TaMYB29: A Novel R2R3-MYB Transcription Factor Involved in Wheat Defense Against Stripe Rust

Members of the R2R3-MYB transcription factor superfamily have been implicated in plant development, improved disease resistance, and defense responses to several types of stresses. To study the function of TaMYB29 transcription factor—a member of the R2R3-MYB superfamily—in response to an avirulent race of stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst), we identified and cloned the TaMYB29 gene from wheat cultivar (cv.) AvS+Yr10 following infection with Pst. The TaMYB29 protein, comprising 261 amino acids, contains two highly conserved MYB domains. We first showed that TaMYB29 is a transcription factor, whose transcriptional levels are significantly induced by salicylic acid (SA), abscisic acid (ABA), jasmonic acid (JA), ethylene (ET), and Pst. The results showed that TaMYB29 is involved in the wheat response to stipe rust. The overexpression of the TaMYB29 gene resulted in the accumulation of reactive oxygen species (ROS) and pathogen-independent cell death in Nicotiana benthamiana leaves. The silencing of TaMYB29 gene in wheat cv. AvS+Yr10, containing the stripe rust resistance gene Yr10, promoted hyphae growth, significantly downregulated the expression of pathogenesis-related (PR) genes, and substantially reduced the wheat resistance to Pst compared with the non-silenced control. In addition, the accumulation of hydrogen peroxide (H2O2) significantly decreased, and the activity of catalase, an enzyme required for H2O2 scavenging, was elevated. Altogether, TaMYB29 positively regulates the defense response against stripe rust in wheat AvS+Yr10 by enhancing H2O2 accumulation, PR gene expression, and SA signaling pathway-induced cell death. These results provide new insights into the contribution of TaMYB29 to the defense response against rust pathogens in wheat.

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Emerging Yr26-Virulent Races of Puccinia striiformis f. tritici Are Threatening Wheat Production in the Sichuan Basin, China

Plant Disease ◽

10.1094/pdis-08-14-0865-re ◽

2015 ◽

Vol 99 (6) ◽

pp. 754-760 ◽

Cited By ~ 45

Author(s):

D. J. Han ◽

Q. L. Wang ◽

X. M. Chen ◽

Q. D. Zeng ◽

J. H. Wu ◽

...

Keyword(s):

Stripe Rust ◽

Sichuan Basin ◽

Puccinia Striiformis ◽

Field Tests ◽

Wheat Breeding ◽

Stripe Rust Resistance ◽

Breeding Lines ◽

Wheat Production ◽

Stripe Rust Resistance Gene ◽

The Sichuan Basin

Stripe rust, caused by Puccinia striiformis f. tritici, is one of the most destructive diseases of wheat in the world. The Sichuan Basin is one of the most important regions of wheat production and stripe rust epidemics in China. Stripe rust resistance gene Yr26 (the same gene as Yr24) has been widely used in wheat breeding programs and in many cultivars grown in this region since the gene was discovered in the early 1990s. Virulence to Yr26 has increased in frequency since its first detection in 2008. The objective of this study was to assess the vulnerability of the wheat cultivars and breeding lines in the Sichuan Basin to Yr26-virulent races. In total, 85 wheat accessions were tested with Yr26-avirulent races CYR32, CYR33, and Su11-4 and two Yr26-virulent races, V26/CM42 and V26/Gui22. DNA markers for Yr26 were used to determine the presence and absence of Yr26 in the wheat accessions. Of the 85 wheat accessions, only 5 were resistant and 19 susceptible to all races tested, and the remaining 61 were resistant to at least one or more races tested in seedling stage. In all, 65 (76.5%) accessions were susceptible to the emerging Yr26-virulent race V26/Gui22. In field tests, susceptible accessions increased from 31.8% in a nursery inoculated with predominant and Yr26-avirulent races to 61.2% in the nursery inoculated with the predominant races mixed with V26/Gui22. Based on the results of the molecular marker and race tests, 33 (38.8%) accessions were determined to have Yr26, showing that the Yr26 virulence is a major threat to wheat production in the Sichuan Basin and potentially in other regions of China.

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The R2R3-MYB transcription factor BnaMYB111L from rapeseed modulates reactive oxygen species accumulation and hypersensitive-like cell death

Plant Physiology and Biochemistry ◽

10.1016/j.plaphy.2019.12.027 ◽

2020 ◽

Vol 147 ◽

pp. 280-288

Author(s):

Lingfang Yao ◽

Bo Yang ◽

Baoshan Xian ◽

Bisi Chen ◽

Jingli Yan ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Cell Death ◽

Transcription Factor ◽

Reactive Oxygen ◽

Myb Transcription Factor ◽

Oxygen Species ◽

Reactive Oxygen Species Accumulation ◽

Species Accumulation ◽

R2r3 Myb

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Genetic and Molecular Mapping of Stripe Rust Resistance Gene in Wheat–Psathyrostachys huashanica Translocation Line H9020-1-6-8-3

Plant Disease ◽

10.1094/pdis-03-11-0204-re ◽

2012 ◽

Vol 96 (10) ◽

pp. 1482-1487 ◽

Cited By ~ 19

Author(s):

Qiang Li ◽

Jing Huang ◽

Lu Hou ◽

Pei Liu ◽

Jinxue Jing ◽

...

Keyword(s):

Resistance Gene ◽

Stripe Rust ◽

Rust Resistance ◽

Puccinia Striiformis ◽

Durable Resistance ◽

Rust Resistance Gene ◽

Stripe Rust Resistance ◽

Translocation Line ◽

Psathyrostachys Huashanica ◽

Stripe Rust Resistance Gene

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most important diseases of wheat worldwide. The best strategy to control stripe rust is to grow resistant cultivars, but only a few effective genes are available. The wheat accession H9020-1-6-8-3 is a translocation line previously developed from interspecific hybridization between wheat genotype 7182 and Psathyrostachys huashanica, and is resistant to most Chinese Puccinia striiformis f. sp. tritici races. To identify the resistance genes in the translocation line, H9020-1-6-8-3 was crossed with susceptible genotype Mingxian 169, and seedlings of parents and F1, F2, and F3 progenies were tested with prevalent Chinese P. striiformis f. sp. tritici races CYR32 and CYR33 under controlled greenhouse conditions. The genetic results indicated that two single dominant genes in H9020-1-6-8-3 confer resistance to CYR32 and CYR33, respectively. The gene for resistance to CYR33 was temporarily designated as YrH9020. Six simple-sequence repeat markers were used to map the resistance gene to the short arm of wheat chromosome 2D, using 329 F2 plants tested with CYR33 in the greenhouse. The genetic distances of the two closest flanking markers, Xgwm261 and Xgwm455, were 4.4 and 5.8 centimorgans, respectively. Disease assessments and polymorphic tests of the flanking markers among the Psathyrostachys huashanica line and wheat lines 7182, H9020-1-6-8-3, and Mingxian169 suggested that the resistance gene YrH9020 in H9020-1-6-8-3 was originally from P. huashanica. The exotic stripe rust resistance gene and linked molecular markers should be useful for pyramiding with other genes to develop wheat cultivars with high-level and durable resistance to stripe rust.

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Molecular Mapping of Stripe Rust Resistance Gene Yr81 in a Common Wheat Landrace Aus27430

Plant Disease ◽

10.1094/pdis-06-18-1055-re ◽

2019 ◽

Vol 103 (6) ◽

pp. 1166-1171 ◽

Cited By ~ 14

Author(s):

Mesfin Gessese ◽

Harbans Bariana ◽

Debbie Wong ◽

Matthew Hayden ◽

Urmil Bansal

Keyword(s):

Stripe Rust ◽

Rust Resistance ◽

Molecular Mapping ◽

Puccinia Striiformis ◽

Stripe Rust Resistance ◽

Chromosomal Assignment ◽

Resistance Locus ◽

Sources Of Resistance ◽

Stripe Rust Resistance Gene ◽

Ril Population

The deployment of diverse sources of resistance in new cultivars underpins durable control of rust diseases. Aus27430 exhibited a moderate level of stripe rust resistance against Puccinia striiformis f. sp. tritici (Pst) pathotypes currently prevalent in Australia. Aus27430 was crossed with the susceptible parent Avocet S (AvS) and subsequent filial generations were raised. Monogenic segregation observed among Aus27430/AvS F3 families was confirmed through stripe rust screening of an F6 recombinant inbred line (RIL) population, and the resistance locus was temporarily named YrAW5. Selective genotyping using an Illumina iSelect 90K wheat SNP bead chip array located YrAW5 in chromosome 6A. Genetic mapping of the RIL population with linked 90K SNPs that were converted into PCR-based marker assays, as well as SSR markers previously mapped to chromosome 6A, confirmed the chromosomal assignment for YrAW5. Comparative analysis of other stripe rust resistance genes located in chromosome 6A led to the formal designation of YrAW5 as Yr81. Tests with a marker linked with Yr18 also demonstrated the presence of this gene in Aus27430. Yr18 interacted with Yr81 to produce stripe rust responses lower than those produced by RILs carrying these genes individually. Although gwm459 showed higher recombination with Yr81 compared with the other flanking marker KASP_3077, it amplified the AvS allele in 80 cultivars, whereas KASP_3077 amplified AvS allele in 67 cultivars. Both markers can be used in marker-assisted selection after confirming parental polymorphism.

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Genetic Relationship of Stripe Rust Resistance Genes Yr34 and Yr48 in Wheat and Identification of Linked KASP Markers

Plant Disease ◽

10.1094/pdis-08-17-1144-re ◽

2018 ◽

Vol 102 (2) ◽

pp. 413-420 ◽

Cited By ~ 15

Author(s):

N. Qureshi ◽

H. S. Bariana ◽

P. Zhang ◽

R. McIntosh ◽

U. K. Bansal ◽

...

Keyword(s):

Resistance Gene ◽

Stripe Rust ◽

Rust Resistance ◽

Puccinia Striiformis ◽

Rust Resistance Gene ◽

Stripe Rust Resistance ◽

Adult Plant ◽

Wheat Genotypes ◽

Stripe Rust Resistance Gene ◽

Australian Continent

The Australian continent was free from wheat stripe rust caused by Puccinia striiformis f. sp. tritici until exotic incursions occurred in 1979 and 2002. The 2002 incursion enabled the identification of a new stripe rust resistance gene (Yr34) in the advanced breeding line WAWHT2046. In this study, we developed and validated markers closely linked with Yr34, which is located in the distal region in the long arm of chromosome 5A. Four kompetitive allele-specific polymerase chain reaction (KASP) and three sequence-tagged site (STS) markers derived from the International Wheat Genome Sequencing Consortium RefSeq v1.0 scaffold-77836 cosegregated with Yr34. Markers sun711, sun712, sun725, sunKASP_109, and sunKASP_112 were shown to be suitable for marker-assisted selection in a validation panel of 71 Australian spring wheat genotypes, with the exception of cultivar Orion that carried the Yr34-linked alleles for sunKASP_109 and sunKASP_112. Markers previously reported to be linked with adult plant stripe rust resistance gene Yr48 also cosegregated with Yr34. Wheat genotypes carrying Yr34 and Yr48 produced identical haplotypes for the Yr34-linked markers identified in this study and those previously reported to be linked with Yr48. Phenotypic testing of genotypes carrying Yr34 and Yr48 showed that both genes conferred similar seedling responses to pre-2002 and post-2002 P. striiformis f. sp. tritici pathotypes. Further testing of 600 F2 plants from a cross between WAWHT2046 and RIL143 (Yr48) with P. striiformis f. sp. tritici pathotype 134 E16A+Yr17+Yr27+ failed to reveal any susceptible segregants. Our results strongly suggest that Yr34 and Yr48 are the same gene, and that Yr48 should be considered a synonym of Yr34.

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Molecular mapping of stripe rust resistance gene YrH922 in a derivative of wheat (Triticum aestivum)–Psathyrostachys huashanica

Crop and Pasture Science ◽

10.1071/cp19317 ◽

2019 ◽

Vol 70 (11) ◽

pp. 939

Author(s):

Zhengwu Fang ◽

Cai Sun ◽

Tao Lu ◽

Zhi Xu ◽

Wendi Huang ◽

...

Keyword(s):

Triticum Aestivum ◽

Resistance Gene ◽

Stripe Rust ◽

Rust Resistance ◽

Puccinia Striiformis ◽

Dominant Gene ◽

Rust Resistance Gene ◽

Stripe Rust Resistance ◽

Psathyrostachys Huashanica ◽

Stripe Rust Resistance Gene

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici Erikss (Pst), is one of the most damaging diseases in common wheat (Triticum aestivum L.) globally. Breeding for genetic resistance is the most effective, economical and ecologically sustainable method to control the disease. The wheat line H922-9-12, developed from a cross between Psathyrostachys huashanica Keng and T. aestivum, was highly resistant to nine Pst races in tests at the seedling stage. To characterise and map the stripe rust resistance gene(s) in H922-9-12, segregating populations were developed by crossing H922-9-12 with the susceptible cultivar Mingxian 169. When tested with Pst race CYR34, the stripe rust resistance in H922-9-12 was shown to be controlled by a single dominant gene, provisionally designated YrH922. A linkage map was constructed with five simple sequence repeat, six expressed sequence tag (EST) and two sequence-related amplified polymorphism markers. YrH922 was located on chromosome 3BL and was 2.7 and 3.4 cM proximal to EST-STS (sequence-tagged site) markers BE517923 and BE471045, respectively. The flanking marker BE517923 in marker-assisted selection for the gene can be used to improve stripe rust resistance on breeding programs.

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Association Analysis Identifies New Loci for Resistance to Chinese Yr26-Virulent Races of the Stripe Rust Pathogen in a Diverse Panel of Wheat Germplasm

Plant Disease ◽

10.1094/pdis-12-19-2663-re ◽

2020 ◽

Vol 104 (6) ◽

pp. 1751-1762 ◽

Cited By ~ 3

Author(s):

Jianhui Wu ◽

Xiaoting Wang ◽

Nan Chen ◽

Rui Yu ◽

Shizhou Yu ◽

...

Keyword(s):

Stripe Rust ◽

Rust Resistance ◽

Puccinia Striiformis ◽

Snp Array ◽

Stripe Rust Resistance ◽

Phenotypic Effect ◽

Breeding Programs ◽

Stripe Rust Resistance Gene ◽

Trait Locus ◽

Yr Genes

Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is one of the most destructive fungal diseases of wheat worldwide. The expanding Yr26-virulent Pst race (V26) group overcomes almost all currently deployed resistance genes in China and has continued to accumulate new virulence. Investigating the genetic architecture of stripe rust resistance in common wheat is an important basis for a successful utilization of resistance in breeding programs. A panel of 410 exotic wheat germplasms was used for characterizing new stripe rust resistance loci. This panel was genotyped using high-density wheat 660K single-nucleotide polymorphism (SNP) array, and phenotypic evaluation of seedlings for stripe rust resistance was performed using multiple Pst races. Thirty-five loci conferring resistance were identified through genome-wide association mapping, and explained phenotypic variances ranged from 53 to 75%. Of these, 14 were colocated in the proximity of the known loci, including cataloged Yr genes Yr9, Yr10, Yr26, Yr33, Yr47, Yr56, Yr57, Yr64, Yr67, Yr72, and Yr81 and three temporarily designated as YrCen, YrNP63, and YrRC detected in our quantitative trait locus (QTL) mapping studies. Seven of them (Yr9, Yr10, Yr24/26, Yr81, YrCEN, YrNP63, and YrRC) were confirmed by molecular detection or genetic analysis. New loci that were identified to be different from reported Yr genes need further confirmation. Nine QTL with significantly large phenotypic effect on resistance to all tested races were considered as major loci for effective resistance. The identified loci enrich our stripe rust resistance gene pool, and the linked SNPs should be useful for marker-assisted selection in breeding programs.

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Microtubule Polymerization Functions in Hypersensitive Response and Accumulation of H2O2in Wheat Induced by the Stripe Rust

BioMed Research International ◽

10.1155/2016/7830768 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7

Author(s):

Juan Wang ◽

Yang Wang ◽

Xinjie Liu ◽

Yuanliu Xu ◽

Qing Ma

Keyword(s):

Cell Death ◽

Stripe Rust ◽

Hypersensitive Response ◽

Puccinia Striiformis ◽

Rust Fungus ◽

Defense Responses ◽

Microtubule Inhibitor ◽

Hypersensitive Cell Death ◽

Wheat Leaves ◽

Plant Cytoskeleton

The plant cytoskeleton, including microtubules and microfilaments, is one of the important factors in determining the polarity of cell division and growth, as well as the interaction of plants with invading pathogens. In defense responses of wheat against the stripe rust (Puccinia striiformisf. sp.tritici) infection, hypersensitive response is the most crucial event to prevent the spread of pathogens. In order to reveal the effect of microtubules on the hypersensitive cell death and H2O2accumulation in the interaction of wheat (Triticum aestivum) cv. Suwon 11 with an incompatible race, CYR23, wheat leaves were treated with microtubule inhibitor, oryzalin, before inoculation. The results showed that the frequency of infection sites with hypersensitive response occurrence was significantly reduced, and hypersensitive cell death in wheat leaves was suppressed compared to the control. In addition, the frequency and the incidence of infected cells with H2O2accumulation were also reduced after the treatment with oryzalin. Those results indicated that microtubules are related to hypersensitive response and H2O2accumulation in wheat induced by the stripe rust, and depolymerization of microtubules reduces the resistance of plants to pathogen infection in incompatible interaction, suggesting that microtubules play a potential role in the expression of resistance of wheat against the stripe rust fungus.

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