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抗白粉病小偃麦衍生品系高分子量麦谷蛋白亚基分析张晓军;畅志坚;阎晓涛;李欣;詹海仙【摘要】High-molecular-weight glutenin subunit compositions of 64 wheat varieties powdery mildew resistance that derived from Octoploed Trititrigia were identified and analysed through SDS-PAGE technology. Studies showed that there were extremely plentiful HMW-GS types in these tested materials. 3, 5 and 2 kinds of subunit types were tested at Glu-A 1, Glu-B1 and Glu-D1 loci respectively. The majority of varieties have null-subunit at Glu-A1 loci among them, which accounts for 90% at this loci; Variation types are the most plentiful at Glu-B1 loci, the frequency of 7 + 8-subunit is the highest, which is 50%; The frequency of inferior 2 + 12-subunit is the highest, which is 78%; The frequency of superior 5 + 10-subunit that was known wildly is 22%. Therefore the wheat varieties that powdery mildew resistance derived from Octoploed Trititrigia are used to invent new germplasm to offer good parents for crop heredity breeding.%采用聚丙烯酰胺电泳技术(SDS-PAGE)分析了64个抗白粉病八倍体小偃麦衍生品系的高分子量麦谷蛋白亚基( HMW-GS)组成.结果表明,在供试材料中亚基组成类型极其丰富.在Glu-A1,Glu-B1和Glu-D1这3个位点上分别检测到3,5,2种不同的亚基组成类型.其中,在Glu-A1位点上大多数品种都具有null亚基,占该位点亚基的90％；在Glu-B1位点上的变异类型最丰富,7+8亚基出现频率最高,为50％；在Glu-D1位点上,劣质亚基2+12出现的频率最高,为78％,被世界公认的优质亚基5+10出现的频率为22％.这些抗白粉病小麦种质可为育种工作者提供优点突出而无突出缺点的亲本.【期刊名称】《山西农业科学》【年(卷),期】2012(040)010【总页数】3页(P1023-1025)【关键词】高分子量麦谷蛋白亚基;聚丙烯酰胺;抗白粉病;衍生品系【作者】张晓军;畅志坚;阎晓涛;李欣;詹海仙【作者单位】山西省农业科学院作物科学研究所,山西太原030032;山西省农业科学院作物科学研究所,山西太原030032;山西省农业科学院作物科学研究所,山西太原030032;山西省农业科学院作物科学研究所,山西太原030032;山西省农业科学院作物科学研究所,山西太原030032【正文语种】中文【中图分类】S512.903.4小麦白粉病是小麦生产上严重发生的病害，几乎遍布世界各地的小麦产区，是我国麦区的主发病害之一。
2001年3月河南农业大学学报Mar.2001第35卷第1期Journai of Henan Agricuiturai UniversityVoi !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.35No.1收稿日期：2000-07-19基金项目：河南省自然科学基金资助项目（004012100）作者简介：刘红彦（1964-），男，河南嵩县人，河南省农科院副研究员，博士，主要从事分子生物学研究.文章编号：1000-2340（2001）01-0026-06小麦抗白粉病基因的分子标记及标记辅助育种研究进展刘红彦，何文兰，杨共强，宋玉立（河南省农科院植物保护研究所，河南郑州450002）摘要：介绍了DNA 分子标记的主要种类及优缺点，综述了该项技术在小麦抗白粉病基因分子标记中的鉴定、基因定位、遗传图谱的构建，以及作为辅助选择手段在小麦抗白粉病育种中的应用进展.并分析了存在的问题及解决途径.关键词：小麦白粉病；抗病基因；分子标记；标记辅助育种中图分类号：S512.1文献标识码：AAdvances in research on molecular markers linked with genesfor resistance to powdery mildew and applicationto wheat marker-assisted breedingLIU Hong-yan ，HE Wen-ian ，YANG Gong-giang ，SONG Yu-ii（Institute of Piant Protection ，Henan Academy of Agricuiturai Sciences ，Zhengzhou 450002，China ）Abstract ：An introduction is given of the major DNA moiecuiar marker technigues and advances in appiication to theidentification of moiecuiar markers iinked with genes for resistance to powdery miidew in wheat ，gene iocation ，genetic map construction and wheat marker-assisted breeding for resistance to powdery miidew.The existing probiems and their soiutions are anaiyzed.Key words ：wheat powdery miidew ；resistance gene ；moiecuiar marker ；marker-assisted breeding由专性寄生菌Blumeria graminis f.sp.tritici 引起的小麦白粉病是世界性病害.该病害在我国的发生也很普遍，尤以黄淮麦区发生危害最重.长期以来，抗病品种的选育和推广应用是控制白粉病危害的基本措施，但由于抗病基因利用的单一化和病菌毒性变异快，导致推广品种的抗性不断被新的毒性基因所克服，因而合理布局抗病基因，特别是选育具有多个抗病基因组合的持久抗性品种，有效控制小麦白粉病的危害，已成为共识.常规育种导入抗病基因成功与否，多是通过人工接菌来鉴定，这对于导入单个抗病基因是很有效的，但存在鉴定周期长、受环境条件影响大、操作繁琐等缺点，特别是导入多个抗病基因时，由于受鉴别小种的限制和基因间的掩盖，不能准确鉴定导入的是哪一个抗病基因及抗病基因的数量，导致选择过程中抗病基因丢失，难以达到预定育种目标.90年代以来，DNA 分子标记技术的发展完善，为解决这一难题开辟了一条途径.DNA 分子标记具有多态性很高，数量极大，显性或共显性遗传，检测方便、快捷、准确等特点，因而在农作物抗病遗传和育种领域得到广泛的应用［1，2］.作者介绍了近10a 来DNA 分子标记技术在小麦抗白粉病基因分子标记鉴定、遗传作图及标记辅助育种等方面的研究进展.1小麦抗白粉病基因的DNA 分子标记种类在小麦抗白粉病基因分子标记研究中，常用的DNA 分子标记有RFLPs （Restriction Fragment Length Poiy-morphisms ，限制性片段长度多态性）、RAPDs（Random Ampiified Poiymorphic DNAs ，随机扩增多态性DNA ）、第1期刘红彦等：小麦抗白粉病基因的分子标记及标记辅助育种研究进展27AFLPs（Ampiified Fragment Length Poiymorphisms，扩增片段长度多态性）、SSR（Simpie Seguence Repeats，简单序分离群体、双单倍体列重复）等.鉴定标记所用的材料为近等基因系［3］（Near-isogenic iines，NIL）和由F2（Doubie hapioid，DH）或重组近交系（Recombinant reiated inbred iines，RIL）构建的DNA抗感池［4］.1.1RFLP标记RFLP技术是利用限制性内切酶，酶切不同生物个体基因组DNA，琼脂糖电泳后，转膜、变性处理，然后用一组放射性同位素（通常是32P）或非放射性物质（如地高辛、生物素等）标记的探针（常用随机的基因组克隆或cDNA克隆作探针）进行分子杂交，再通过放射自显影（或非同位素技术）观察酶切片段长度的差异.HARTL等最早于1993年以NIL为材料，用RFLP技术找到了1个与小麦抗白粉病基因Pm3b紧密连锁的RFLP标记［5］，此后又有学者陆续找到与Pm1，Pm2，Pm3b，Pm4a，Pm5，Pm6，Pm12，Pm13和Pm18连锁的RFLP标记［6~12］，对这些基因进行了更精确的定位.有些RFLP标记可转化成PCR标记—STS（Seguence tag-ging site），便于应用.1.2RAPD标记RFLP因技术复杂，使用放射性同位素，其普及应用受到限制.近几年，RAPD技术因具有操作简单，周期短，自动化程度高，不用同位素等优点，而得到广泛应用.该技术是采用一套随机核苷酸序列（通常为10个碱基）为引物，扩增基因组DNA，产生随机长度的DNA片断，获得的一种DNA标记，即RAPD标记［13］.该标记可经克隆测序、设计特异引物，转化为SCAR（Seguenced Characterized Ampiified Regions）标记.HARTL等利用F分离群体构建的DNA池进行RAPD分析，鉴定到1个与Trigo BR34中的未知抗白粉病基因连锁距2离为13cM的RAPD标记［8］.随后其他学者又鉴定出与Pm1，Pm2，Pm4a，Pm21和Pm25连锁的RAPD标记［14~19］.其中与Pm1和Pm21连锁的标记已转化为SCAR标记［14，18］.1.3AFLP标记AFLPs是荷兰科学家ZABEAU等1993年发明的一种DNA分子标记新技术，其基本原理是选择性扩增基因组DNA的限制性酶切片段，其方法是用限制性内切酶酶切基因组DNA，将特定的接头（adapter）与酶切的DNA片段连接，形成带接头的特异片段，通过接头序列和PCR引物的识别，特异性片段得到扩增，最后通过PAGE观察酶切片段的多态性［20］.可见AFLP实际上是一种RFLP和RAPD相结合的技术，既有RFLPs的可靠性，也有RAPDs的灵敏性.它的最大优点是多态性丰富，重复性好，通过变性PAGE可检测到的谱带多达50~100条，是一种十分理想和有效的遗传标记，能用于构建高清晰度的遗传图谱［21］.缺点是成本高，通常需要用同位素检测，也可以经硝酸银染色观察多态性.HARTL等利用AFLP技术对Rm4b进行分子作图，6个AFLP标记在染色体上的覆盖范围小于13cM［22］.1.4SSR标记SSR是基因组重复序列中的一种类型，又称微卫星DNA（Microsateiiite DNA）.重复单位很短，只有1~5bp，总长度为几十个bp，分布于整个基因组的不同位置上［23，24］.微卫星DNA两端的序列一般是相对保守的单拷贝序列，据此可通过设计特异引物进行SSR-PCR扩增来揭示微卫星DNA的多态性.其特点是多态性强，随机均匀地分布于整个基因组，可通过PCR快速检测分析，引物序列公开发表后，便能广泛交流使用.2DNA分子标记的应用2.1小麦抗白粉病基因分子标记的鉴定、基因定位和遗传图谱的构建截止目前，在已报道的37个小麦抗白粉病基因中［8，25，26，27］，有16个基因位点鉴定出不同类型的DNA 分子标记，并进行了分子作图.例如，用6个AFLP标记构建了含有Pm4b的部分连锁图［22］.利用RFLP标记，将Pm12定位于易位染色体6BS-6SS.6SL的短臂上，并构建了部分遗传图谱［11］.但尚有21个基因没有标记（见表1）.在进行分子标记鉴定、基因定位和遗传作图时，可以2种以上技术结合使用.KELLER等利用176个RFLP探针和9个小麦微卫星标记构建了包含23个连锁群（2469cM）、182个位点的遗传图谱，通过复合区间作图，检测到控制成株期白粉病抗性的18个OTL（guantitative trait ioci），解释77%的表型变异.2个主效OTL中，1个OTL来自Forno，位于7B上，认为代表已知的Pm5基因，另1个位于5A，来自斯卑尔脱小麦Oberkuimer，不同于任何已知Pm基因［25］.28河南农业大学学报第35卷表l小麦抗白粉病基因及与其连锁的分子标记基因名称位点来源代表品种标记名称连锁距离/cM参考文献Pmla7AL普通小麦Axminster Xcdo3470［6］Xwhsl78 2.812.7［8］UBC3204200［l4］UBC638550!SCAR5500［l4］OPFl2650 5.41l.9［l4］Pmlb7A栽培—粒小麦MocziatkaPmlc7A栽培—粒小麦MlNPmld7A斯卑尔脱小麦TRI2258Pm25DS普通小麦Maris Huntsman Xbcdl87l 3.5［6］Xwhs295 2.712.6［8］Xwhs350［8］Xfba393［7］OPI04l700l2.213.3［l5］Pm3a lAS普通小麦Asosan Xbcdl434［6］Xwhsl79［5］Pm3b lA普通小麦Chui Xbcdl434l.3［6］Xwhsl79 3.31l.9［5］Pm3c lA普通小麦SonoraPm3d lA普通小麦KoiibriPm3e lA普通小麦Wl50Pm3f lA普通小麦Michigan Amber/8"CcPm4a2AL栽培二粒小麦Khapii/8"Cc Xbcdl23l-2A（2）!STS l7000［6］［28］Xcdo678-2A0［6］Xbcdl23l-2A（l）l.5［6］Xbcd292-2A l.5［6］Pm4b2AL波斯小麦Amarda Sl6Ml2/3l5［22］Sl6Ml5/l59Sl5M23/200S2lM23/323Sl9M23/l33Sl7M20/l33Pm57BL栽培二粒小麦Hope Xgik750［9］Xpsr547Xpsrl29OTL7BL Forno Xgik7500.7［25］Xgwmllla 3.7Xpsr547 5.4Xpsrl29ll.4Pm62B提莫菲维小麦Timaien Xbcdl35ecoR!9kb l.61l.5［l0］Xbcd307ecoR"8.8kb l.61l.5［l0］Xbcd266ecoR!l8kb 4.812.6［l0］Pm74BS黑麦TransecPm8lB黑麦KavkazPm97AL普通小麦NormandiePml0lD普通小麦Norin4Pmll6BS普通小麦中国春Pml26BS拟斯卑尔脱山羊草Line3l Xpsr55l，Xpsrl0，［ll］Xpsrl06，Nor2，Xpsrl4l，Xpsrll3Pml33D高大山羊草RlA Xutvl4［l2］Pml46B普通小麦AkabozuPml57DS普通小麦Norin4Pml64A野生二粒小麦Norman iinesPml7lA黑麦AmigoPml8普通小麦Weihenstephan MlN Xwhsl78 4.413.6［8］第1期刘红彦等：小麦抗白粉病基因的分子标记及标记辅助育种研究进展29续表1小麦抗白粉病基因及与其连锁的分子标记基因名称位点来源代表品种标记名称连锁距离/cM参考文献Pm普通小麦Trigo BR34OPH11190013Pm197D方穗山羊草Syntheticxx186Pm206BL黑麦KS93WGRC28Pm217AS簇毛麦扬麦5/sub.6V OPH1719000［17］OPH171400!SCAR12650［18］SCAR1400Pm221D普通小麦VirestPm235A普通小麦Line81-7241Pm246D普通小麦ChiyacaoPm251A栽培一粒小麦NC96BGTA5OPAG0495017.214.48［19］OPX06105012.813.96［19］OPAI1460021.614.88［19］OTL5A Oberkuimer Xpsr644a 1.1［25］APR（成株期抗性）普通小麦Massey Xwms304Xwms294Xwg996Xksu D2217.912.39.27.7［27］注：APR的连锁距离用重组率（%）表示.!"!抗白粉病基因的分子检测和标记辅助育种分子标记用于抗病基因检测，不受环境、生长季节限制，周期短.在育种过程中，用作辅助选择手段，可以提高选择的准确性，缩小育种群体，结合加代技术，能大大缩短育种年限，提高育种效率.刘金元等利用国外筛选到的与抗白粉病基因Pm2及Pm4a紧密连锁的RFLP标记，分析国内育成的小麦抗白粉病材料，发现即使在不同的遗传背景下，这些RFLP标记仍可用于对Pm2及Pm4a的鉴定［29］.RFLP标记的突出优点是重复性好，稳定可靠，但技术复杂，成本高，使用同位素，在小麦育种实践中要检测大量群体，这是不现实的，需要转化为方便易用的STS标记.RAPD标记虽检测方便，但稳定性差，所以应通过克隆测序转化为SCAR标记，以提高检测的稳定性和实用性.Mohier等转化成的STS标记，检测Pm2的有无［30］.刘金元等将Pm4a的共分离RFLP标记Xbcd1231-2A转化为STS标记，在11个已知含有Pm4a基因的小材料中均扩增出此标记，而在不含有Pm4a的小麦材料中未扩增出此标记，初步认为该标记可用于Pm4a基因的跟踪检测［28］.Pm21来自簇毛麦的抗白粉病基因，抗目前已知所有生理小种，具有重要的应用价值，刘志勇等将与其连锁的RAPD标记OPH171400转化为SCAR1265和SCAR1400，用于“滚动式加代回交转育”中Pm21的检测，现已获得许多具有不同遗传背景、农艺性状优良的抗白粉病品系［18］.利用不同基因的分子标记，已成功地将Pm2+Pm4a，Pm2+Pm21和Pm4a+Pm21基因组合导入感病品种扬158［31］.河南是小麦种植大省，白粉病常年都有发生，而当前推广的品种绝大多数是感病品种，因此作者着手利用现有的分子标记，开展标记辅助育种工作，将Pm2，Pm4a，Pm21等抗病基因导入豫麦13、豫麦18和豫麦49等感病品种，争取在短期内选育出高产抗病品种.#存在的问题及解决途径1）目前鉴定到的标记大多数为RFLP标记，实用性差，应尽快将连锁程度高的RFLP标记，转化为STS 标记，便于在小麦抗病育种实践中应用.2）标记数量少，完全连锁的标记少，互斥相标记少，影响基因检测的准确性.因此应增加紧密连锁标记的数量，特别是互斥相标记和共显性标记.同时采用多个标记，才能准确检测基因，提高间接选择效率.3）已完成的分子标记鉴定工作主要集中在Pm2，Pm4a，Pm6和Pm21等几个抗性比较好的基因上，其它抗性好的基因如Pm16，Pm17，Pm20和Pm24等尚没有标记，而且忽视了对一些小种已丧失抗性的基因，如Pm3，Pm5，Pm7，Pm8，Pm9等.这些抗性差的基因虽无法单独利用，但可以与其它抗性较好的基因组合使用，拓宽抗性谱，这种基因组合在其它作物上已有成功的例子.在检测这些基因时，分子标记将起重要作30河南农业大学学报第35卷用.所以，从多基因布局和综合利用角度考虑，抗性差的基因，仍需要鉴定其分子标记.综上所述，完成所有小麦抗白粉病基因分子标记的鉴定，构建具有众多完全连锁的、不同连锁相的及共显性的分子标记体系，对于大量品种资源系统开展抗白粉病基因的分子检测，及通过分子标记辅助选择手段选育持久抗病品种，实现小麦白粉病的长期有效控制及小麦生产的可持续发展，具有长远、重要的经济意义.参考文献：［1］GLICK B R，THOMPSON J E.Methods in piant moiecuiar bioiogy and biotechnoiogy［M］.CRC Press Inc Boca Raton，1993.［2］KAWCHUK L M，HACHEY J，LYNCH D R.Deveiopment of seguence characterized DNA markers iinked to a dominant verticiiiium wiit resistance gene in tomato［J］.Genome，1998，41：91-95.［3］YOUNG N D，ZAMIR D，GANAL M W，et e of isogenic iines and simuitaneous probing to identify DNA markers tightiy iinked to Tm-2a gene in tomato［J］.Genetics，1988，120：579-585.［4］MICHELMORE R W，PARAN 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in wheat ［J］.Theor Appi Genet，1997，94（6/7）：832-840.［15］刘金元，陶文静，刘大钧，等.与小麦抗白粉病基因Pm2紧密连锁RAPD标记的筛选研究［J］.遗传学报，2000，27（2）：139 -145.［16］李松涛，张忠延，王斌，等.用新的分子标记方法（RAPD）分析小麦抗白粉基因Pm4a的近等基因系［J］.遗传学报，1995，22（2）：103-108.［17］OILL，CAO M S，CHEN P D，et ai.Identification，mapping and appiication of poiymorphic DNA associated with resistance gene Pm21 of wheat［J］.Genome，1996，392：191-197.［18］刘志勇，孙其信，李洪杰，等.小麦抗白粉基因Pm21的分子标记鉴定和标记辅助选择［J］.遗传学报，1999，26（6）：673-682.［19］SHI A N.LEATHS，MURPHY J P.A major gene for powdery miidew resistance transferred to common wheat from wiid einkorn wheat ［J］.Phytopathoiogy，1998，88：144-147.［20］VOS P，HOGERS R，BLEEKER M，et ai.AFLP：a new technigue for DNA fingerprinting［J］.Nucieic Acids Res，1995，23：4407-4414.［21］MEKSEM K，LEISTER D，PELEMAN J.A high-resoiution map of the vicinity of the R1iocus on chromosome of potato based on RFLP第1期刘红彦等：小麦抗白粉病基因的分子标记及标记辅助育种研究进展31and AFLP markers［J］.Moi Gen Genet，1995，249：74-81.［22］SLINKARD A E.Proc9th Int wheat Genet Symp［C］.Sakatoon：Univ Extension 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长穗偃麦草7E遗传图谱构建及小麦抗赤霉病和叶锈病基因定位的开题报告一、研究背景长穗偃麦草（Leymus mollis）是一种优良的牧草，具有高产、优质、抗逆性强等特点，已广泛应用于草地建设及畜牧业生产。
近年来，随着分子生物学和遗传学技术的发展，长穗偃麦草的遗传图谱研究也逐渐成为了研究的热点。
另一方面，小麦是我国主要的粮食作物之一，但在种植过程中常常受到多种病害的侵害，其中赤霉病和叶锈病是较为常见的病害。
因此，寻找小麦抗病基因，提高小麦的抗病能力，对保障我国粮食安全具有十分重要的意义。
目前，许多研究表明，长穗偃麦草作为小麦的近缘种，与小麦在基因组结构上有很高的一致性，因此利用长穗偃麦草的遗传图谱寻找小麦抗病基因是非常有前景的研究方向。
二、研究内容本研究将利用长穗偃麦草7E染色体为基础，构建长穗偃麦草全基因组遗传图谱，并利用该图谱开展小麦抗赤霉病和叶锈病基因定位研究。
具体研究内容如下：1. 长穗偃麦草全基因组DNA提取和测序，构建其遗传图谱。
2. 利用已知的分子标记、SRAP、SSR、SNP等技术，对长穗偃麦草遗传图谱进行分析，获得其基因物理位置、遗传距离等信息。
3. 利用该图谱与小麦基因组结构的一致性，将已知的赤霉病和叶锈病抗性基因相关序列比对筛选，筛选出与小麦抗病基因相关的长穗偃麦草基因序列。
4. 基于长穗偃麦草的遗传图谱和小麦-长穗偃麦草基因组相似性比对的结果，结合小麦近缘种的其他遗传图谱和丰富的小麦育种资源，开展小麦抗赤霉病和叶锈病基因的定位和克隆，最终鉴定小麦抗病基因。
三、研究意义本研究的开展具有以下重要意义：1. 构建长穗偃麦草遗传图谱，对长穗偃麦草遗传学和基因组学研究具有重要的推动作用。
2. 利用长穗偃麦草遗传图谱，开展小麦抗赤霉病和叶锈病基因定位，将丰富的小麦育种资源与现代分子生物学技术相结合，加快了小麦抗病基因的研究进度。
3. 研究结果为小麦育种和农业生产提供了重要的理论支持和实验依据。
小麦品系CH7034中耐盐QTL定位张潇文;李世姣;张晓军;李欣;杨足君;张树伟;陈芳;常利芳;郭慧娟;畅志坚;乔麟轶【期刊名称】《作物学报》【年(卷),期】2022(48)10【摘要】鉴定小麦耐盐种质对于充分利用盐碱地和保障粮食安全具有重要意义。
CH7034是本实验室自育的1份小麦耐盐品系,为了明确其耐盐性遗传规律和控制位点,利用CH7034与盐敏感品种SY95-71的重组自交系群体进行QTL分析。
基于SNP芯片数据和盐害指数(salt injury index),在2A、2D、4B和5A染色体上共检测出6个QTL,分别为QSI.sxau_2A、QSI.sxau_2D、QSI.sxau_4B.1、QSI.sxau_4B.2、QSI.sxau_5A.1和QSI.sxau_5A.2。
其中,QSI.sxau_5A.1在3次盐胁迫试验中均能被检测到,具有最高的表型变异解释率(15.73%~20.18%),且不同于5AL染色体上已报道的其他耐盐位点。
在QSI.sxau_5A.1区间开发并整合了7个SSR标记,将LOD峰值进一步确定在SSR-D1处。
基于转录组数据库,从QSI.sxau_5A.1区段内筛选了12个响应盐胁迫的高置信基因。
研究结果为CH7034耐盐位点的精细定位乃至克隆奠定了基础,也为小麦耐盐品种选育提供了新种质和分子标记。
【总页数】9页(P2654-2662)【作者】张潇文;李世姣;张晓军;李欣;杨足君;张树伟;陈芳;常利芳;郭慧娟;畅志坚;乔麟轶【作者单位】山西大学生命科学学院;山西农业大学农学院/作物遗传与分子改良山西省重点实验室/省部共建有机旱作农业国家重点实验室(筹);电子科技大学生命科学与技术学院【正文语种】中文【中图分类】S51【相关文献】1.新疆耐盐冬小麦新品系耐盐特性的研究2.波兰小麦品系XN555×普通小麦品系中13衍生重组自交系(RILs)群体中籽粒品质相关性状QTL定位3.用微卫星标记定位小麦耐盐突变体的耐盐相关基因4.源于长穗偃麦草的小麦新品系CH7034抗白粉病基因的染色体定位5.波兰小麦×普通小麦品系“中13”RIL群体籽粒特性的QTL定位因版权原因，仅展示原文概要，查看原文内容请购买。
作物学报 ACTA AGRONOMICA SINICA 2008, 34(2): 212−216/zwxb/ ISSN 0496-3490; CODEN TSHPA9E-mail: xbzw@基金项目: 国家重点基础研究发展计划(973计划)项目(2005CCA01600); 国家自然科学基金项目(30170602); 河北农业大学校青年基金项目(QN200503)作者简介: 张娜(1979−), 女, 博士研究生, 研究方向：分子植物病理学。
E-mail: zhangna110@*通讯作者(Corresponding author): 刘大群(1958−), 男, 博士生导师, 从事植物病害生物防治和分子植物病理学研究。
E-mail: ldq@; 杨文香(1966−), 女, 博士生导师, 从事植物病害生物防治和分子植物病理学研究。
E-mail: wenxiangyang2006@Received(收稿日期): 2007-01-15; Accepted(接受日期): 2007-07-31.DOI: 10.3724/SP.J.1006.2008.00212小麦抗叶锈病基因Lr24的一个新STS 标记张 娜 陈玉婷 李亚宁 张立荣 孟庆芳 张 汀 杨文香* 刘大群*(河北农业大学植物病理系分子植物病理学实验室/河北省农作物病虫害生物防治工程技术研究中心, 河北保定 071001)摘 要: 来源于长穗偃麦草的基因Lr24对小麦叶锈病具有很高的抗性, 本研究旨在开发用于Lr24基因分子标记辅助育种的新的分子标记。
从定位于小麦3D 染色体的22对SSR 、EST-SSR 引物中筛选出4对揭示TcLr24多态性的引物, 用468株F 2抗感群体对这4对引物进一步检测, 得到1个与Lr24共分离的EST-SSR 标记Xcwem17。
对该标记进行测序, 并设计了STS 引物。
用该STS 引物及已知的Lr24 SCAR 引物对试验群体进行验证, 两对引物在该F 2群体中均表现共分离, 且Xcwem17可在TcLr24单基因系和已知含Lr24的农家品种泰山1号中可扩增出180 bp 单一条带, 感病对照及其余7个近等基因系无扩增。
麦类作物学报㊀２０２０,４０(３):封三J o u r n a l o fT r i t i c e a eC r o ps d o i :１０．７６０６/j．i s s n ．１００９Ｇ１０４１．２０２０．０３．１７网络出版时间:２０２０Ｇ０３Ｇ２３网络出版地址:h t t p ://kn s ．c n k i ．n e t /k c m s /d e t a i l /６１．１３５９．S ．２０２００３２０．１４１５．０２８．h t m l 节水高产㊁高抗白粉病小麦新品种 金麦９１９收稿日期:２０１９Ｇ１０Ｇ２１基金项目:国家重点研发计划项目(２０１７Y F D ０１００６００);山西省重点研发计划项目(２０１７０３D ２１１００７,２０１８０３D ４２１０);山西省农科院育种工程项目(１７y z gc ０１０)第一作者E Ｇm a i l :s x n k y z j＠１２６．c o m 通讯作者:郑兴卫(E Ｇm a i l :s m i l e z x w＠１２６．c o m )郑军１,赵佳佳１,葛川２,郑兴卫１,乔玲１,乔麟轶３,张树伟３,杨三维１,撖晓东３(１．山西省农业科学院小麦研究所,山西临汾０４１０００;２．山西省山西科技情报研究所,山西太原０３００００;３．山西省农业科学院作物科学研究所,山西太原０３００００)㊀㊀金麦９１９(参试代号临４１３３)系山西省农业科学院小麦研究所在当前水资源紧缺需求下选育出的节水高产㊁高抗白粉病小麦新品种.以邯郸６１７２为母本,C H ７０３４为父本(C H ７０３４为自育品系,亲本为偃麦草与晋麦６３杂交选育的隐形易位系,具有综合抗性好㊁穗粒数多㊁根系发达等优点)进行有性杂交,回交１次,采用系谱法经过多年水旱轮回选择和分子标记辅助选择;在节水指数(W S I )大于１．０的株系中筛选含有矮秆基因(R h t ２,R h t ８)和优质高分子量麦谷蛋白亚基(G l u Ｇ１).２０１８年１２月通过山西省农作物品种审定委员会审定,审定编号为晋审麦２０１８０００８.１㊀生物学特性金麦９１９属半冬性㊁中熟大穗型品种,全生育期２４０d 左右,幼苗半匍匐,芽鞘为绿色.株型半紧凑,株高８０c m ,叶片浅绿色㊁无蜡质,穗型为长方型,穗色为黄白色,穗长１０c m ,长芒,白芒,白壳;卵形护颖,斜肩,颖嘴中弯,小穗密度中等;椭圆粒,白粒,硬质,较饱;一般穗数５４０ˑ１０４,穗粒数３９个,千粒重４０g ,穗层整齐.耐旱,根系下扎较深,后期根系活力强,抗干热风,耐后期高温,节水指数(W S I )为１．１３,具有较强的抗旱性.２㊀产量表现２０１６－２０１７年度参加山西省南部中熟旱地组品种区试,８个试验点全部增产,平均产量５０３８．５k gh m －２,比对照晋麦４７增产１１％,居参试品种第二名;２０１７－２０１８年度续试并生产试验,８个试验点全部增产,区试平均产量４７６４．０k gh m －２,比晋麦４７增产７．２％;生产试验平均产量４７２２．０k g h m －２,比晋麦４７增产７．３％.突出特点是抗旱节水,适应性和稳产性好,在浇１水的正常年份产量可达６０００~７５００k gh m －２.３㊀抗病性经山西省农科院植保所２０１６－２０１７和２０１７－２０１８两个年度的温室及大田接种鉴定,金麦９１９苗期对混合菌表现为中感条锈病㊁中感叶锈病和中抗白粉病,成株期田间表现为中抗条锈病㊁中抗叶锈病和高抗白粉病.４㊀品质金麦９１９含高分子量麦谷蛋白１㊁１４＋１５㊁２＋１２;其中G l u ＧA １和G l u ＧB １为优质亚基.２０１７年农业部谷物及制品质量监督检验测试中心(哈尔滨)进行品质分析,金麦９１９籽粒容重７９２gL －１,蛋白质含量１５．７２％,湿面筋含量３７．２％,吸水量６１．２m L １００g－１,面团形成时间４．５m i n ,稳定时间２．８m i n ,弱化度１３１F ．U .５㊀栽培技术要点金麦９１９抗冻和抗旱性较强,抗青干能力强,成熟落黄好,适播期为１０月上旬,基本苗２６０万~２８０万株 h m －２,晚播应适当增加播量.适宜于山西省南部及相似生态区的雨养旱地和扩浇地种植.有条件地区春季在拔节期结合浇水追施尿素１次,雨养地区一般在起身期至拔节期结合降雨追施;高水肥条件下注意防治倒伏.其余栽培技术要点同当地大田生产相同.。
小麦-中间偃麦草隐形渗入系抗白粉病基因pmCH83分子定位孙翠花;侯丽媛;郭慧娟;张晓军;贾举庆;李欣;詹海仙;畅志坚【摘要】小麦新种质CH09W83为八倍体小偃麦TAI7047与高感小麦品种晋太170杂交、回交后代衍生而来的高代选系,在苗期免疫或高抗我国白粉病菌株E09、E20、E21、E23、E26、Bg1和Bg2.为定位CH09W83中的抗病基因,将CH09W83与感病亲本杂交和回交,通过对F1、F2、F2:3和BC1代的接种鉴定和遗传分析,证实CH09W83成株期对E09的抗性由1对隐性核基因控制,暂命名为pnCH83.采用分离群体分组分析法(bulked segregant analysis,BSA),以658对SSR标记对台长29(感病)×CH09W83的F2群体分析发现,抗性基因pnCH83与SSR标记Xgpw 7272、Xwmc62、Xgwm251、Xgwm193连锁,与两翼邻近标记Xwmc652和Xgwm251的遗传距离分另为3.8 cM和4.3 cM.利用中国春缺体四体、双端体将pmCH83及其连锁标记定位在4BL染色体上.原位杂交、染色体配对及连锁标记分析结果表明,CH09W83可能是一个小麦与中间偃麦草的隐形异源渗入系.系谱和图谱位置分析表明,pmCH83很可能是来自中间偃麦草一个新的抗白粉病基因.【期刊名称】《作物学报》【年(卷),期】2013(039)012【总页数】8页(P2107-2114)【关键词】隐形异源渗入;白粉病抗性;连锁图谱;分子标记;GISH【作者】孙翠花;侯丽媛;郭慧娟;张晓军;贾举庆;李欣;詹海仙;畅志坚【作者单位】山西大学研究生院,山西太原030006;山西大学研究生院,山西太原030006;山西省农业科学院作物科学研究所/农业部黄土高原作物基因资源与种质创制重点实验室,山西太原030031;山西省农业科学院作物科学研究所/农业部黄土高原作物基因资源与种质创制重点实验室,山西太原030031;山西农业大学农学院,山西太谷030801;山西省农业科学院作物科学研究所/农业部黄土高原作物基因资源与种质创制重点实验室,山西太原030031;山西省农业科学院作物科学研究所/农业部黄土高原作物基因资源与种质创制重点实验室,山西太原030031;山西省农业科学院作物科学研究所/农业部黄土高原作物基因资源与种质创制重点实验室,山西太原030031【正文语种】中文由Blumeria graminisf. sp.tritici(Bgt)引起的小麦白粉病是世界各小麦产区的主要病害之一, 随着小麦品种矮化、种植密度加大和生产条件的改善,小麦白粉病危害日趋严重。
小麦白粉病抗性基因的来源及染色体定位1 小麦白粉病的抗性基因的来源1930年澳大利亚学者Waterhouse首次报道小麦品种Thew携带一个显性抗白粉病基因，以后对小麦白粉病基因的抗性表现及遗传特点的研究有了较大的进展。
小麦白粉病抗性基因主要来自普通小麦本身及其近缘种属：来源于普通小麦的抗病基因包括 Pm1(a-c)、Pm3(a-j)、Pm5e、Pm9、Pm10、Pm11、Pm14、Pm15、Pm18（=Pm1c）、Pm22、Pm23、Pm24、Pm28、Pm29。
来源于小麦近缘种的抗病基因包括Pm1d（斯卑尔脱小麦, Triticum spelta），Pm5(a-d)（栽培二粒小麦, Triticum dicoccum S.），Pm4b（波斯小麦, T. carthlicum Nevski），Pm25（野生一粒小麦, Triticum boeoticum B oiss），Pm16、Pm26、Pm30、Pm31和Pm36（野生二粒小麦, Triticum dicoccoides Korn[3][4][5][6]），Pm6、Pm27和Pm37（提莫菲维小麦, T.timopheevii zhuk.），Pm38（硬粒小麦，Triticum durum Desf）。
来源于小麦近缘属的包括Pm7、Pm8、Pm17和Pm20（黑麦, Secale cereale），Pm12、Pm32（拟斯卑尔脱山羊草,Triticum speltoides），Pm13（高大山羊草, Ae. Iongissimum)，Pm21（簇毛麦，Dasypyrum villosum)，Pm33（小伞山羊草, Aegilops umbellulata），Pm2、Pm19、Pm34和Pm35（粗山羊草, Aegilops tauschii）。
其中，Pm10、Pm11、Pm14和Pm15只抗偃麦草专化型白粉病，而不抗小麦白粉病。
除已定名的Pm基因外，还发现了一些尚不明确的抗白粉病基因，如Bennet（1984）发现Mld来自硬粒小麦（Triticum durum Desf）。
ResearchCrop Genetics and Breeding—PerspectiveThe Potential Role of Powdery Mildew-Resistance Gene Pm40in Chinese Wheat-Breeding Programs in the Post-Pm21EraShengwen Tang a ,Yuting Hu a ,Shengfu Zhong a ,Peigao Luo a ,b ,⇑a Sichuan Provincial Key Laboratory of Plant Breeding and Genetics,Sichuan Agricultural University,Chengdu 611130,ChinabState Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing 100193,Chinaa r t i c l e i n f o Article history:Received 8August 2017Revised 3December 2017Accepted 26June 2018Available online 4July 2018Keywords:WheatPowdery mildew Pm21Pm40Alien species Native resistancea b s t r a c tPowdery mildew, which is caused by Blumeria graminis f. sp. tritici (Bgt ), is an important leaf disease that affects wheat yield. Powdery mildew-resistance (Pm ) gene Pm21 was first transferred into wheat in the 1980s, by translocating the Heuchera villosa chromosome arm 6VS to the wheat chromosome arm 6AL (6VS Á6AL). Recently, new Bgt isolates that are virulent to Pm21 have been identified in some wheat fields, indicating that wheat breeders should be aware of the risk of deploying Pm21, although pathological details regarding these virulent isolates still remain to be discovered. Pm40 was identified and mapped on the wheat chromosome arm 7BS from several wheat lines developed from the progenies of a wild cross between wheat and T hinopyrum intermedium . Pm40 offers a broad spectrum of resistance to Bgt , which suggests that it is likely to provide potentially durable resistance. Cytological methods did not detect any large alien chromosomal segment in the wheat lines carrying Pm40. Lines with Pm40 and promising agronomical traits have been released by several wheat-breeding programs in the past several years. Therefore, we believe that Pm40 will play a role in powdery mildew-resistance wheat breeding after Pm21 resistance is overcome by Bgt isolates. In addition, both Pm21 and Pm40 were derived from alien species, suggesting that the resistance genes derived from alien species are potentially more durable or effective than those identified from wheat.Ó 2018 THE AUTHORS. Published by Elsevier LTD on behalf of Chinese Academy of Engineering and Higher Education Press Limited Company. This is an open access article under the CC BY-NC-ND license1.IntroductionWheat powdery mildew,which is caused by Blumeria graminis f.sp.tritici (Bgt ),is a destructive fungal disease around the world,and remains a significant threat to wheat (Triticum aestivum L.(T.aestivum L.))production.In China,wheat powdery mildew has been widespread in most winter wheat-growing regions since the 1970s,and has caused severe yield losses [1].In southwest China,although powdery mildew was second to stripe rust (caused by Puccinia striiformis f.sp.tritici (Pst ))in the past,it now surpasses stripe rust as the most destructive wheat leaf disease due to the deployment of semi-dwarf cultivars and the increased use of irrigation and nitrogenous fertilizers [2–4].Chemical control and appropriate wheat-cultivation measures can reduce some of the yield losses caused by powdery mildew;however,growing new disease-resistant cultivars is the beststrategy for controlling powdery mildew and will also reduce both the production cost and the environmental contamination from the application of fungicides [5].Powdery mildew-resistance (Pm )genes are the prerequisite for developing resistant wheat cul-tivars;therefore,the identification of new Pm genes is an impor-tant ongoing task for breeders in order to improve wheat resistance to powdery mildew.To date,91Pm genes (Pm18=Pm1c ,Pm22=Pm1e ,Pm23=Pm4c ,Pm17=Pm8,Pm31=Pm21,and Pm48=Pm46)[6–12]have been identified on 54loci of wheat chromosomes (Table 1)[1,4,6–10,12–78].Pm genes have been assigned on almost all chromosomes except 3D and 4D.The num-ber of loci on the B genome is up to 27(50.0%)out of 54loci,while the number of loci on the D genome is only 13(24.1%)(Table 2).The number of Pm genes mapped on the A genome is up to 42(46.2%),whereas only 17(18.7%)Pm genes are mapped on the D genome.The mean number of Pm alleles per loci is 3.00,1.19,and 1.31in the A,B,and D genomes,respectively,which shows that each Pm locus in the A genome has more alleles than those in the B and D genome.Moreover,the data in Table 2show that the alien Pm genes such as Pm21and Pm40,usually displaying⇑Corresponding author.E-mail address:lpglab@ (P.Luo).the board-spectrum and putatively durable resistance,were frequently transferred from wild relatives into A and B genome.2.The contribution of alien Pm genes to the improvement of wheat resistance to powdery mildewThe transfer of desirable alien genes from wild relatives with durable resistance to a broad spectrum of pathogens into wheat is an important objective in modern breeding programs[79]. Within the54named Pm genes,44genes in37loci were derived from wild relatives or sparsely cultivated subspecies.These include T.boeoticum(Pm25)[20],T.monococcum(Pm1b and Pm4d)[7,25], T.dicoccoides(Pm16,Pm26,Pm30,and Pm31)[27,29,41,51],T.dicoc-cum(Pm4a,Pm5a,and Pm5b)[59,63,80],T.carthlicum(Pm4b and Pm33)[23],T.turgidum dicoccon(Pm3k,Pm36,Pm41,Pm42,and Pm49)[17,43,44,48,52],T.timopheevi(Pm6,Pm27,and Pm37) [35,39,58],T.urartu(Pm60)[81],A.cristatum(Pm2b)[70],Aegilops spp.(Pm1d,Pm2a,Pm12,Pm13,Pm19,Pm29,Pm32,Pm34,Pm35, Pm53,Pm57,and Pm58)[6,7,38,46,47,53,72,74,75,78,82],Haynaldia villosa(H.villosa,syn.Dasypyrum villosum)(Pm21and Pm55)[28,30],Secale cereale(Pm7,Pm8,Pm17,Pm20,and Pm56) [10,19,49,83],and Thinopyrum spp.(Pm40,Pm43,and Pm51) [45,64,69].Within the44Pm genes derived from alien species or sparsely cultivated subspecies,22are assigned on the B genome, while only14are assigned on the A genome,and eight on the D genome(Table2).The proportion of alien Pm genes within the whole Pm genes is0.69on B genome,while0.33on A genome and0.47on D genome;this large number and proportion of alien genes on the B genome may explain its high tolerance to the presence of alien chromatin.Most of the published alien Pm genes have not been successfully used in breeding in the past;however, several alien Pm genes have played an important role in Chinese wheat breeding.2.1.Alien Pm genes widely used in Chinese wheat breedingPm8,one of the best-known and most widely used genes in wheat breeding,has played a major role in protecting wheat yield loss from powdery mildew infection.Pm8was transferred from the ‘‘Petkus”rye chromosome into hexaploid wheat in the early1930s.Table1Powdery mildew-resistance genes reported in wheat and their chromosomal distribution.Chromosome Locus Genes from T.aestivum Genes from alien species1A Pm3,Pm25Pm3a[13],Pm3b[13],Pm3c[14],Pm3d[15],Pm3e[15],Pm3f[15],Pm3g[16],Pm3h[16],Pm3i[16],Pm3j[16],Pm3l[17],Pm3m[18],Pm3n[18],Pm3o[18],Pm3p[18],Pm3q[18],Pm3r[18]Pm3k(T.turgidum dicoccon)[17],(Secale cereale (S.cereale))[19],Pm25(T.boeoticum)[20]2A Pm4,Pm50Pm4c(Pm23)[9],Pm50[21]Pm4a(T.dicoccum)[14,22],Pm4b(T.carthlicum)[23,24],Pm4d(T.monococcum)[25]3A Pm44Pm44[26]4A Pm16Pm16(T.dicoccoides)[27]5A Pm55Pm55(5AL/5DL)(Dasypyrim villosa)[28]6A Pm21,Pm56Pm21(Pm31)(Haynaldia villosa)[29,30],Pm56(S.cereale)[116]7A Pm1,Pm9,Pm37,Pm59,Pm60Pm1a[31,32],Pm1c(Pm18)[7,33],Pm1e(Pm22)[8],Pm9[34],Pm59[117]Pm1b(T.monococcum)[7],Pm1d(Aegilops speltoides(Ae.speltoides))[7],Pm37(T.timopheevi)[35],Pm60(T.urartu)[81]1B Pm8,Pm28,Pm32,Pm39Pm28[36],Pm39[37]Pm8(Pm17)(S.cereale)[10],Pm32(Ae.speltoides)[38]2B Pm6,Pm26,Pm33,Pm42,Pm49,Pm51,Pm52,Pm57Pm52[1]Pm6(T.timopheevi)[39,40],Pm26(T.dicoccoides)[41],Pm33(T.carthlicum)[42],Pm42(T.turgidumdicoccon)[43],Pm49(T.turgidum dicoccon)[44],Pm51(Thinopyrum ponticum(Th.ponticum))[45],Pm57(Ae.searsii)[46]3B Pm13,Pm41Pm13(Ae.longissima)[47],Pm41(T.turgidumdicoccon)[48]4B Pm7Pm7(S.cereale)[49,50]5B Pm30,Pm36,Pm53Pm30(T.dicoccoides)[51],Pm36(T.turgidumdicoccon)[52],Pm53(Ae.speltoides)[53]6B Pm11,Pm12,Pm14,Pm20,Pm27,Pm54Pm11[54],Pm14[55],Pm54[56]Pm12(Ae.speltoides)[57],Pm20(S.cereale)[49],Pm27(T.timopheevii)[58]7B Pm5,Pm40,Pm47Pm5c[59],Pm5d[59,60],Pm5e[61],Pm47[62]Pm5a(T.dicoccum)[63],Pm5b(T.dicoccum)[59],Pm40(Th.intermedium)[4,64]1D Pm10,Pm24Pm10[65],Pm24a[66,67],Pm24b[68]2D Pm43,Pm58Pm43(Th.intermedium)[69],Pm58(Ae.tauschii)[6]5D Pm2,Pm34,Pm35,Pm46Pm2c[70,71],Pm46(Pm48)[12]Pm2a(Ae.tauschii)[72,73],Pm2b(Agropyroncristatum)[70],Pm34(Ae.tauschii)[74],Pm35(Ae.tauschii)[75]6D Pm45Pm45[76]7D Pm15,Pm19,Pm29,Pm38Pm15[55],Pm38[77]Pm19(Ae.squarrosa)[72,73],Pm29(Ae.ovate)[78]Table2The different distributions of formally named powdery mildew-resistance genes on wheat A,B,and D genomes.Genome Number of loci Number of Pm genes(genes from alien species)Proportion of alien genes Mean number of allelesper average locusA1442(14)0.33 3.00B2732(22)0.69 1.19D1317(8)0.47 1.31S.Tang et al./Engineering4(2018)500–506501Cytological analysis showed that the rye chromosome arm1RS was translocated to the wheat chromosome arm1BL,resulting in the translocation chromosome T1BLÁ1RS[84].In addition to powdery mildew resistance,the rye chromosome arm1RS offers resistance to other diseases such as strip rust(caused by Puccinia striiformis f.sp.tritici[85,86])and possesses desirable agronomic traits that increase wheat yield[87].Hence,Pm8,as a valuable powdery mildew-resistance gene,was widely used in wheat-breeding pro-grams and produced many wheat cultivars with resistance to pow-dery mildew;these include‘‘Kavkaz,”‘‘Apollo,”‘‘Disponent,”and ‘‘CN10,”which have been widely grown around the world [10,88–92].Although some newly emerged Bgt isolates overcame the resistance of Pm8in the1990s[93],the use of Pm8in wheat-breeding programs continued,especially in the21st century, because the wheat-rye1BLÁ1RS translocated chromosome carrying Pm8has other excellent agronomic traits such as wide adaptability, high yield potential,and delayed leaf senescence[87,94].Thus, Pm8has been effective against the powdery mildew pathogen for about60years and has played an important role in wheat resis-tance breeding around the world[95].Another example of the successful use of an alien wheat pow-dery mildew-resistance gene is Pm21.In the early1980s,H.villosa was identified as a potential source of powdery mildew resistance [96],and some alien addition lines and substitution lines devel-oped from H.villosa showed resistance[97].A resistance gene from H.villosa,designated as Pm21,was mapped on the wheat–H.villosa 6VSÁ6AL translocated chromosome[30].The6VSÁ6AL translocation lines carrying Pm21have been widely used as a parent in Chinese wheat-breeding programs because the other resistance genes have been overcome by newly emerged isolates,and because the use of Pm21has little adverse effect on other agronomic traits[98].More than ten wheat cultivars carrying Pm21have been released in China since2002;these include Yangmai5,Yangmai15,Yangmai 18,Neimai8,and Neimai9[30,99,100],which have been grown on more than3.4Â106hm2),and this growth area is rapidly expand-ing,especially since2007[101].Virulence testing revealed that Pm21shows a broad spectrum of resistance,and remains highly effective against most of the isolates of Bgt[102];this indicates that the resistance of Pm21has lasted for more than40years.A few studies reported that new isolates of Bgt were virulent to Pm21[103,104];however,two recent studies demonstrated that Pm21is still effective against1082Bgt isolates collected from eight major wheat-growing regions in China[105],and against1402Bgt isolates collected from19locations in Poland[106].These results suggest that Pm21can still be used as a pivotal powdery mildew-resistance gene in wheat-breeding programs in the future.2.2.The great potential of Pm40in wheat resistance breedingIn2007,we identified two powdery mildew-resistant wheat lines,Yu24and Yu25.These two wheat lines were derived from the cross between the wheat cultivar Chuanmai107and the octo-ploid Tritigrigia TAI7047,where the TAI7047was derived from the cross between T.aestivum cv.Taiyuan768/Th.intermedium// T.aestivum line76(64).Genetic analysis suggested that the pow-dery mildew resistance was controlled by two pairs of Mendelian genes[107].One of the genes,Pm40,was assigned to wheat chromosome arm7BS by microsatellite markers[64].Pm40is highly effective and durable against many Bgt isolates. The powdery mildew resistance of both Yu24and Yu25was origi-nally observed over several consecutive years infields at the Ya’an Agricultural Research Station of Sichuan Agricultural University in southwest China,where the climate is warm and humid,with a yearly average temperature of15–17°C and an average annual precipitation of1520mm[64].These weather conditions favor epidemics of wheat diseases,and there exists a large variation in the virulence of Bgt[4].These observations suggest that Yu24 and Yu25may be resistant to various Bgt isolates.In fact,the resis-tance conferred by Pm40is still effective infields located in the Chinese provinces of Henan,Shandong,Hebei,and Fujian[102].A powdery mildew-resistance test in a greenhouse at the Institute of Crop Science,Chinese Academy of Agricultural Science,Beijing, demonstrated that the resistance in wheat line L658,conferred by Pm40,was resistant to all28of the Bgt isolates collected from various regions of China.This test displayed the board-spectrum and putatively durable character of Pm40(Table3[5]and Fig.1), suggesting that Pm40holds great potential to be an important powdery mildew-resistance gene in wheat-breeding programs.Pm40can be quickly integrated into commercial wheat cultivars.Alien chromosomal translocation has been a common and useful bridge for transferring genes from wild relatives to com-mon wheat.However,the‘‘linkage drag”that transfers other linked genes for undesirable traits together with the target gene from the alien translocation is a major drawback to the use of these resistance sources in breeding[108].The original wheat lines Yu24and Yu25,which were derived from the wild cross between common wheat and Th.intermedium,showed good genetic stability of powdery mildew resistance along with uniform agronomic traits in thefield[107,109].In addition,Pm40inherits as a normal Men-delian unit,and there are wheat-specific products in the resistant parent produced by polymerase chain reaction(PCR)amplifying.A wheat marker linked to Pm40and the closely linked DNA marker lociflanking Pm40show good agreement in loci order andflanking marker distances with the consensus genetic map[64].No alien chromosomal segment is detected by in situ hybridization in any of the wheat lines carrying Pm40[4,110].The good stability of the powdery mildew resistance conferred by Pm40ensures thatTable3Infection types on wheat seedlings inoculated with Bgt isolates from different areas.Isolate Source Wheat line(gene)Coker747(Pm6)Liangxing99(Pm52)L658(Pm40) Bgt68-2Beijing000Bgt74-1Hebei300Bgt87Beijing300Bgt74-3Hebei300Bgt86-3Jiangsu200Bgt75-1Henan200Bgt75-2Henan300Bgt82-3Shandong000Bgt88-3Shandong300Bgt77-1Henan300Bgt83-1Shandong000Bgt81-2Shandong400Bgt68-1Beijing100Bgt69-1Hebei300Bgt82-2Shandong000Bgt78-3Henan200Bgt79-2Shandong330Bgt44-6Shandong330Bgt76-3Henan300Bgt78-2Henan300Bgt68-3Beijing100Bgt73-3Hebei100Bgt72Hebei200Bgt71-2Hebei200Bgt44-4Shandong030Bgt79-3Shandong230Bgt75-3Henan320Bgt28Sichuan——00:no visible symptoms;1:hypersensitive necroticflecks and small conidia with few conidiospores;2:colonies with moderately developed conidia;3:colonies with well-developed hyphae and abundant disconnected conidia;4:well-developed hyphae and joined conidia[5].502S.Tang et al./Engineering4(2018)500–506it can be quickly integrated into commercial wheat cultivars by molecular breeding methods.The wheat lines containing Pm40usually have desirable agronomic traits and can easily be used in future Chinese wheat breeding.Breeders usually pay more attention to overall agronomic performance and to the effectiveness of resistance transferring than to where the resistance genes come from [4].To accelerate the deployment of Pm40in wheat-breeding programs,we have developed some Pm40wheat lines,including L658(PI 672537),L693(PI 672538),L696(PI 672539),and L699(PI 672540).Many of these lines exhibit excellent agronomic traits such as good plant height,yield index,head weight,and thousand kernel weight.They also show resistance to multiple diseases [111];for example,YrL693confers resistance to stripe rust [112],while FhbL693a and FhbL693b confer resistance to Fusarium head blight (caused by Fusarium gramineum )[110].Molecular markers closely linked with Pm40have been identified.For example,we have identified two simple sequence repeats (SSRs)markers,Xwmc335and Xgwm297,and two sequence-tagged site-based expression-sequence tags (EST-STS),BF291338and BE446359.Both markers were less than one centimorgan to Pm40[4,64],which thus provides a useful tool for breeders to effectively transfer Pm40into commercial wheat cultivars using molecular marker-assistant selection.Finally,information on chlorophyll content,photosynthetic and chlorophyll fluorescence parameters,antioxi-dant activity,and gene expression after Bgt infection could be used as an additional reference for breeders in breeding practices [109].Therefore,wheat lines containing Pm40are promising for the improvement of both yield and multiple disease resistance;in addition,the availability of the closely linked marker paves the way for breeders to achieve an effective transfer of Pm40into commercial wheat cultivars.3.Deployment of powdery mildew-resistance wheat genes post-Pm21in ChinaSeveral new isolates of Bgt have been reported to be virulent to Pm21[103,104].This indicates a forthcoming risk of powdery mildew epidemics in Chinese wheat production due to the loss of resistance of Pm21.Therefore,wheat breeders need to identify a replacement for Pm21for powdery mildew-resistance improve-ment.Among the published Pm genes,Pm40was derived from Th.intermedium and confers strong resistance to powdery mildew with a broad resistance spectrum [5].In addition,wheat lines carrying Pm40usually have good yield traits,plant type,and resis-tance to other diseases such as stripe rust and Fusarium head blight [111].Moreover,the stability of Pm40resistance and the molecular markers that are closely linked to Pm40[4,64]make it a good candidate for the replacement of Pm21.To effectively use Pm40in wheat breeding,we suggest that pyramiding of Pm40as themajor provider of resistance,along with the other Pm genes is an important strategy to control wheat powdery mildew.4.Durability and effectiveness of alien resistance genes A wheat–Th.intermedium introgression line was recently shown to have a broader spectrum of resistance against different Bgt iso-lates than the genes from wheat in popular resistant cultivars [3].For stripe rust wheat resistance,several alien Yr genes,such as Yr5derived from T.spelta album [113],Yr9from rye [114],Yr15from T.dicoccoides [115],and Yr26from T.turgidum [116],have a broader spectrum of resistance against Pst than the Yr genes derived from common wheat.Although Yr9has lost its resistance to Pst races CYR29,CYR31,CYR32,and CYR33[90],it has played an important role in the improvement of wheat resistance to stripe rust.Yr26is a major stripe rust-resistance gene that has been widely used in breeding and is still effective against current Pst races.Polymor-phism at the loci that were derived from wide crossing contributes to parasite recognition,which will prevent loss of fitness due to dis-ease;the more heterogeneous the host,the more incompatible it will be with pathogens [117].Therefore,alien resistance genes usu-ally provide a broader resistance spectrum and more potentially durable resistance than genes derived from crop itself.We assume that the larger variation in the DNA sequence of alien resistance genes,as compared with the genes from wheat,results in an increased resistance spectrum and in a delayed process of compat-ible reaction between the host and pathogens in alien genes.This hypothesis will provide new insight into selecting powdery mildew-resistance genes to be deployed in breeding programs in the future.5.ConclusionWith its broad resistance spectrum,Pm40,as one of the impor-tant Pm genes derived from alien species or sporadically grown subspecies,could play a key role in the improvement of Chinese wheat resistance to powdery mildew.The potential of Pm40has become even more important since the powdery mildew resis-tance conferred by Pm21has been overcome by newly emerged Bgt isolates.In addition,further elucidation of the resistance mech-anism of Pm40would accelerate its application in wheat-breeding programs.AcknowledgementsWe are grateful to Dr.Hongjie Li of the Institute of Crop Sciences,Chinese Academy of Agricultural Sciences,China,for pro-viding many useful suggestions and for revising this manuscript.We are also grateful for financial support from the NationalNaturalFig.1.Powdery mildew responses on infected leaves of Pm40.(a)Wheat line L658(Pm40)in the field;(b)infected leaves of the wheat lines L658(resistant)and MY11(susceptible)in the greenhouse 14days after inoculation;(c)infected leaves of wheat lines L658and MY11in the field.S.Tang et al./Engineering 4(2018)500–506503Science Foundation of China(31571661)and the Applied Basic Research Foundation of the Science and Technology Department of Sichuan Province of China(2017JY0012).Compliance with ethics guidelinesShengwen Tang,Yuting Hu,Shengfu Zhong,and Peigao Luo declare that they have no conflict of interest orfinancial conflicts to disclose.References[1]Zhao Z,Sun H,Song W,Lu M,Huang J,Wu L,et al.Genetic analysis anddetection of the gene MlLX99on chromosome2BL conferring resistance to powdery mildew in the wheat cultivar Liangxing99.Theor Appl Genet 2013;126(12):3081–9.[2]Luo PG,Hu XY,Chang 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北京市西城区2021届新高考第四次质量检测生物试题一、单选题（本题包括25个小题，每小题2分，共50分．每小题只有一个选项符合题意）1．普通小麦6n=42，记为42E；长穗偃麦草2n=14，记为14M，长穗偃麦草中某条染色体含有抗虫基因。
下图为普通小麦与长穗偃麦草杂交选育抗虫小麦新品种的过程。
据图分析，下列正确的是（）A．普通小麦与长穗偃麦草不存在生殖隔离，杂交产生的F1为四倍体B．①过程目前效果较好的办法是用秋水仙素处理萌发的种子或幼苗C．丙中来自长穗偃麦草的染色体数目为3M或4MD．③过程利用辐射诱发染色体发生易位后即可得到戊【答案】D【解析】【分析】本题结合图解，考查生物变异及其应用，分析题图：图示为普通小麦与长穗偃麦草杂交选育抗虫小麦新品种的过程．先将普通小麦与长穗偃麦草杂交得到F1，①表示人工诱导染色体数目加倍（常用秋水仙素处理幼苗）获得甲；再将甲和普通小麦杂交获得乙，乙再和普通小麦杂交获得丙，经过选择获得丁，最终获得染色体组成为42E的戊。
【详解】A、普通小麦长穗偃麦草杂交产生的后代F1不育，存在生殖隔离，不是同一个物种，A错误；B、F1不含同源染色体，不可育，因此①过程目前效果较好的办法是用秋水仙素处理幼苗，不能处理萌发的种子，B错误；C、分析题图可知，乙中来自燕麦草的染色体组是一个，因此乙中长穗偃麦草的染色体不能联会，产生的配子的染色体数目是21+0～7M，因此丙中来自长穗偃麦草的染色体数目为0～7M，C错误；D、③过程利用辐射诱发染色体发生易位和数目变异后可得到戊，D正确。
故选D。
2．雾霾是特定气候条件与人类活动相互作用的结果。
高密度人口的经济及社会活动必然会排放大量细颗粒物（PM 1．5），一旦排放超过大气循环能力和承载度，细颗粒物浓度将持续积聚，此时如果受静稳天气等影响，极易出现大范围雾霾。
下列有关叙述错误的是（）A．从生态系统的成分分析，雾霾属于非生物的物质和能量B．从生态系统的信息传递分析，雾霾可作为物理信息影响种群繁殖C．从生态系统稳定性分析，雾霾说明生态系统的自我调节能力丧失D．从生态系统的保护分析，雾霾是人类生产和生活所造成的环境污染【答案】C【解析】【分析】1、雾霾的组成：二氧化硫、氮氧化物和可吸入颗粒物是雾霾的主要组成。
