Abstract
Key message: Two stem rust resistance genes identified on chromosome arms 2BL and 6AL of the cultivated emmer wheat accession PI 193883 can be used for protecting modern varieties against Ug99 strains. Abstract: The wheat research community consistently strives to identify new genes that confer resistance to stem rust caused by the fungal pathogen Puccinia graminis f. sp. tritici Eriks & E. Henn (Pgt). In the current study, our objective was to identify and genetically characterize the stem rust resistance derived from the cultivated emmer accession PI 193883. A recombinant inbred line population developed from a cross between the susceptible durum wheat line Rusty and PI 193883 was genotyped and evaluated for reaction to Pgt races TTKSK, TRTTF, and TMLKC. Two QTLs conferring resistance were identified on chromosome arms 2BL (QSr.fcu-2B) and 6AL (QSr.fcu-6A). The stem rust resistance gene (Sr883-2B) underlying QSr.fcu-2B was recessive, and based on its physical location it is located proximal to the Sr9 region. QSr.fcu-6A was located in the Sr13 region, but PI 193883 is known to carry the susceptible haplotype S4 for Sr13, indicating that the gene underlying QSr.fcu-6A (Sr883-6A) is likely a new allele of Sr13 or a gene residing close to Sr13. Three IWGSC scaffold-based simple sequence repeat (SSR) and two SNP-based semi-thermal asymmetric reverse PCR (STARP) markers were developed for the Sr883-2B region, and one STARP marker was developed for Sr883-6A. Sr883-2B was epistatic to Sr883-6A for reaction to TTKSK and TRTTF, and the two genes had additive effects for TMLKC. These two genes and the markers developed in this research provide additional resources and tools for the improvement in stem rust resistance in durum and common wheat breeding programs.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 3177-3189 |
| Number of pages | 13 |
| Journal | Theoretical and Applied Genetics |
| Volume | 132 |
| Issue number | 11 |
| DOIs | |
| State | Published - Nov 1 2019 |
Bibliographical note
Funding Information:We thank Shiaoman Chao and Mary Osenga, at the USDA-ARS Small Grains Genotyping Lab at Fargo, ND, for assistance in genotyping the mapping population using the wheat 90 K SNP iSelect assays and Danielle Holmes for technical support in stem rust evaluations. This research was supported in part by funds to S. S. X. and M. N. R. provided through grants from the Bill & Melinda Gates Foundation and UK Department for International Development to Cornell University for the Durable Rust Resistance in Wheat (DRRW) and Delivering Genetic Gain in Wheat (DGGW) Projects. It was also funded by the US Department of Agriculture–Agriculture Research Service (USDA-ARS) Current Research Information System (CRIS) Projects Nos. 3060-21000-038-00D and 5062-21220-023-00-D.
Funding Information:
We thank Shiaoman Chao and Mary Osenga, at the USDA-ARS Small Grains Genotyping Lab at Fargo, ND, for assistance in genotyping the mapping population using the wheat 90?K SNP iSelect assays and Danielle Holmes for technical support in stem rust evaluations. This research was supported in part by funds to S. S. X. and M. N. R. provided through grants from the Bill & Melinda Gates Foundation and UK Department for International Development to Cornell University for the Durable Rust Resistance in Wheat (DRRW) and Delivering Genetic Gain in Wheat (DGGW) Projects. It was also funded by the US Department of Agriculture?Agriculture Research Service (USDA-ARS) Current Research Information System (CRIS) Projects Nos. 3060-21000-038-00D and 5062-21220-023-00-D.
Publisher Copyright:
© 2019, This is a U.S. government work and its text is not subject to copyright protection in the United States; however, its text may be subject to foreign copyright protection.
