小麦抗条锈病基因的研究进展

条锈病是由条锈菌(Puccinia striiformis f. sp. tritici)引起的我国最重要的小麦病害之一,由于小麦条锈菌的高度变异性,加之大面积种植单一抗病品种,致使其丧失原有抗性.因此抗小麦条锈病基因的研究在小麦抗病品种选育中起到举足轻重的作用.本文通过对小麦抗条锈病基因的来源,基因定位,分子标记,基因克隆,基因聚合等方面进行阐述,为小麦抗条锈病育种提供理论依据.     

小麦抗条锈病基因定位及分子标记研究进展

总结了近十几年抗条锈基因的染色体定位和目前抗条锈基因分子标记研究资料及研究报告，重点介绍了抗性基因所在染色体，遗传方式，载体品种和现有分子标记，为利用抗条锈基因(Yr)的利用和研究提供参考。目前已找到分子标记的抗条锈基因有：Yr5、Yr7、Yr8、Yr10、Yr17、Yr26和Yrmoro，共获得标记14个，命名和新基因源的研究和利用工作有待加强。     

从F1的抗条锈病性测定小麦品种抗病性遗传能力

在小麦抗条锈病育种实践中,我们经常发现同一抗源亲本品种和不同的感病农艺亲本杂交后,其F₁对小麦条锈病菌的反应型有所不同,即抗病品种的抗性在后代中的表现因另一亲本不同而有差异。1984年我们从新引进的抗病材料中,     

河南省小麦品种（系）遗传多样性和抗条锈性分析

为评价2008－2011年河南省参加全国小麦区试品种（系）的遗传多样性和抗条锈性,采用亲缘系数（ Coeffi-cient of parentage ,COP）分析方法,对参试的91个小麦品种（系）的遗传多样性进行聚类分析,并利用我国当前或曾是小麦条锈菌流行小种和新的致病类型的混合菌系进行抗条锈性鉴定与评价。结果显示,在供试的91个品种（系）的4095个组合中,约46．13％的品种（系）间存在遗传相似性,所有供试品种（系）的COP值为0．0000～1．0000,亲缘系数总和为423．9662,平均值为4．6590;通过COP值的聚类分析,将供试材料分为10大类,抗病品种占61．54％。4年间,参试品种（系）的遗传相似性逐年提高,遗传多样性下降,而抗条锈性呈上升趋势,这可能与周麦13和周麦16的广泛利用有关。     

青海春小麦品种高原363成株期抗条锈病基因遗传模型分析

为明确青海春小麦品种高原363成株期抗条锈性遗传基础,分别以成株期抗条锈性青海春小麦品种高原363与感病春小麦品种Taichung 29(T29)杂交并自交创建F_(2∶3)分离群体,通过在青海省西宁市和海东市互助县2个试验地点各2 a的田间病圃抗病性鉴定,使用单个分离世代分析法用植物数量性状主基因+多基因混合遗传模型分析高原363/T29 F_2群体的抗性遗传效应。F_(2∶3)群体的反应型和严重度的频率分布结果表明,高原363/T29 F_(2∶3)群体的病害严重度和反应型在西宁和互助共2个环境2 a测试下呈现双峰分布,没有出现连续性分布现象,但是又出现了不同区段内连续性变化,初步分析认为,高原363对小麦条锈病的成株期抗性是一种复杂遗传,这种遗传不仅仅由主效基因控制,同时还受到微效多基因控制,遗传模型分析结果表明,在2个不同地点测试下的高原363,无论是采用严重度数据得出的最优遗传模型还是使用反应型数据得出的最优遗传模型,都是被微效基因影响的2对主基因遗传,并且主基因的作用方式(C-1:2MG-ADI加性-显性-上位性,C-5:2MG-AED完全显性,C-6:2MG-EEAD等显性)是不同的。     

重要抗源京核8811品系抗小麦条锈病主效基因的单体分析

采用单体分析技术，用中国小麦条锈菌优势小种CY31和埃塞俄比亚菌系35E134的单孢菌系对重要抗源京核8811品系进行抗条锈基因分析及定位。结果表明：京核8811含有抗35E134菌系、位于2A染色体上和抗CY31菌系、位于4D染色体上的两对显性抗条锈基因，二者均控制0-0;的侵染型。异同比较显示，定位基因不同于国际上已定名的抗条锈基     

小麦遗传资源抗白粉病基因的STS标记检测

从小麦中筛选抗白粉病基因,为小麦抗病育种提供抗病亲本,为育种后代抗病基因鉴定提供理论依据和技术支撑。以河北省保存的65份小麦遗传资源为材料,利用STS标记技术,对其所携带的抗白粉病基因进行检测。结果表明:检测出携带Pm21、Pm4a和csLV34抗白粉病基因的品种各一个,分别为金禾7178、河农7069和秋麦。这些资源可以作为抗病亲本在小麦抗白粉病育种中利用。     

Genes for resistance to stripe rust in four spring wheat varieties

Summary The stripe rust resistant spring wheat (Triticum aestivum L.) varieties Anza, Glennson 81, Ollanta, and Yecora Rojo gave 1,2,2, and 2-gene segregations, respectively, in hybrids with susceptible Jupateco 73 when inoculated in field conditions at Davis, California USA with Puccinia striiformis West. pathotype CDL-6 and rated at post-heading stage. Intercrosses of these varieties, Anza/Yecora Rojo was not studied, permitted the following conclusions about the genes expressed in adult plants: Anza, one recessive gene; Glennson 81, two dominant genes; Ollanta, two genes, at least one is dominant; and Yecora Rojo; one dominant and one recessive gene, one of which is common with Ollanta. The resistance genes in these varieties, which expressed resistance in the seedling stage, were believed to be effective at the adult stage. Thus, seven resistance genes were identified in the four varieties. The genotypes were designated for the purposes of this study as follows: Anza, YrA YrH; Glennson 81, Yr9, YrJ, Ollanta YrL YrD; and Yecora Rojo, YrC YrD. It was recommended that these and other Yr genes be used as multiple gene complexes to increase durability of resistance to P. striiformis, an organism known to evolve virulence rapidly in field conditions. The demonstrated durability of Anza in California may be a result of its combination of resistance alleles at two loci.     

Genes for resistance to stripe rust in four spring wheat varieties

Summary Four spring wheat (Triticum aestivum L.) varieties differing in origin and reaction in the seedling stage to pathotype CDL-6 (extant in California) were intercrossed and examined in greenhouse conditions in F₁, F₂, and F₃ generations. Digenic and transgressive segregation was found in all crosses. The four varieties each had infection types (1 immune, 9 susceptible) and putative resistance genes as follows: Anza, IT 7, YrA; Glennson 81, IT 2, Yr9; Yecora Rojo, IT 6, YrC; and Ollanta, IT 4–6, YrL. Anza was classified as susceptible, Yecora Rojo and Ollanta as intermediate in seedling resistance, and Glennson 81 as resistant in the seedling stage.     

Leaf rust and stripe rust resistance genes transferred to common wheat from Triticum dicoccoides

Linked leaf rust and stripe rust resistance genes introduced from Triticum dicoccoides protected common wheat seedlings against a range of pathotypes of the respective pathogens. The genes were chromosomally mapped using monosomic and telosomic analyses, C-banding and RFLPs. The data indicated that an introgressed region is located on wheat chromosome arm 6BS. The introgressed region did not pair with the ‘Chinese Spring’ 6BS arm during meiosis possibly as a result of reduced homology, but appeared to pair with 6BS of W84-17 (57% of pollen mother cells) and ‘Avocet S’. The introgressed region had a very strong preferential pollen transmission (0.96–0.98) whereas its transmission through egg cells (0.41–0.66) varied with the genetic background of the heterozygote. Homozygous resistant plants had a normal phenotype, were fertile and produced plump seeds. Symbols Lr53 and Yr35 are proposed to designate the respective genes.     

普通小麦‘Holdfast’条锈病成株抗性QTL定位

Holdfast是来自英国的小麦品种,多年来一直保持良好的条锈病持久抗性。本研究目的是发掘Holdfast的条锈病成株抗性基因及其紧密连锁的分子标记,为小麦持久抗性品种选育提供材料和方法。利用铭贤169和Holdfast杂交后代重组自交系(recombinant inbred lines, RIL)群体,于2014—2015和2015—2016年度在甘肃甘谷、甘肃中梁和四川成都进行条锈病成株抗性鉴定,并统计最大严重度(maximum disease severity, MDS)。基于小麦660K SNP芯片和BSA(bulkedsegregantanalysis)技术初步确定抗病基因所在的染色体后,将目标区域的SNP标记转化为KASP(KompetitiveallelespecificPCR)标记,检测整个RIL群体,进行基因型分析。最后进行RIL群体条锈病成株抗性的QTL分析,在5AL和7AL染色体上发现了2个成株抗性QTL。5A染色体长臂上1个条锈病成株抗性QTL QYr.gaas-5AL,在所有环境下均存在,可解释6.5%～9.3%的表型变异; QYr.gaas-5AL位于标记Ax-109948955和Ax-108798241之间,连锁距离分别为0.5 cM和1.1 cM。在7A染色体长臂上定位到1个条锈病成株抗性QTL QYr.gaas-7AL,在2015年和2016年甘谷环境中均稳定存在,分别解释6.2%和7.3%的表型变异;QYr.gaas-7AL位于标记Ax-110361069和Ax-108759561之间,连锁距离分别为0.5 cM和0.7 cM。携带QYr.gaas-5AL和QYr.gaas-7AL抗病等位基因家系的MDS显著低于感病等位基因家系的MDS,表明QYr.gaas-5AL和QYr.gaas-7AL可有效降低条锈病严重度,可应用于小麦抗条锈育种。     

Suppression of stripe rust and leaf rust resistances in interspecific crosses of wheat

Stripe rust and leaf rust caused by Puccinia striiformis (Ps) Westend. and P. triticina (Pt) Eriks., respectively, are important foliar diseases of wheat worldwide. Breeding resistant wheat cultivars is the preferred strategy to control these diseases. Genes for resistance when introgressed from alien species or wheats of lower ploidy are frequently diluted effectiveness in the hexaploid wheat background or are completely suppressed. The objective of this study was to examine the expression of wheat stripe rust and leaf rust resistances derived from wild emmer wheat and Aegilops tauschii when combined in synthetic hexaploid lines. Eight amphidiploid wheat lines, synthesized by crossing five tetraploid wheats (AABB), viz. Triticum carthlicum var. darginicum, T. carthlicum var. fuligioscum, T. dicoccoides var. fuligioscum, T. durum with five lines of Ae. tauschii (DD), were evaluated in the seedling stage for resistance to five pathotypes of stripe rust caused by Ps and four pathotypes of leaf rust caused by Pt. Resistance in one or both parents was frequently suppressed in synthetic hexaploid lines, indicating the presence of suppressor genes in both Ae. tauschii and T. carthlicum var. darginicum. Specific suppression of resistance genes in the parental genotypes and to pathotypes of Ps and Pt were also observed. The presence and specificity of the suppressors for rust resistance obtained in this study provides useful knowledge for developing cultivars resistant to both rusts utilizing such genetic stocks in wheat breeding programs.     

Improving wheat stripe rust resistance in Central Asia and the Caucasus

Wheat is the most important cereal in Central Asia (Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan) and the Caucasus (Armenia, Azerbaijan and Georgia). Stripe rust, caused by Puccinia striiformis f. sp. tritici is considered the most important disease of wheat in Central Asia and the Caucasus (CAC). Although stripe rust has been present in the region for a long time, it has become a serious constraint to wheat production in the past 10 years. This is reflected by the occurrence of five epidemics of stripe rust in the CAC region since 1999, the most recent in 2010. Several wheat varieties occupying substantial areas are either susceptible to stripe rust or possess a low level of resistance. Information on the stripe rust pathogen in terms of prevalent races and epidemiology is not readily available. Furthermore, there is an insufficient understanding of effective stripe rust resistance genes in the region, and little is known about the resistance genes present in the commercial varieties and advanced breeding lines. The deployment of resistant varieties is further complicated by putative changes in virulence in the pathogen population in different parts of the CAC. Twenty four out of 49 improved wheat lines received through international nurseries or other exchange programs showed high levels of resistance to stripe rust to local pathogen populations in 2009. Fifteen of the 24 stripe rust resistant lines also possessed resistance to powdery mildew. It is anticipated that this germplasm will play an important role in developing stripe rust resistant wheat varieties either through direct adoption or using them as parents in breeding programs.     

小麦抗条锈病育种两种辩证法的比较研究

通过对简单杂交F6代和回交F6代的农艺性状和变异系数,以及对条锈病的发病株率、病情指数、一般配合力、特殊配合力比较分析,结果表明回交F6代在农艺性状如株高、穗型、穗长、穗数、穗粒数、千粒重等倾向轮回亲本;发病株率、病情指数明显低于简单杂交F6代,而特殊配合力则高于杂交F6代.由此在抗条锈育种上采用回交方法的效果较好.     

Leaf rust and stripe rust resistance genes Lr54 and Yr37 transferred to wheat from Aegilops kotschyi

The tendency of unpaired meiotic chromosomes to undergo centric misdivision was exploited to translocate leaf rust and stripe rust resistance genes from an Aegilops kotschyi addition chromosome to a group 2 chromosome of wheat. Monosomic and telosomic analyses showed that the translocation occurred to wheat chromosome arm 2DL. The introgressed region did not pair with the corresponding wheat 2DL telosome during meiosis suggesting that a whole arm may have been transferred. Female transmission of the resistance was about 55% whereas male transmission was strongly preferential (96%). The symbols Lr54 and Yr37 are proposed to designate the new resistance genes.