Genetic mapping of stem rust resistance gene Sr13 in tetraploid wheat (Triticum turgidum ssp. durum L.)

Abstract

Wheat stem rust caused by Puccinia graminis f. sp. tritici, can cause significant yield losses. To combat the disease breeders have deployed resistance genes both individually and in combinations to increase resistance durability. A new race, TTKSK (Ug99), identified in Uganda in 1999, is virulent on most of the resistance genes currently deployed, and is rapidly spreading to other regions of the world. It is therefore important to identify, map, and deploy resistance genes that are still effective against TTKSK. One of these resistance genes, Sr13, was previously assigned to the long arm of chromosome 6A, but its precise map location was not known. In this study, the genome location of Sr13 was determined in four tetraploid wheat (T. turgidum ssp. durum) mapping populations involving the TTKSK resistant varieties Kronos, Kofa, Medora and Sceptre. Our results showed that resistance was linked to common molecular markers in all four populations, suggesting that these durum lines carry the same resistance gene. Based on its chromosome location and infection types against different races of stem rust, this gene is postulated to be Sr13. Sr13 was mapped within a 1.2 to 2.8 cM interval (depending on the mapping population) between EST markers CD926040 and BE471213, which corresponds to a 285-kb region in rice chromosome 2, and a 3.1-Mb region in Brachypodium chromosome 3. These maps will be the foundation for developing high-density maps, identifying diagnostic markers, and positional cloning of Sr13.

Whole‐genome profiling and shotgun sequencing delivers an anchored, gene‐decorated, physical map assembly of bread wheat chromosome 6A

“…In this study, the comprehensive and integrated 6A physical map localized some genetic determinants to the corresponding physical map, and provided information required for the development of tightly linked genetic markers (Figure ). Such loci include one resistance QTL that is important against the wheat disease Fusarium head blight (Schmolke et al ., ; Holzapfel et al ., ), the stem rust resistance gene Sr13 (Dubcovsky et al ., ; Simons et al ., ), an anti‐xenosis gene against a new aphid biotype (Castro et al ., ) and QTLs involved in adult plant resistance to powdery mildew (Muranty et al ., ), as well as greater seedling vigor (Spielmeyer et al ., ). All of these QTLs/genes had already been genetically mapped to 6A; however, in the current study, only two corresponding gene intervals were successfully localized to the 6A physical map.…”

Discovery and molecular mapping of a new gene conferring resistance to stem rust, Sr53, derived from Aegilops geniculata and characterization of spontaneous translocation stocks with reduced alien chromatin

“…Gene pyramiding is facilitated by the ability to use molecular markers closely or completely linked to resistance genes. Molecular markers have been developed for numerous stem rust resistance genes, including: Sr2 (Spielmeyer et al 2003;Hayden et al 2004;Mago et al 2011), Sr6 (Tsilo et al 2009), Sr9a (Tsilo et al 2007), Sr13 (Admassu et al 2011;Simons et al 2011), Sr22 (Khan et al 2005;Olson et al 2010;Periyannan et al 2011), Sr24 (Mago et al 2005), Sr25 (Liu et al 2010), Sr26 (Mago et al 2005;Liu et al 2010), Sr30 (Hiebert et al 2010a), Sr31 (Das et al 2006;Weng et al 2007), Sr32 (Bariana et al 2001), Sr33 (Sambasivam et al 2008), Sr35 (Zhang et al 2010), Sr36 (Bariana et al 2001;Tsilo et al 2008), Sr39 (Gold et al 1999;Mago et al 2009;Niu et al 2011), Sr40 (Wu et al 2009), Sr45 (Sambasivam et al 2008), Sr50 (synonym SrR, Anugrahwati et al 2008), Sr51 (Liu et al 2011), Sr52 (Qi et al 2011), SrCad (Hiebert et al 2010b), and SrWeb (Hiebert et al 2010a). Recent progress on molecular marker development and improved donor sources should accelerate the pyramiding and deployment of cultivars with more durable resistance to stem rust.…”

Characterization of Stem Rust Resistance in Wheat Cultivar Gage

“…The recent development of molecular markers linked to stem rust resistance genes and the advancement of tools that allow marker scans of the whole genome facilitate genetic analysis and breeding in crop plants. The availability of microsatellite and other markers linked to wheat stem rust disease resistance, such as Sr6, Sr9a, Sr13, SrWeb, Sr22, Sr24, Sr1RS Amigo , Sr26, Sr28, Sr32, Sr33, Sr35, Sr36, Sr39, Sr40, Sr42, Sr44, Sr45, Sr47, Sr51, Sr52, Sr53, Sr54, Lr19/Sr25 (Prins et al, 2001; Mago et al, 2005; Tsilo et al, 2007; Tsilo et al, 2008; Tsilo et al, 2009; Wu et al, 2009; Olson et al, 2010a, b; Zhang et al, 2010; Hiebert et al, 2010; Niu et al, 2011; Qi et al, 2011; Liu et al, 2011a; Liu et al, 2011b; Simons et al, 2011; Ghazvini et al, 2012; Klindworth et al, 2012; Rouse et al, 2012; Ghazvini et al, 2013) aids identification of known genes for stem rust resistance. Furthermore, the use of genotyping‐by‐sequencing (GBS) technology to detect and score single‐nucleotide polymorphisms (SNPs) simultaneously (Deschamps et al, 2012) is particularly useful to investigate unknown stem rust resistance genes in wheat.…”