61份大麦种质资源对蠕孢菌叶斑病的抗性鉴定

 麦根腐平脐蠕孢菌[Bipolaris sorokiniana(Sacc.)Shoemaker]引起的叶斑病是大麦上重要的病害叶部之一,在世界各大麦主要种植区均能造成严重的经济损失。本研究利用3个致病力不同的蠕孢叶斑病菌株Z 12010、Z 12014和Z 13010分别对来源于中国及国外引进的61份大麦种质资源进行苗期抗蠕孢菌叶斑病鉴定,田间接种Z 12014菌株进行成株期抗病性鉴定。在所鉴定的大麦种质中未发现在苗期或成株期对叶斑病免疫的材料。苗期抗叶斑病分析发现,品种之间对3个菌株的抗性存在明显差异,Varunda、Legacy、Tradition、09GW-01、09GW-07、08PJ-36、09PJ-39、垦啤麦7号、垦啤麦10号、驻大麦3号、S-4和中饲麦1号等12份材料对3个菌株表现为中抗至高抗反应型。7份材料成株期抗Z 12014菌株,其中Legacy、蒙啤麦3号、09PJ-39、垦啤麦9号、垦啤麦11号和龙啤麦3号等6份材料具有全生育期抗性特点,品种10-3苗期对菌株Z 12014感病,而成株期抗该菌株。     

61份大麦种质资源对蠕孢菌叶斑病的抗性鉴定

 麦根腐平脐蠕孢菌[Bipolaris sorokiniana(Sacc.)Shoemaker]引起的叶斑病是大麦上重要的病害叶部之一,在世界各大麦主要种植区均能造成严重的经济损失。本研究利用3个致病力不同的蠕孢叶斑病菌株Z 12010、Z 12014和Z 13010分别对来源于中国及国外引进的61份大麦种质资源进行苗期抗蠕孢菌叶斑病鉴定,田间接种Z 12014菌株进行成株期抗病性鉴定。在所鉴定的大麦种质中未发现在苗期或成株期对叶斑病免疫的材料。苗期抗叶斑病分析发现,品种之间对3个菌株的抗性存在明显差异,Varunda、Legacy、Tradition、09GW-01、09GW-07、08PJ-36、09PJ-39、垦啤麦7号、垦啤麦10号、驻大麦3号、S-4和中饲麦1号等12份材料对3个菌株表现为中抗至高抗反应型。7份材料成株期抗Z 12014菌株,其中Legacy、蒙啤麦3号、09PJ-39、垦啤麦9号、垦啤麦11号和龙啤麦3号等6份材料具有全生育期抗性特点,品种10-3苗期对菌株Z 12014感病,而成株期抗该菌株。     

不同小麦品种资源苗期和成株期麦长管蚜抗性鉴定和分析

为明确小麦苗期和成株期与麦长管蚜抗性的关系,2010—2012年采用蚜量比值法对94个小麦品种进行了温室苗期人工接种和田间成株期自然感蚜麦长管蚜抗性鉴定。结果表明,43个品种连续3年在成株期对麦长管蚜表现不同程度的抗性,其中高抗品种2个,中抗品种8个,低抗品种33个;45个品种在苗期对麦长管蚜表现不同程度的抗性,其中高抗品种5个,中抗品种16个,低抗品种24个;30个品种在苗期和成株期同时表现抗蚜,占供试品种的31.91%,其中C273和兰麦（陕西柞水）在苗期和成株期均表现为高抗;小麦品种在温室苗期人工接种和田间成株期自然感蚜的蚜量比值呈极显著正相关,苗期和成株期麦长管蚜抗性表现一致的共有66个品种,占供试材料的70.21%。研究表明温室苗期人工接种是快速鉴定小麦品种麦长管蚜抗性的有效方法。     

81份春小麦种质资源抗条锈病评价

本研究结合苗期分小种接种和大田成株期自然诱发条件下对供试的81份春小麦资源进行抗条锈病鉴定,分析其抗条锈病情况、抗病类型及抗病性关系,结果表明:具全生育期抗条锈病类型的资源有7份,具成株期抗条锈病类型的资源有39份,有30份资源为含有成株期和对部分小种失去抗性的全生育期抗病性的抗性类型;苗期分别接种7个小种后,表现抗病的资源数为9~25份不等,表现中抗的资源为2~6份不等,表现感病的有50~69份不等,成株期表现抗病的73份,表现中抗的3份,感病的5份,即供试种质资源大部分表现为苗期感病,而成株期具有抗病性。聚类分析结果表明,该81份种质资源抗性聚类相对分散,遗传多样性水平较高。研究结果为小麦育种提供优良的抗条锈性资源。     

远缘杂交衍生后代中筛选小麦抗条锈病新抗源

 针对小麦远缘杂交的一系列衍生系,在陕西杨凌人工条锈病圃(CYR32和CYR33混合小种)选择压力下,兼顾抗病性与农艺性状,经过连续6年系统选择,筛选了106份远缘杂交衍生后代选系。在此基础上,通过杨凌人工混合小种接种鉴定圃和甘肃天水自然诱发鉴定圃,对其进行成株期抗条锈病鉴定;利用当前流行小种CYR32、CYR33和G22-9进行苗期分小种鉴定;结合Yr26的分子标记检测评估抗源价值。建立基于成株期与苗期抗病性鉴定相结合,异地抗病表型鉴定与分子标记筛查的抗源筛选和评价体系。结果表明:106份远缘杂交后代衍生系中,筛选出54个能够抵抗包括G22-9在内的多个流行小种的选系;结合标记筛查结果,筛选到36份不含Yr26的抗病材料,其中4份为全生育期抗条锈病性类型(ASR),32份为成株期抗性(APR)类型。推测这些抗性选系可能具有抗条锈病新基因。     

四川省育成小麦品种和高代品系对条锈病的抗病性评价

四川省不仅是条锈菌冬繁区,也是我国东部麦区重要的春季初侵染菌源地和毒性变异地。准确评价四川小麦新育成品种和高代品系对条锈病的抗性水平,能为合理培育和使用抗病品种提供重要依据。利用当前条锈菌优势小种和4个地点的成株期鉴定圃对来自四川省的115份小麦育成品种和299份高代品系进行苗期和成株期抗病性鉴定。结果表明,新育成品种苗期对优势小种的高抗CYR32、CYR33和CYR34的比例发生不同程度的变化,对CYR32的高抗比例为40.9%、对CYR34的高抗比例为17.4%,而供试高代品系高抗比例从52.3%降至46.2%;中抗类型育成品种从20.0%增加到40.9%,高代品系从19.6%增加至33.2%。表明条锈菌优势小种更替后一些材料仍保留了部分抗性,后期选育的高代品系兼顾对新小种的抗病性。育成品种在四川成都和甘肃清水成株期鉴定,高抗品种所占比例较低,分别为13.9%和3.5%,但高代品系高抗类型比例较高,分别为42.2%和8.5%,表明甘肃和四川条锈菌的致病类型和发病环境条件存在较大差异,近年来四川小麦成株抗条锈病育种取得显著进展。     

水稻品种苗期阶段对白叶枯病的抗性研究

 根据水稻品种各叶期对白叶枯病的抗性表现和强弱程度可分为四类:(1)全期抗病型;(2)全期中抗型;(3)苗感成株抗病型;和(4)全期感病型。可以看出,水稻品种除少数苗感成抗型外,其余三种抗性类型苗期与成株期的抗性反应是一致的。由于中抗、成抗和感病品种各叶期的抗性有随着叶位的升高而抗性增强的趋势,不同抗性品种在苗期阶段抗感对比均较成株期明显。因此,水稻品种对白叶枯病的抗性鉴定采用苗期鉴定方法是可行的。影响水稻品种苗期抗性的因素是:苗龄(叶期)、观察时期、品种与菌株的组合等。     

大麦抗条纹病与SSR标记的关联分析

为了解不同来源大麦的遗传多样性,并筛选与抗条纹病性状相关联的SSR标记,采用三明治法通过人工接种大麦条纹病菌Pyrenophora graminea对180份大麦材料进行抗性鉴定,通过119对多态性SSR引物对180份大麦材料进行SSR标记分析,并用一般线性模型(general lineal model,GLM)和混合线性模型(mixed lineal model,MLM)进行大麦抗条纹病与SSR标记的关联分析。结果表明,人工接种大麦条纹病菌后共鉴定出10份免疫、9份高抗、25份抗病、70份感病和66份高感大麦材料;119对多态性SSR引物从180份大麦材料中共检测出559个等位变异位点,平均为4.70个,变幅为2～14个,基因多样性和多态性信息含量变幅分别为0.05～0.88和0.05～0.86;群体结构分析表明供试大麦材料可分为2个亚群。基于GLM和MLM分别检测到14个和10个与大麦条纹病抗性相关联的SSR标记,对表型变异的解释率变幅分别为4.46%～9.76%和3.25%～7.87%,其中Scssr08238和BMS64标记均与大麦条纹病抗性呈极显著相关,二者在GLM中解释率分别为9.76%和8.00%,在MLM中解释率分别为7.87%和5.61%。本研究所鉴定的大麦抗性种质可作为抗源用于抗病育种,与抗性相关联的SSR标记可用于大麦抗条纹病的分子标记辅助选择育种。     

陕甘川豫主要后备小麦品种对中国条锈菌优势种群苗期抗性的聚类分析

为了弄清我国小麦条锈病主要流行区后备小麦品种的抗锈性,选用6个条锈菌优势菌系,对陕、甘、川、豫四省近年来培育的200份后备小麦品种进行苗期和成株期鉴定,并分别对不同省份后备品种的抗条锈性进行聚类分析。结果表明,供试品种对我国条锈菌优势种群的抗锈性表现为:四川省后备品种抗锈性最强,对供试菌系全免的品种占80.82%;其次为陕西省和甘肃省,分别为52.73%和50.00%,河南省的最弱,全免的品种仅占22.22%;从抗性类型种类和分布来看,陕西省后备品种抗性分化明显,中间类型少,甘肃省品种的抗性类型分布比较均匀,表明陕西省后备品种的抗锈基因较单一,甘肃省后备品种中所含的抗病基因类型复杂,显示甘肃省近年来重视抗源多样化育种带来了成效;成株期抗锈品种数量明显多于苗期,表明后备品种中存在大量的成株抗锈品种。     

89份河北、山西小麦品种抗条锈性评价及抗条锈病基因检测

为明确北部麦区河北、山西育成品种对中国小麦条锈病的抗性水平及部分已定位抗条锈病基因的分布状况, 利用小麦条锈菌当前优势小种CYR32、CYR33和CYR34对89份来自河北、山西的小麦品种在温室进行苗期分小种抗性鉴定, 在小麦条锈病不同流行区甘肃清水、四川郫县、湖北荆州设置鉴定圃进行成株期抗性鉴定; 采用与部分已知基因紧密连锁的分子标记进行抗病基因检测。结果显示, 苗期仅‘长4640’‘晋麦91号’‘科农2009’3份品种对CYR32、CYR33和CYR34均表现抗性; 在甘肃清水、四川郫县、湖北荆州鉴定圃中抗病材料的比例分别为39.33%、24.72%和58.43%, ‘长4640’和‘晋麦91号’为全生育期抗性。通过6个已知抗条锈基因Yr5、Yr9、Yr10、Yr15、Yr18 和Yr26 对89份小麦品种进行分子标记检测, 结果表明, 13份品种检测到Yr9标记, 2份检测到Yr18标记, 未检测到Yr5、Yr10、Yr15和Yr26。以上结果表明, 河北、山西小麦品种对越冬菌源基地的条锈菌的抗性水平很低, 同时成株期抗性基因的利用率低, 今后应加强对新抗病基因的利用, 育种过程中尽可能在不同流行区进行异地鉴定。     

Molecular mapping of Loci conferring resistance to different pathotypes of the spot blotch pathogen in barley

ABSTRACT Spot blotch, caused by Cochliobolus sativus, is an important disease of barley in many production areas and is best controlled through the deployment of resistant cultivars. Information on the genetics of resistance in various sources can be useful in developing effective breeding strategies. Parents of the doubled haploid mapping population Calicuchima-sib/ Bowman-BC (C/B) exhibit a differential reaction to pathotypes 1 and 2 of C. sativus. To elucidate the genetics of spot blotch resistance in this population, C/B progeny were evaluated with both pathotypes at the seedling stage in the greenhouse and at the adult plant stage in the field. At the seedling stage, progeny segregated 84 resistant to 26 susceptible based on the qualitative analysis of infection response (IR) data to pathotype 1. This fit best to a 3:1 ratio, indicating that two genes were involved in conferring resistance. Quantitative analysis of the raw IR data to pathotype 1 revealed a single quantitative trait locus (QTL) on chromosome 4(4H) explaining 14% of the phenotypic variance. Adult plant resistance to pathotype 1 was conferred by QTL on chromosome 2(2H) and chromosome 3(3H), explaining 21 and 32% of the phenotypic variation, respectively. Bowman contributed the resistance alleles on chromosome 3(3H) and chromosome 4(4H), whereas Calicuchima-sib contributed the resistance allele on chromosome 2(2H). Resistance to pathotype 2 was conferred by a single gene (designated Rcs6) on chromosome 5(1H) based on qualitative analysis of data. Rcs6 was effective at both the seedling and adult plant stages and was contributed by Calicuchima-sib. This result was corroborated in the quantitative analysis of raw IR (seedling stage) and disease severity (adult plant stage) data as a single major effect (r(2) = 0.93 and 0.88, respectively) QTL was identified on chromosome 5(1H). Progeny with resistance to both pathotypes were identified in the C/B population and may be useful in programs breeding for spot blotch resistance.     

A Compromised Mlo Pathway Affects the Response of Barley to the Necrotrophic Fungus Bipolaris sorokiniana (Teleomorph: Cochliobolus sativus) and Its Toxins

ABSTRACT In search of new durable disease resistance traits in barley to control leaf spot blotch disease caused by the necrotrophic fungus Bipolaris sorokiniana (teleomorph: Cochliobolus sativus), we developed macroscopic and microscopic scales to judge spot blotch disease development on barley. Infection of barley was associated with cell wall penetration and accumulation of hydrogen peroxide. The latter appeared to take place in cell wall swellings under fungal penetration attempts as well as during cell death provoked by the necrotrophic pathogen. Additionally, we tested the influence of a compromised Mlo pathway that confers broad resistance against powdery mildew fungus (Blumeria graminis f. sp. hordei). Powdery mildew-resistant genotypes with mutations at the Mlo locus (mlo genotypes) showed a higher sensitivity to infiltration of toxic culture filtrate of Bipolaris sorokiniana as compared with wild-type barley. Mutants defective in Ror, a gene required for mlo-specified powdery mildew resistance, were also more sensitive to Bipolaris sorokiniana toxins than wild-type barley but showed less symptoms than mlo5 parents. Fungal culture filtrates induced an H2O2 burst in all mutants, whereas wild-type (Mlo) barley was less sensitive. The results support the hypothesis that the barley Mlo gene product functions as a suppresser of cell death. Therefore, a compromised Mlo pathway is effective for control of biotrophic powdery mildew fungus but not for necrotrophic Bipolaris sorokiniana. We discuss the problem of finding resistance traits that are effective against both biotrophic and necrotrophic pathogens with emphasis on the role of the anti-oxidative system of plant cells.     

中国不同春麦区小麦地方种质抗条锈病评价及抗性基因分析

为明确中国不同春麦区小麦地方种质对当前小麦生产上流行的条锈病菌Puccinia striiformis f.sp.tritic的抗性水平及其所含抗性基因,利用条锈病菌生理小种条中32（CYR32）和条中34（CYR34）及混合生理小种（致病类群）对来自5个春麦区的196份小麦地方种质进行苗期、成株期抗性鉴定,并通过6个已知条锈病抗性基因Yr9、Yr18、Yr26、Yr48、Yr65和Yr67对其所含重要抗性基因进行分子标记检测。结果显示,在苗期,有11份小麦地方种质对CYR32表现出抗性,有12份对CYR34表现出抗性,分别占供试种质总数的5.61%和6.12%;有6份对CYR32和CYR34均表现出抗性;在成株期,有59份小麦地方种质在5个田间诱导环境下表现出稳定的抗性。有119份小麦地方种质检测到含抗性基因,其中有3份携带Yr9,有50份携带Yr18,有43份携带Yr48,有54份携带Yr65,所有供试种质均未检测到Yr26和Yr67,抗性基因的组合分析发现,共有31份小麦地方种质携带4种抗性基因组合类型Yr9+Yr18、Yr18+Yr48、Yr18+Yr65和Yr48+Yr65。表明来自中国5个春麦区的小麦地方种质条锈病抗性表型呈多样性,且携带目前在小麦抗病育种和生产上有效的条锈病抗性基因（组合）,建议加大对小麦地方种质的保护和应用力度。     

Assessing genetic resistance to spot blotch, <Emphasis Type="Italic">Stagonospora nodorum</Emphasis> blotch and tan spot in wheat from Nepal

Fungal leaf spot diseases of wheat (Triticum aestivum L.) in Nepal cause significant yield reduction. Although field testing has identified a few partially resistant cultivars, most wheat grown in Nepal lacks adequate resistance to leaf spot diseases. During 2009–2010, 116 local and commercial spring wheat cultivars and advanced breeding lines were selected from multi-year field experiments in Nepal and evaluated for seedling resistance to three leaf spot diseases: spot blotch, Stagonospora nodorum blotch (SNB) and tan spot races 1 and 5 (two of the most prevalent races) in the growth chambers at North Dakota State University, Fargo, ND, USA. The wheat cultivars and lines were artificially inoculated with individual pathogens or races at the two-leaf stage and disease reactions were evaluated 6 to 10 days after inoculation (DAI). Results indicated that 30%, 31%, 19% and 10% of the tested wheat cultivars and lines were resistant to spot blotch, SNB, tan spot races 1 and 5, respectively. Six advanced breeding lines (SW89-5422, BL 2127 = DANIAL88/HLB30//NL297, BL 3033, FILIN/IRENA/5/CNDO/R143//ENTE/MEXI-2/3/AE. SQUA (TAUS)/4WEAVER, GAN/AE.SQUARROSA (236)//DOY1/AE.SQUARROSA(447)/3/MAIZ/4/INQALAB91, Mayoor//TK SN1081/Ae. Squarrosa (222)/3/FCT, were resistant to spot blotch, SNB and tan spot race 1. Similarly, two wheat cultivars Chirya 3 and Chirya 7 were resistant to spot blotch, and tan spot races 1 and 5. The resistant wheat lines identified in this study represent potentially useful and untapped sources of resistance to multiple leaf spot diseases and should be utilized in wheat breeding programs in Nepal in order to develop wheat cultivars with broad-spectrum resistance.     

野生稻转育后代对褐飞虱抗性的研究

对１０７份栽培稻／野生稻高世代品系及８６个药用野生稻栽培稻回交Ｆ１再生苗进行了苗期抗褐飞虱鉴定,对６４个品系进行了孕穗期抗性鉴定,并初步了野生稻转育后代的苗期拒虫性及孕穗期抗生性等。结果表明,野生稻抗虫基因已导入某些杂交品系Ｂ５,Ｂ２,Ｂ３,Ｂ６,Ｂ１０,Ｂ１１,Ｂ１２,Ｂ１３,Ｂ１４,Ｂ１５,Ｂ７,Ｂ８在苗期表现高抗,在孕穗期表现中抗,抗性水平比对照抗性品种ＩＲ３６高;Ｂ２Ｆ３－５２,Ｂ２Ｆ３－     

黄淮麦区主栽小麦品种抗茎基腐病评价及茎秆和籽粒中毒素积累分析

为明确黄淮麦区主栽小麦品种对茎基腐病的抗性水平、不同抗性指标的相关性,以及茎杆和籽粒中镰刀菌毒素积累情况,在采用苗期茎基部滴注法和成株期混合播种法进行抗性鉴定的基础上,本研究还利用超高效液相色谱高分辨质谱联用技术,测定了小麦茎杆和籽粒中6种常见镰刀菌毒素的含量.结果表明,供试的20个小麦品种中,苗期抗病、中抗、感病和高...     

Vavilov wheat accessions provide useful sources of resistance to tan spot (syn. yellow spot) of wheat

Host genetic resistance is the most effective and sustainable means of managing tan spot or yellow spot of wheat. The disease is becoming increasingly problematic due to the adoption of minimum tillage practices, evolution of effector‐mediated pathogenicity, and widespread cultivation of susceptible cultivars from a narrow genetic base. This highlights the importance of broadening the diversity of resistance factors in modern breeding germplasm. This study explored 300 genetically diverse wheat accessions, originally sourced from the N. I. Vavilov Institute of Plant Genetic Resources (VIR), St Petersburg, Russia. The collection was screened for resistance to tan spot at seedling and adult stage under controlled conditions, and in the field across 2 years. The phenotypic datasets, coupled with ToxA bioassay screening, identified a number of accessions with useful sources of resistance. Seedling disease response corresponded well with ToxA sensitivity (r = 0.49, P < 0.000), but not adult responses (r = ?0.02 to ?0.19, P < 0.002), and overall reactions to ToxA appeared to show poor correspondence with disease response at the adult stage. ToxA‐insensitive accessions were generally found resistant across different growth stages (all‐stage resistance, ASR) in all experiments (seedling and adult stage under controlled conditions and field). ToxA‐sensitive accessions that were susceptible at seedling stage, but resistant at both adult‐plant stages, were deemed to carry adult‐plant resistance (APR). This study provides detailed information on the degree of tan spot resistance in the Vavilov wheat collection and discusses strategies to harness these sources to boost the diversity of resistance factors in modern wheat breeding germplasm.