Abstract
Key message: A new stem rust resistance geneSr59fromSecale cerealewas introgressed into wheat as a 2DS·2RL Robertsonian translocation. Abstract: Emerging new races of the wheat stem rust pathogen (Puccinia graminis f. sp. tritici), from Africa threaten global wheat (Triticum aestivum L.) production. To broaden the resistance spectrum of wheat to these widely virulent African races, additional resistance genes must be identified from all possible gene pools. From the screening of a collection of wheat–rye (Secale cereale L.) chromosome substitution lines developed at the Swedish University of Agricultural Sciences, we described the line ‘SLU238’ 2R (2D) as possessing resistance to many races of P. graminis f. sp. tritici, including the widely virulent race TTKSK (isolate synonym Ug99) from Africa. The breakage-fusion mechanism of univalent chromosomes was used to produce a new Robertsonian translocation: T2DS·2RL. Molecular marker analysis and stem rust seedling assays at multiple generations confirmed that the stem rust resistance from ‘SLU238’ is present on the rye chromosome arm 2RL. Line TA5094 (#101) was derived from ‘SLU238’ and was found to be homozygous for the T2DS·2RL translocation. The stem rust resistance gene on chromosome 2RL arm was designated as Sr59. Although introgressions of rye chromosome arms into wheat have most often been facilitated by irradiation, this study highlights the utility of the breakage-fusion mechanism for rye chromatin introgression. Sr59 provides an additional asset for wheat improvement to mitigate yield losses caused by stem rust.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1383-1392 |
| Number of pages | 10 |
| Journal | Theoretical and Applied Genetics |
| Volume | 129 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 1 2016 |
Bibliographical note
Funding Information:Mahbubjon Rahmatov was supported through Monsanto’s Beachell-Borlaug International Fellowship and the Swedish University of Agricultural Sciences. We also acknowledge support from the Lieberman-Okinow Endowment at the University of Minnesota (Brian Steffenson), the Durable Rust Resistance in Wheat Project administrated through Cornell University and supported by the Bill and Melinda Gates Foundation and UK Department for International Development (Matthew Rouse and Brian Steffenson); USDA-ARS Appropriated Project 5062-21220-021-00 (Matthew Rouse), and USDA-ARS National Plant Disease Recovery System (Matthew Rouse). We thank Sam Stoxen and Matthew Martin for their technical assistance, and Dr. Viktor Korzun and Dr. Marion Röder for providing the Xrems and Xgwm rye markers. Mention of trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product by the USDA, and does not imply its approval to the exclusion of other products and vendors that might also be suitable.
Publisher Copyright:
© 2016, Springer-Verlag Berlin Heidelberg.