Development of SCAR markers for identification of stem rust resistance gene Sr31 in the homozygous or heterozygous condition in bread wheat

Abstract

The stem rust resistance gene Sr31, transferred from rye (Secale cereale) into wheat (Triticum aestivum L.) imparts resistance to all the virulent pathotypes of stem rust (Puccinia graminis f. sp. tritici) found in India. Wheat genotypes including carriers and non-carriers of the Sr31 gene were analysed using arbitrary primed polymerase chain reaction (AP-PCR). AP-PCR markers viz. SS30.2 580(H) associated with the Sr31 gene and SS26.1 1100 associated with the allele for susceptibility were identified. Linkage between the markers and phenotypes was confirmed by analysing an F 2 population obtained from a cross between a resistant and a susceptible genotype. The markers were tightly linked to the respective alleles. Both the AP-PCR markers were converted into sequence characterized amplified region (SCAR) markers, viz. SCSS30.2 576 and SCSS26.1 1100 respectively. The markers were validated in two more segregating populations and 49 wheat genotypes. Using both markers it was possible to distinguish the homozygous from the heterozygous carriers of the Sr31 gene in the F 2 generation. The markers developed in this study can be used for pyramiding of the Sr31 gene with other rust resistance genes and in marker-assisted selection.

Seedling Resistance to Stem Rust and Molecular Marker Analysis of Resistance Genes in Wheat Cultivars of Yunnan, China

“…tritici ) found in China. The SCSS30.2 576 marker amplified an expected PCR product of approximately 576 bp [26] in the positive control Sr31 (Fig 4). It acted as a specific marker with no product generated in lines that do not carry Sr31 .…”

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.…”

Genetic analysis of rust resistance genes in global wheat cultivars: an overview

“…Moreover, only one spring wheat, Trizo, was found to carry the Lr20 gene and was recommended for release as a variety in the Northwestern, Central, and Central Chernozem regions of Russia [39,194,]. Lr53 [68], Lr54 [69], and Lr56 [161] have been recorded in spring wheat cultivars from Chinese origin and are closely linked with Yr35, Yr37, and Yr38, respectively, and Lr62 [162] was recorded in California wheat cultivars linked with the stripe rust resistance gene Yr42. The adult-plant leaf rust resistance genes Lr34, Lr46, Lr67 and Lr68 have been identified in the Brazilian wheat cultivar Toropi [39].…”