genes, necessitates the expansion of resistance gene diversity. The common wheat line D57 is highly resistant to powdery mildew. A genetic analysis using an F(2) population derived from the cross of D57 with the susceptible cultivar Yangmai 158 and the derived F(2:3) lines indicated that D57 carries two dominant powdery mildew resistance genes. Based on mapping information of polymorphic markers identified by bulk segregant analysis, these two genes were assigned to chromosomes 5DS and 6DS. Using the F(2:3) lines that segregated in a single-gene mode, closely linked PCR-based markers were identified for both genes, and their chromosome assignments were confirmed through linkage mapping. The gene on chromosome 5DS was flanked by Xgwm205 and Xmag6176, with a genetic distance of 8.3 cM and 2.8 cM, respectively. This gene was 3.3 cM from a locus mapped by the STS marker MAG6137, converted from the RFLP marker BCD1871, which was 3.5 cM from Pm2. An evaluation with 15 pathogen isolates indicated that this gene and Pm2 were similar in their resistance spectra. The gene on chromosome 6DS was flanked by co-segregating Xcfd80 and Xmag6139 on one side and Xmag6140 on the other, with a genetic distance of 0.7 cM and 2.7 cM, respectively. This is the first powdery mildew resistance gene identified on chromosome 6DS, and plants that carried this gene were highly resistant to all of the 15 tested pathogen isolates. This gene was designated Pm45. The new resistance gene in D57 could easily be transferred to elite cultivars due to its common wheat origin and the availability of closely linked molecular markers.     

Pm50: a new powdery mildew resistance gene in common wheat derived from cultivated emmer

Fungal diseases of wheat, including powdery mildew, cause significant crop, yield and quality losses throughout the world. Knowledge of the genetic basis of powdery mildew resistance will greatly support future efforts to develop and cultivate resistant cultivars. Studies were conducted on cultivated emmer-derived wheat line K2 to identify genes involved in powdery mildew resistance at the seedling and adult plant growth stages using a BC₁ doubled haploid population derived from a cross between K2 and susceptible cultivar Audace. A single gene was located distal to microsatellite marker Xgwm294 on the long arm of chromosome 2A. Quantitative trait loci (QTL) analysis indicated that the gene was also effective at the adult plant stage, explaining up to 79.0 % of the variation in the progeny. Comparison of genetic maps indicated that the resistance gene in K2 was different from Pm4, the only other formally named resistance gene located on chromosome 2AL, and PmHNK54, a gene derived from Chinese germplasm. The new gene was designated Pm50.     

Transfer and mapping of a gene conferring later-growth-stage powdery mildew resistance in a tetraploid wheat accession

Wheat powdery mildew is a severe foliar disease and causes significant yield losses in epidemic years. Breeding and using resistant cultivars is the most widely employed strategy to curb this disease. To identify and transfer powdery mildew resistance genes in wild emmer wheat accession TA1410 into common wheat, a resistant F3 line derived from the cross of TA1410 × durum wheat line Zhongyin1320 was crossed with common wheat cultivar Yangmai158. The homozygous resistant BC5F2 lines derived from the backcross with Yangmai158 exhibited susceptibility at seedling stage and conferred increasing resistance when the plants were closer to heading stage. In two segregating BC5F3 families investigated at heading stage, the segregation of the resistance fit a 3:1 ratio, suggesting that a single dominant gene controls the resistance. This resistance gene, designated HSM1, was mapped to the 0.6-cM Xmag5825.1–Xgwm344 interval on chromosome 7AL and co-segregated with Xrga-C3 and Xrga-C6. A mapping position comparison with other powdery mildew resistance genes on this chromosome suggested that HSM1 belongs to the Pm1 resistance gene cluster. HSM1 is a useful candidate gene for resistance breeding, particularly in winter-wheat growing areas.