Races of Puccinia graminis f. sp. tritici with Combined Virulence to Sr13 and Sr9e in a Field Stem Rust Screening Nursery in Ethiopia

North American durum lines, selected for resistance to TTKSK (Ug99) and related races of Puccinia graminis f. sp. tritici in Kenya, became susceptible in Debre Zeit, Ethiopia, suggesting the presence of stem rust races that were virulent to the TTKSK-effective genes in durum. The objective of this study was to characterize races of P. graminis f. sp. tritici present in the Debre Zeit, Ethiopia stem rust nursery. Three races of P. graminis f. sp. tritici were identified from 34 isolates: JRCQC, TRTTF, and TTKSK. Both races JRCQC and TRTTF possess virulence on stem rust resistance genes Sr13 and Sr9e, which may explain why many TTKSK-resistant durum lines tested in Kenya became susceptible in Debre Zeit. The Sr9e-Sr13 virulence combination is of particular concern because these two genes constitute major components of stem rust resistance in North American durum cultivars. In addition to Sr9e and Sr13 virulence, race TRTTF is virulent to at least three stem rust resistance genes that are effective to race TTKSK, including Sr36, SrTmp, and resistance conferred by the 1AL.1RS rye translocation. Race TRTTF is the first known race with virulence to the stem rust resistance carried by the 1AL.1RS translocation, which represents one of the few effective genes against TTKSK in winter wheat cultivars in the United States. Durum entries exhibiting resistant to moderately susceptible infection response at the Debre Zeit nursery in 2009 were evaluated for reaction to races JRCQC, TRTTF, and TTKSK at the seedling stage. In all, 47 entries were resistant to the three races evaluated at the seedling stage, whereas 26 entries exhibited a susceptible reaction. These results suggest the presence of both major and adult plant resistance genes, which would be useful in durum-wheat-breeding programs. A thorough survey of virulence in the population of P. graminis f. sp. tritici in Ethiopia will allow characterization of the geographic distribution of the races identified in the Debre Zeit field nursery.

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Races of Puccinia graminis Identified in the United States During 2003

Plant Disease ◽

10.1094/pd-89-1125 ◽

2005 ◽

Vol 89 (10) ◽

pp. 1125-1127 ◽

Cited By ~ 28

Author(s):

Y. Jin

Keyword(s):

United States ◽

Resistance Genes ◽

Stem Rust ◽

Rust Resistance ◽

The United States ◽

Stem Rust Resistance ◽

Puccinia Graminis ◽

Wheat Stem Rust ◽

Stem Rust Resistance Genes ◽

Rust Resistance Genes

Stem rust of small grain cereals, caused by Puccinia graminis, is a major disease of wheat, barley, and oat. In order to effectively utilize stem rust resistance in the improvement of small grain cereals, it is necessary to monitor the virulence composition and dynamics in the stem rust population. Races of P. graminis from barberry, wheat, barley, and oat were surveyed across the United States during 2003. Aecial infections on barberry were primarily due to P. graminis f. sp. secalis, as inoculations using aeciospores failed to produce infection on wheat and oat. Race QFCS of P. graminis f. sp. tritici was the most common race identified from wheat and barley. Race QFCS has virulence on stem rust resistance genes Sr5, 8a, 9a, 9d, 9g, 10, 17, and 21 that are used for race identification. Race TTTT was identified in 2003. This race possesses virulence to all 16 stem rust resistance genes present in the wheat stem rust differentials and should be targeted in breeding for stem rust resistance. Race QFCN appeared to be a new race in the U.S. stem rust population. Races QCCJ and MCCF were identified, but at low frequencies. Seven races of P. graminis f. sp. avenae were identified from oat, and races NA-27, NA-29, and NA-67 were the predominant races. Race NA-76 was identified for the first time in the United States.

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Seedling Stage Resistance of Iranian Bread Wheat Germplasm to Race Ug99 of Puccinia graminis f. sp. tritici

Plant Disease ◽

10.1094/pdis-02-12-0138-re ◽

2013 ◽

Vol 97 (3) ◽

pp. 387-392 ◽

Cited By ~ 2

Author(s):

Mohsen Mohammadi ◽

Davoud Torkamaneh ◽

Mehran Patpour

Keyword(s):

Resistance Genes ◽

Stem Rust ◽

Rust Resistance ◽

Stem Rust Resistance ◽

Puccinia Graminis ◽

Wheat Cultivars ◽

Breeding Lines ◽

Wheat Germplasm ◽

Stem Rust Resistance Genes ◽

Rust Resistance Genes

Following emergence of Ug99, the new virulent race of Puccinia graminis f. sp. tritici in Africa, a global effort for identification and utilization of new sources of Ug99-resistant germplasm has been undertaken. In this study, we conducted replicated experiments to evaluate the resistance of Iranian wheat germplasm to the TTKSK lineage of the Ug99 race of P. graminis f. sp. tritici. We also evaluated for presence of stem rust resistance genes (i.e., Sr2, Sr24, Sr26, Sr38, Sr39, Sr31, and Sr1RSAmigo) in wheat cultivars and breeding lines widely cultivated in Iran. Our phenotyping data revealed high levels of susceptibility to Ug99 in Iranian bread wheat germplasm. Our genotyping data revealed that Iranian cultivars do not carry Sr24, Sr26, or Sr1RSAmigo. Only a few salt-tolerant cultivars and breeding lines tested positively for Sr2, Sr31, Sr38, or Sr39 markers. In conclusion, the genetic basis for resistance to Ug99 in Iranian wheat cultivars was found to be vulnerable. Acquiring knowledge about existing resistance genes and haplotypes in wheat cultivars and breeding lines will help breeders, cereal pathologists, and policy makers to select and pyramid effective stem rust resistance genes.

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Mutation to Wider Virulence in Puccinia graminis f. sp. tritici: Evidence for the Existence of Loci Which Allow the Fungus To Overcome Several Host Stem Rust Resistance Genes Simultaneously †

Applied and Environmental Microbiology ◽

10.1128/aem.57.8.2332-2336.1991 ◽

1991 ◽

Vol 57 (8) ◽

pp. 2332-2336 ◽

Cited By ~ 3

Author(s):

J. E. Gates ◽

W. Q. Loegering

Keyword(s):

Resistance Genes ◽

Stem Rust ◽

Rust Resistance ◽

Stem Rust Resistance ◽

Puccinia Graminis ◽

Stem Rust Resistance Genes ◽

Rust Resistance Genes

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Peer Review #1 of "Evaluation and identification of stem rust resistance genes Sr2, Sr24, Sr25, Sr26, Sr31 and Sr38 in wheat lines from Gansu Province in China (v0.1)"

10.7287/peerj.4146v0.1/reviews/1 ◽

2017 ◽

Author(s):

J Haile

Keyword(s):

Peer Review ◽

Resistance Genes ◽

Stem Rust ◽

Rust Resistance ◽

Stem Rust Resistance ◽

Gansu Province ◽

Stem Rust Resistance Genes ◽

Wheat Lines ◽

Rust Resistance Genes

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Identification of Winter Habit Bread Wheat Landraces in the National Small Grains Collection with Resistance to Emerging Stem Rust Pathogen Variants

Plant Disease ◽

10.1094/pdis-04-21-0743-re ◽

2021 ◽

Author(s):

Tyler Gordon ◽

Yue Jin ◽

Samuel Gale ◽

Matthew Rouse ◽

Samuel Stoxen ◽

...

Keyword(s):

Bread Wheat ◽

Resistance Genes ◽

Stem Rust ◽

Rust Resistance ◽

Stem Rust Resistance ◽

Field Nursery ◽

Small Grains ◽

Stem Rust Resistance Genes ◽

Landrace Accessions ◽

Rust Resistance Genes

Wheat stem rust caused by Puccinia graminis f. sp. tritici (Pgt) is a widespread and recurring threat to wheat production. Emerging Pgt variants are rapidly overcoming major gene resistance deployed in wheat cultivars and new sources of race-nonspecific resistance are urgently needed. The National Small Grains Collection (NSGC) contains thousands of wheat landrace accessions that may harbor unique and broadly effective sources of resistance to emerging Pgt variants. All NSGC available facultative and winter-habit bread wheat landraces were tested in a field nursery in St. Paul, MN against a bulk collection of six common U.S. Pgt races. Infection response and severity data were collected on 9,192 landrace accessions at the soft-dough stage and resistant accessions were derived from single spikes. Derived accessions were tested in St. Paul a second time to confirm resistance and in a field nursery in Njoro, Kenya against emerging races of Pgt with virulence to many known resistance genes including Sr24, Sr31, Sr38, and SrTmp. Accessions resistant in the St. Paul field were also tested at the seedling stage with up to 13 Pgt races, including TTKSK and TKTTF, and with 19 molecular markers linked with known stem rust resistance genes or genes associated with modern breeding practices. Forty-five accessions were resistant in both U.S. and Kenya field nurseries and lacked alleles linked with known stem rust resistance genes. Accessions with either moderate or strong resistance in the U.S. and Kenya field nurseries and with novel seedling resistance will be prioritized for further study.

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Molecular Marker Analysis of Stem Rust Resistance Genes in Some Iranian Wheat Genotypes

Cytology and Genetics ◽

10.3103/s0095452721050029 ◽

2021 ◽

Vol 55 (5) ◽

pp. 460-470

Author(s):

H. Javadi ◽

A. Dadkhodaie ◽

B. Heidari

Keyword(s):

Molecular Marker ◽

Resistance Genes ◽

Stem Rust ◽

Rust Resistance ◽

Stem Rust Resistance ◽

Wheat Genotypes ◽

Marker Analysis ◽

Molecular Marker Analysis ◽

Stem Rust Resistance Genes ◽

Rust Resistance Genes

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Mapping and characterization of wheat stem rust resistance genes SrTm5 and Sr60 from Triticum monococcum

Theoretical and Applied Genetics ◽

10.1007/s00122-017-3024-z ◽

2017 ◽

Vol 131 (3) ◽

pp. 625-635 ◽

Cited By ~ 10

Author(s):

Shisheng Chen ◽

Yan Guo ◽

Jordan Briggs ◽

Felix Dubach ◽

Shiaoman Chao ◽

...

Keyword(s):

Resistance Genes ◽

Stem Rust ◽

Rust Resistance ◽

Stem Rust Resistance ◽

Triticum Monococcum ◽

Wheat Stem Rust ◽

Stem Rust Resistance Genes ◽

Rust Resistance Genes

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Identification of stem rust resistance genes in wheat cultivars in China using molecular markers

PeerJ ◽

10.7717/peerj.4882 ◽

2018 ◽

Vol 6 ◽

pp. e4882 ◽

Cited By ~ 7

Author(s):

Xiaofeng Xu ◽

Depeng Yuan ◽

Dandan Li ◽

Yue Gao ◽

Ziyuan Wang ◽

...

Keyword(s):

Molecular Markers ◽

Resistance Genes ◽

Stem Rust ◽

Rust Resistance ◽

Genetic Material ◽

Stem Rust Resistance ◽

Wheat Cultivars ◽

Wheat Stem Rust ◽

Stem Rust Resistance Genes ◽

Rust Resistance Genes

Wheat stem rust caused by Puccinia graminis f. sp. tritici Eriks. & E. Henn. (Pgt), is a major disease that has been effectively controlled using resistance genes. The appearance and spread of Pgt races such as Ug99, TKTTF, and TTTTF, which are virulent to most stem rust-resistant genes currently deployed in wheat breeding programs, renewed the interest in breeding cultivars resistant to wheat stem rust. It is therefore important to investigate the levels of resistance or vulnerability of wheat cultivars to Pgt races. Resistance to Pgt races 21C3CTHQM, 34MKGQM, and 34C3RTGQM was evaluated in 136 Chinese wheat cultivars at the seedling stage. A total of 124 cultivars (91.2%) were resistant to the three races. Resistance genes Sr2, Sr24, Sr25, Sr26, Sr31, and Sr38 were analyzed using molecular markers closely linked to them, and 63 of the 136 wheat cultivars carried at least one of these genes: 21, 25, and 28 wheat cultivars likely carried Sr2, Sr31, and Sr38, respectively. Cultivars “Kehan 3” and “Jimai 22” likely carried Sr25. None of the cultivars carried Sr24 or Sr26. These cultivars with known stem rust resistance genes provide valuable genetic material for breeding resistant wheat cultivars.

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