Genetic diversity of Puccinia striiformis from cereals in Alberta,Canada     

M. D. Holtz  K. Kumar  J. L. Zantinge  K. Xi 《Plant pathology》2014,63(2):415-424

Stripe rust of wheat caused by Puccinia striiformis f. sp. tritici has recently become a production problem on wheat in Alberta, Canada, and stripe rust of barley caused by P. striiformis f. sp. hordei occurs regularly. A total of 261 isolates of P. striiformis were collected from wheat, barley, Hordeum jubatum and triticale plants in Alberta, Canada from 2007 to 2012, and compared to isolates from other provinces and the USA. The genetic diversity of the pathogen was assessed using 11 simple sequence repeat (SSR) markers and by examining a length polymorphism in the ribosomal DNA (rDNA) intergenic spacer 1 (IGS1) region. A total of 28 SSR genotypes were detected within Alberta. The 13 genotypes common on wheat (P. striiformis f. sp. tritici) were distinct from the 15 genotypes common on barley (P. striiformis f. sp. hordei). Four SSR genotypes, two within each forma specialis, represented 85% of the isolates recovered. Genotypic diversity was low, population genetic analysis indicated a clonal structure, and the genotypes were widely dispersed. In both formae speciales, the dominant genotype varied between years. The second most common P. striiformis f. sp. hordei genotype was found to be more closely related to older P. striiformis f. sp. tritici genotypes from the USA than to other P. striiformis f. sp. hordei genotypes.  相似文献   

温度与条锈病菌双胁迫下小麦内参基因的选择     

王军娟  陶飞  安菲  徐向明  胡小平 《植物病理学报》2014,44(5):497-503

 选择合适的内参基因是采用实时定量PCR研究基因表达获得可信数据的关键。以小麦在条锈病菌及温度双因素胁迫为研究对象,采用实时荧光定量PCR评价了CDC、RLI、ACTIN和26S基因的表达情况,采用geNorm和NormFinder软件进行了比较分析。结果表明,小偃6号小麦在常温(15℃±1℃)未接种条锈病菌,以及接种条锈病菌并培育至花斑期分别在高温(20℃±1℃)、变温(20℃到15℃)条件处理中,基因RLI表达不稳定,基因ACTIN在常温条件下以及在条锈病菌及高温处理条件下的表达量相对稳定,但在变温条件下波动较大。表达最稳定的基因是26S,其次是CDC基因,它们可以作为小偃6号-CYR32-温度互作体系中基因表达实时荧光定量PCR研究的内参基因,26S和CDC是最佳内参基因组合。  相似文献   

Puccinia psidii in Queensland,Australia: disease symptoms,distribution and impact     

G. S. Pegg  F. R. Giblin  A. R. McTaggart  G. P. Guymer  H. Taylor  K. B. Ireland  R. G. Shivas  S. Perry 《Plant pathology》2014,63(5):1005-1021

Puccinia psidii has long been considered a significant threat to Australian plant industries and ecosystems. In April 2010, P. psidii was detected for the first time in Australia on the central coast of New South Wales (NSW). The fungus spread rapidly along the east coast and in December 2010 was found in Queensland (Qld) followed by Victoria a year later. Puccinia psidii was initially restricted to the southeastern part of Qld but spread as far north as Mossman. In Qld, 48 species of Myrtaceae are considered highly or extremely susceptible to the disease. The impact of P. psidii on individual trees and shrubs has ranged from minor leaf spots, foliage, stem and branch dieback to reduced fecundity. Tree death, as a result of repeated infection, has been recorded for Rhodomyrtus psidioides. Rust infection has also been recorded on flower buds, flowers and fruits of 28 host species. Morphological and molecular characteristics were used to confirm the identification of P. psidii from a range of Myrtaceae in Qld and compared with isolates from NSW and overseas. A reconstructed phylogeny based on the LSU and SSU regions of rDNA did not resolve the familial placement of P. psidii, but indicated that it does not belong to the Pucciniaceae. Uredo rangelii was found to be con‐specific with all isolates of P. psidii in morphology, ITS and LSU sequence data, and host range.  相似文献   

寡糖对向日葵锈菌侵染的影响   总被引：1，自引：0，他引：1  

李凌欣  裴旭  徐鑫  景岚 《中国油料作物学报》2011,33(1):62-65

为了明确寡糖对向日葵锈菌侵染的影响,在向日葵苗期用寡糖处理并接菌后对锈菌夏孢子的萌发率和侵入率以及气孔开闭进行了观察,并用甲苯胺蓝染色法对入侵位点酚类化合物的积累进行了检测。试验结果表明,与对照相比寡糖处理后锈菌夏孢子的萌发率和侵入率均显著降低,而气孔关闭率显著升高。同时,在接种后12 h时,大量的侵入位点产生了酚类化合物的积累,说明寡糖处理可以有效抑制向日葵锈菌的侵染。  相似文献   

条锈菌诱导上调表达的小麦腺苷甲硫氨酸脱羧酶（SAMDC）基因的克隆及其特征分析     

曾兴权  王长有  张宏  韦泽秀  刘新伦  王亚娟  吉万全 《麦类作物学报》2011,31(5):811-818

为了克隆条锈菌诱导上调表达的小麦腺苷甲硫氨酸脱羧酶（SAMDC）基因并研究其在小麦感病、抗病单株苗期抗条锈病防御反应中的作用,以大麦（Hordeum vulgareL.）SAMDC全长cDNA序列为信息探针,采用电子克隆、RACE（Rapid amplification of cDNA ends）和RT-PCR方法,从条锈菌（Puccinia stri-iformisf.sp.tritici）CYR32侵染的小麦（Triticum aestivumL.）抗条锈病新种质NR1121中分离出1个新的小麦SAMDC基因家族成员,命名为TaSAMDC2（GU016570）。TaSAMDC2基因cDNA序列全长2 003 bp,5′非翻译区区域和一个带有Poly（A）的3′非翻译区区域长分别为553和283 bp;该基因的开放阅读框为1 167 bp,编码388个氨基酸,编码的氨基酸序列包含酶原剪切位点和PEST结构域。基因组序列全长2 539bp,位于5′UTR存在一个526 bp长的内含子序列,内含子的剪切位点均符合真核生物GT-AG规则。同源序列分析表明,TaSAMDC2与来自大麦、水稻（Oryza sativaL.）、玉米（Zea maysL.）、一粒小麦（TriticummonococcumL.）4种植物SAMDC蛋白的相似性分别为95.0%、85.0%、80.0%和80.0%。半定量RT-PCR与实时荧光定量PCR分析表明,TaSAMDC2的表达受条锈菌诱导,小麦苗期经条锈菌侵染后,在抗病材料中,该基因于48 hpi上调表达至最高水平,而在感病材料中先下调、上调表达至最高水平明显滞后。结果提示,分离到的是一个条锈菌CYR32诱导后上调表达的小麦SAMDC基因,该基因可能参与了小麦的抗条锈病反应。  相似文献   

菊花白锈病抗性标准及人工离体接种鉴定方法的优化     

祝朋芳  赵妮拉齐丹刘娜  段玉玺 《中国农学通报》2011,27(13):149-152

为使菊花白锈病的抗性鉴定在可控条件下进行,本文将目测观察与显微镜检方法相结合,制定了菊花白锈病6级抗性鉴定标准,并优化了人工离体接种方法。结果表明,培养瓶内茎段扦插法、培养皿内平铺叶片法均可用于菊花白锈病的离体鉴定;培养瓶内茎段扦插法优于培养皿内平铺叶片法,是最佳的人工离体接种鉴定方法。该优化方法是评价菊花白锈病抗性的既安全又简单的接种方法。  相似文献   

The barley mutant emr2 shows enhanced resistance against several fungal leaf pathogens     

M. Jansen    U. Schaffrath 《Plant Breeding》2009,128(2):124-129

Homozygous mlo -barley plants are resistant to barley powdery mildew but hypersusceptible to the rice blast fungus Magnaporthe oryzae . A mutational analysis was performed in the barley back-cross line BCIngrid mlo5 which led to the identification of two mutants with enhanced capacity to resist infections by M. oryzae , referred to as enhanced M. oryzae resistance mutants emr1 and emr2 . Here, we report on the characterization of emr2 mutant plants which not only show an almost complete reduction in disease severity after inoculation with M. oryzae but are also resistant to the necrotrophic fungi Drechslera teres and Rhynchosporium secalis . Histological analysis revealed that resistance to M. oryzae was based mainly on the formation of papillae at sites of attempted penetration into epidermal cells. There was no progression of fungal growth into the mesophyll. Additionally, because of the presence of the mlo -allele, emr2 -plants retained resistance to powdery mildew. The emr2 -conditioned broad spectrum resistance was inherited as in a recessive manner. Monitoring of PR -gene expression and enzymatic activity of peroxidases revealed a constitutively activated defence in emr2 .  相似文献   

小麦条锈菌群体温度敏感性测定   总被引：1，自引：0，他引：1  

张静秋  刘博  陈万权  刘太国  高利 《植物病理学报》2013,43(1):88-90

小麦条锈病由小麦条锈菌(Puccinia striiformi Westend.)引起,该病害发生范围广、流行频率高、危害损失重.小麦条锈菌侵染与繁殖均需要较低温度,过去研究表明,条锈菌在夏季最热旬均温23℃以下地区才能越夏[1].近年调查研究发现,小麦条锈菌的越夏海拔下限明显降低,病菌在夏季最热旬的旬均温超过23℃的地区也能越夏.研究不同地区和不同年代小麦条锈菌群体对温度的敏感性,有助于了解温度对条锈菌群体进化的影响,明确在小麦条锈菌群体中是否产生了耐高温菌株,为小麦条锈病菌源区勘界、病害流行测报等提供科学依据.本文报道了对小麦条锈菌群体温度敏感性的初步研究结果. 1 材料与方法 1.1试验材料 1.1.1供试菌株采自全国不同流行区、不同年代的小麦条锈菌标样,经分离纯化后获得126个条锈菌菌株.  相似文献   

2010-2011年度我国小麦条锈菌生理专化研究   总被引：12，自引：0，他引：12  

刘太国  王保通  贾秋珍  章振羽  李强  曹世勤  彭云良  金社林  李明菊  刘博  高利  胡小平  陈万权 《麦类作物学报》2012,32(3):574-578

为给小麦条锈病预测及防控策略制定与实施提供科学依据,2010-2011年对采自全国14个省(市、自治区)的条锈菌标样进行了生理小种鉴定和分析。结果表明,在1 014份标样中,共监测到133个致病类型,其中CYR33出现频率达19.7%,与2009-2010年的23.7%相比略有下降,连续二年超过CYR32,居于首位;CYR32出现频率为18.1%(2009-2010年为21.6%),位居第二,主要分布在陕、甘、川地区。供试标样中还有44份被鉴定为贵农22致病类群,出现频率为4.3%,主要分布在四川、甘肃和云南三省,陕西、青海、山西、新疆、贵州和西藏等地亦有分布,应引起育种和推广部门的高度重视。  相似文献   

内生真菌对感染锈病黑麦草生长和生理的影响   总被引：2，自引：0，他引：2  

马敏芝  南志标 《草业学报》2011,20(6):150-156

在田间条件下对带内生真菌和不带内生真菌球道黑麦草品种被锈菌不同程度感染后的生长、光合特性和生理指标进行测定。结果表明,带内生真菌的植株无论感病轻重,其病叶损失率和植株矮化程度均显著低于不带内生真菌的植株(P<0.05)。并且在轻度和重度病株中,内生真菌可提高黑麦草叶片相对含水量、可溶性糖含量、叶绿素含量,净光合速率、蒸腾速率、气孔导度,叶内游离脯氨酸含量、超氧化物歧化酶与过氧化物酶的活性;同时有效地降低了丙二醛的含量,说明内生真菌的存在可提高寄主黑麦草在田间条件下的抗锈病能力。  相似文献