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

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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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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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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