我国小麦叶锈菌鉴别寄主抗性基因的推导

本研究用40个小麦叶锈菌的单孢培养物和21个已知Lr单基因系对我国新旧沿用的16个叶锈菌鉴别寄主的抗性基因进行了推导。结果指出这些鉴别寄主含有Lr1、3、13、14a和26等抗性基因。 基因分析表明,原用鉴别寄主鉴定小种的结果不能反映抗性基因信息,建议用已知Lr基因系(品种)作为鉴别寄主,以基因鉴定代替小种鉴定,本文讨论了基因稳定的复杂性和选用鉴别寄主问题。     

40个Lr基因在河北省抗病育种中的可用性研究

 本试验采用相对严重度的比较方法,对40个Lr基因系(品种)在河北省抗病育种中的可用性进行了研究。结果表明,Lr2d,Lr3等7个基因的相对严重度值高于82.35%,对叶锈病的抗性很差。Lr9,Lr19等7个基因抗性虽强,但能否转育在我国生产中应用不得而知。Lr1,Lr2a,Lr26等16个基因的相对严重度值为19 03-74.74%,在我国不少品种中已含有其中许多基因,它们的利用价值值得进一步研究。遗传背景对某些基因的表达有很大影响,在利用已知基因来推导品种中的未知基因以及在基因的转育时都要考虑到遗传背景的复杂性。基因组合可以提高对叶锈菌群体的抗性,应加强对基因间相互作用的研究。本研究根据已知基因在我国小麦品种中存在的情况,各基因的抗性效应,抗性类型以及对温度的敏感性等性状进行了综合分析,提出可考虑用Lr1,Lr2a,Lr2c,Lr3Bg,Lr10,Lr14ab,Lr15,Lr17,Lr21,Lr23,Lr26和Lr30等12个基因系作为叶锈菌的鉴别寄主,使我国叶锈菌生理分化研究能逐渐以基因鉴定代替小种鉴定。     

国际上小麦叶锈菌生理小种鉴别寄主及其小种命名方法

由于地理生态条件、叶锈菌群体结构、研究历史和研究方法等的差异,不同国家和地区采用相应的小麦叶锈菌鉴别寄主和小种命名方法。美洲、中国、欧洲、埃及、南非等国家和地区均采用以Thatcher为遗传背景的分别含有Lr1、Lr2 a、Lr2 c、Lr3、Lr9、Lr16、Lr24、Lr26、Lr3 ka、Lr11、Lr17和Lr30基因的近等基因系或单基因系作为小麦叶锈菌鉴别寄主,但附加的辅助鉴别品种不尽相同;澳大拉西亚和印度的鉴别寄主自成体系。这种格局不利于国家间研究结果的对比和交流。因此,建立一套国际通用鉴别体系实属当务之急。     

2019—2020年苏浙皖三省小麦叶锈菌群体的致病类型鉴定及毒性结构分析

为持续控制小麦叶锈病及促进小麦的抗叶锈病育种工作,2019—2020年自江苏、浙江和安徽3个省采集自然感叶锈病的小麦病叶,经分离获得小麦叶锈菌单孢分离物,利用43个小麦叶锈病鉴别寄主材料对其致病类型进行鉴定,并对其毒性结构进行分析。结果显示,从170份小麦叶锈菌单孢分离物中共鉴定出67个致病类型,主要致病类型为THS、SHJ、PHS和SHS,出现频率分别为8.8%、7.6%、5.9%和5.9%。江苏、浙江和安徽3个省的单孢分离物对携带抗叶锈基因Lr10、Lr12、Lr22a、Lr22b、Lr29、Lr33、Lr35和Lr36的鉴别寄主材料的苗期毒性频率均超过90.0%,而对携带抗叶锈基因Lr9、Lr24、Lr25、Lr28、Lr38、Lr40、Lr41、Lr42、Lr43和Lr13+3ka的鉴别寄主材料的苗期毒性频率均小于10.0%。卡方检验及Fisher精确检验显示,3个省小麦叶锈菌群体对抗叶锈基因Lr1、Lr2a、Lr3、Lr14b、Lr18、Lr21、Lr26、Lr27+31、Lr32和Lr37的毒力存在显著分化。浙江省小麦叶锈菌群体具有较少的毒性因子（4.73）和毒性值（600...     

生物间遗传学在防治河北省小麦叶锈病研究中的应用

作者应用生物间遗传学的观点和方法,对河北省的小麦品种与叶锈菌的相互作用进行了分析。供试的叶锈菌是来自河北省的177个标样,供试的28个小麦品种包括河北省的主要生产品种、区试品种(系)抗源和新鉴别寄主。用毒力频率法分析品种与叶锈菌群体的关系,有6个品种即鉴61、保麦2号、翼植88-5163、石86-2848、唐86-4043和百农3217表现较抗病。根据这6个品种对叶锈菌群体的反应、列出33种不同的毒性公式,在此基础上,根据若干品种对叶锈菌群体同时表现抵抗或感染计算抗性组合,为品种合理布局选择最佳组合,在小种鉴定方面,用新鉴别寄主对177个菌株的反应鉴定出频率在3.4%以上的小种8个,其中以V1,9-16和V1,9-12,14-16的频率较高,分别为13.6%和10.7%,也是近两年来北方冬麦区常出现的小种类型。在小种鉴定的基础上,根据28个品种与6个优势小种互作所出现的浸染型来推导品种和叶锈菌的基因型,共推导出7个抗性基因分散在不同的品种中。     

1999年我国小麦叶锈菌毒性监测

采用国际通用的小麦叶锈菌鉴别寄主和辅助鉴别寄主分析了来自1999年我国不同地区小麦叶锈菌的毒性基因,479个叶锈菌株共划分为162个毒性类型,其中23个为主要毒性类型.毒性类型中出现频率最高的为FHB、PHT、FHG、THT,它们对抗叶锈基因Lr2a、Lr2b、Lr3、Lr10、Lr14b、Lr16、 Lr26的平均毒性频率高于80%,而对Lr3ka、Lr25、Lr19、Lr24、Lr30、Lr15、Lr35的平均毒性频率低于30%;发现对Lr35有毒力的菌株,出现频率为1.04%;至今尚未发现对Lr38、Lr45抗性基因有毒力的菌株.研究同时发现,不同地区小麦叶锈菌的毒性类型不同,毒性频率存在一定的差异.Lr9、Lr15、Lr19、Lr24、Lr35、Lr38、Lr45为小麦抗叶锈育种可利用的有效抗病基因.     

Pavon76苗期抗小麦叶锈性基因的推导

 选用19个具不同毒性基因组合的小麦叶锈菌致病类型对墨西哥品种Pavon76进行了抗叶锈性基因的推导。通过与48个抗叶锈单/双基因系的反应型比较,鉴定出该品种中可能含有Lr1、Lr3、L410、L413、Lr14a、Lr34和LrB抗性基因。     

冬小麦品种北京837抗叶锈病基因的染色体定位研究

 1990~1993年间,引用中国春全套单体系列和抗叶锈病小麦近等基因系(或单基因系)为材料,采用单体遗传分析和基因推导相结合的方法,对冬小麦品种北京837抗叶锈病基因进行染色体定位研究,明确其对生理小种叶中1号的抗性系由分别位于染色体1B和6B上的两个显性互补基因所控制。位于1B染色体上的基因可能是Lr26,位于6B上的可能是Lr3a,二者可抵抗我国小麦叶锈菌群体中的部分生理小种(或毒性基因组合)。     

中国小麦条锈菌鉴别寄主维尔对条锈病的温敏抗性研究

维尔是中国小麦条锈菌重要鉴别寄主,通过潜育期变温处理对其进行温敏抗性检测和基因推导分析。本研究发现,维尔对小麦条锈菌流行小种条中32号的抗性表现为侵染型由常温下的高侵染型向高温下的低侵染型转变,侵染指数降低,呈现高温诱导抗条锈性;通过与已知的微效基因品系比较及方差分析,推测维尔对条中32号的温敏抗性可能是由2对高温诱导表达的温敏微效基因控制。建议将维尔作为温敏微效基因资源在抗病育种中利用,作为鉴别寄主用于小种鉴定时,要严格控制鉴定温度,不要超过18 ℃。     

小麦抗源Sw92抗叶锈病基因遗传及其分子标记

以小麦优异抗源Sw92为父本,感病小麦品种铭贤169为母本,杂交获得F1、F2和BC1代群体。采用我国叶锈菌优势小种PHT对双亲及其杂交世代进行接种鉴定。结果表明,小麦抗源Sw92对叶锈菌小种PHT的抗性系由一对隐性基因所控制。采用简单重复序列(SSR)技术对Sw92携带的抗性基因进行分子标记,共筛选了371对SSR引物,获得2个引物(WMC494、WMC737)可在抗/感池和双亲中扩增出多态性DNA片段。遗传连锁分析结果表明,该抗病基因位于小麦6BS上,与WMC494、WMC737标记的遗传距离分别为3.4cM和15.0cM,不同于6BS上的已知抗叶锈基因Lr36和Lr53,暂命名为LrSw92。     

Genetics of leaf rust resistance in spring wheat cultivars alsen and norm

ABSTRACT Alsen is a recently released spring wheat cultivar that has been widely grown in the United States because it has resistance to Fusarium head blight and leaf rust caused by Puccinia triticina. Norm is a high yielding wheat cultivar that has been very resistant to leaf rust since it was released. Alsen and Norm were genetically examined to determine the number and identity of the leaf rust resistance genes present in both wheats. The two cultivars were crossed with leaf rust susceptible cv. Thatcher and F(1) plants were backcrossed to Thatcher. Eighty one and seventy three BCF(1) of Thatcher times; Alsen and Thatcher x Norm respectively, were selfed to obtain BCF(2) families. The BCF(2) families were tested as seedlings with different isolates of P. triticina that differed for virulence to specific leaf rust resistance genes. The BCF(2) families that lacked seedling resistance were also tested as adult plants in greenhouse tests and in a field rust nursery plot. Segregation of BCF(2) families indicated that Alsen had seedling genes Lr2a, Lr10, and Lr23 and adult plant genes Lr13 and Lr34. Norm was determined to have seedling genes Lr1, Lr10, Lr16, and Lr23 and adult plant genes Lr13 and Lr34. The characterization of Lr23 in the segregating populations was complicated by the presence of a suppressor gene in Thatcher and the high temperature sensitivity of resistance expression for this gene. The effective leaf rust resistance in Alsen is due to the interaction of Lr13 and Lr23, with Lr34; and the effective leaf rust resistance in Norm is due to the interaction of Lr13, Lr16, and Lr23, with Lr34.     

Comparative Analysis of Indices in the Study of Virulence Diversity Between and Within Populations of Puccinia recondita f. sp. tritici in Israel

ABSTRACT Isolates of Puccinia recondita f. sp. tritici (n = 260) obtained from bread, durum, and wild emmer wheat leaf collections throughout Israel during 1993 to 1997 were analyzed for virulence on a set of wheat differentials. The overall frequency of virulence increased on differentials possessing resistance genes Lr1, Lr2a, Lr3, and Lr26 and decreased on Lr17, Lr21, and Lr30. Genes Lr9 and Lr24 were resistant, while Lr18 was susceptible (98% in 1996) to all tested leaf rust isolates and Lr10 and Lr23 were susceptible to more than 78% of the isolates. Diversity between populations (years) was assessed using Kosman's H(KB) (based on degrees of similarity among distinct phenotypes) and H(KDis) (based on frequencies of individual virulences) and Nei's and Rogers' distances. The greatest difference occurred between the 1993 and 1994 populations. Phenotypic diversity within each population (year) was analyzed using the Shannon's, Simpson's, and Kosman's indices. The highest diversity within years was recorded in 1994 and significantly increased from 1993 to 1994 for all indices. The variance in the diversity between populations can be only partially explained by differences between corresponding diversities within population. The comparative analysis of diversity between and within populations over the 5 years enabled a detailed study of changes in the pathogen population. The results show that the different measures do not yield the same rank order of diversity.     

我国25个小麦品种抗秆、叶锈基因初步分析

 本文采用基因推导法分析了我国25个重要小麦生产品种和抗源材料抗秆、叶锈菌的基因型。在供试的19个抗秆锈基因中,推导出了Sr5,Sr6、Sr7b、Sr8a、Sr9b、Sr31等6个基因,分布在20个小麦品种中;在14个抗叶锈基因中,推导出了Lr1、Lr2C、Lr10、Lr18、Lr26等5个基因,分布在11个小麦品种中。Sr5、Sr31、Lr2c和Lr26是供试品种的主要抗锈基因。     

江苏省重要小麦品种抗叶锈病和秆锈病基因初步分析

作者分别选用15个具不同毒性基因组合的叶锈菌系和10个具不同毒性基因组合的秆锈菌系推导分析了江苏省26个重要小麦品种(系)所携带的抗叶锈病和抗秆锈病基因。在供试的39个已知抗叶锈病基因(或基因组合)和44个已知抗秆锈病基因中,推导出了Lr1、Lr10、Lr13、Lr16、Lr26、Lt13 3Ka等6个抗叶锈病基因(或基因组合)和Sr5、Sr6、Sr7b、Sr8a、Sr9e、Sr10、Sr13、Sr14、Sr15、Sr17、Sr20、Sr23、Sr27、Sr28、Sr29、Sr31、SrTmp等17个抗秆锈病基因,以单基因或基因组合的形式分别分布在20和24个小麦品种(系)中,其中Lr16、Lr26和Sr5、Sr23、Sr31是供试材料的主要已知抗叶、秆锈病基因。初步发现一些品种(系)携带有Lr13和Sr31等已知持久抗锈基因(或基因组合)及不同于本研究所用的已知基因的未知基因。     

Genetic relationship between the adult plant resistance gene Lr12 and the complementary gene Lr31 for seedling resistance to leaf rust in common wheat

A resistant phenotype similar to that conferred in wheat by the complementary genes Lr27  +  Lr31 was produced in the progeny of intercrosses of cultivars carrying Lr27 and a line possessing Lr12 . This confirms that Lr12 is either completely linked with Lr31 or is the same gene. On the basis of these findings and that Lr31 is located on chromosome 4BS, it is concluded that Lr12 must also be located on 4BS. Adult-plant genetic tests confirm that the Australian wheat cultivar Timgalen carries Lr12 , and stocks with Lr12 alone were established from this cultivar.     

43个中国小麦品种(系)抗叶锈性研究

 选用12个墨西哥叶锈菌生理小种对43个中国小麦品种(系)所携带的抗叶锈病基因进行了推导,在25个品种(系)中推导出6个抗叶锈基因Lr1,Lr10,Lr13,Lr14a,Lr16和Lr26,9个品种(系)对本试验所使有的12个叶锈菌生理小种都表现感病反应,另有9个品种(系)携带未知的抗叶锈基因。在墨西哥2个地点进行的田间成株期抗叶锈性试验表明,12个品种(系)表现慢叶锈性,在将来的抗病育种中有一定的应用价值。     

Leaf rust resistance gene lr34 associated with nonsuppression of stem rust resistance in the wheat cultivar canthatch

ABSTRACT The common wheat cultivar Thatcher and the backcross derivative Canthatch are moderately or fully susceptible to several races of stem rust because of a suppressor on chromosome 7DL that inhibits the expression of the relevant resistance gene(s). The incorporation of leaf rust resistance gene Lr34 into 'Thatcher' is known to enhance stem rust resistance. The effect of this gene in a 'Canthatch' background and its relationship with the 7DL suppressor were determined by replacing chromosome 7D of 'Canthatch' with 7D of 'Chinese Spring', which possesses Lr34 on the short arm. 'Canthatch' nullisomic 7D was crossed with 'Chinese Spring', followed by a succession of backcrosses to the nullisomic recurrent parent. Homozygous resistant disomic and monosomic substitution lines were recovered that exhibited the same resistant reaction as that of 'Thatcher' possessing Lr34 and as that of 'Canthatch' nullisomic 7D, in which the 7DL suppressor is absent. The results indicate that, in 'Canthatch', Lr34 permits expression of resistance genes normally inhibited by the 7DL suppressor. Furthermore, it is likely that, in 'Thatcher' and 'Thatcher' back-cross derivatives, Lr34 inactivates the 7DL suppressor.     

116个小麦品种（系）抗叶锈基因Lr9-Lr26、Lr19-Lr20的复合PCR检测

[目的]建立简单、快速、有效的小麦抗叶锈基因复合PCR体系,从而提高分子标记辅助选择效率。[方法]以28个‘Thatcher’为背景的近等基因系和16个已知基因载体品系作为试材,测试了小麦抗叶锈病基因Lr9、Lr26、Lr19和Lr20的STS标记特异性,通过优化PCR反应体系和循环条件,构建了抗叶锈基因Lr9-Lr26和Lr19-Lr20的复合PCR检测体系。对116个小麦品种(系)所含有的抗叶锈病基因进行了分子检测。[结果]供试品种均不含有Lr9和Lr20,47个品种含有Lr26(基因频率为40.5%),‘中梁22’含有Lr19。经反复验证,Lr9-Lr26和Lr19-Lr20复合PCR技术检测结果可靠,且与上述单个分子标记检测结果一致。[结论]建立的Lr9-Lr26和Lr19-Lr20的复合PCR检测体系可以准确、稳定、高效地检测小麦抗叶锈基因Lr9、Lr26、Lr19和Lr20。