Detection of Genomic Regions Associated with Resistance to Stem Rust in Russian Spring Wheat Varieties and Breeding Germplasm

Abstract

<jats:p>Stem rust caused by Puccinia graminis f. sp. tritici Eriks. is a dangerous disease of common wheat worldwide. Development and cultivation of the varieties with genetic resistance is one of the most effective and environmentally important ways for protection of wheat against fungal pathogens. Field phytopathological screening and genome-wide association study (GWAS) were used for assessment of the genetic diversity of a collection of spring wheat genotypes on stem rust resistance loci. The collection consisting of Russian varieties of spring wheat and introgression lines with alien genetic materials was evaluated over three seasons (2016, 2017 and 2018) for resistance to the native population of stem rust specific to the West Siberian region of Russia. The results indicate that most varieties displayed from moderate to high levels of susceptibility to P. graminis; 16% of genotypes had resistance or immune response. In total, 13,006 single-nucleotide polymorphism (SNP) markers obtained from the Infinium 15K array were used to perform genome-wide association analysis. GWAS detected 35 significant marker-trait associations (MTAs) with SNPs located on chromosomes 1A, 2A, 2B, 3B, 5A, 5B, 6A, 7A and 7B. The most significant associations were found on chromosomes 7A and 6A where known resistance genes Sr25 and Sr6Ai = 2 originated from Thinopyrum ssp. are located. Common wheat lines containing introgressed fragments from Triticum timopheevii and Triticum kiharae were found to carry Sr36 gene on 2B chromosome. It has been suggested that the quantitative trait loci (QTL) mapped to the chromosome 5BL may be new loci inherited from the T. timopheevii. It can be inferred that a number of Russian wheat varieties may contain the Sr17 gene, which does not currently provide effective protection against pathogen. This is the first report describing the results of analysis of the genetic factors conferring resistance of Russian spring wheat varieties to stem rust.</jats:p>

Identification and Validation of High LD Hotspot Genomic Regions Harboring Stem Rust Resistant Genes on 1B, 2A (Sr38), and 7B Chromosomes in Wheat

“…This set of eight SNPs located on 7B was highly LD and considered as a genomic region (Figure 6). Previous studies on bi-parental mapping populations and GWAS panel suggested the presence of Sr17 on 7B chromosome (Bansal et al, 2008;Yu et al, 2011Yu et al, , 2017Leonova et al, 2020). However, Sr17 is a virulent gene against QFCSC race.…”

Challenges and prospects for developing genetic resistance in common wheat against stem rust in Western Siberia

“…Путем сравнения расового состава образцов инфекции из Омска и Новосибирска выяснено, что первичной зоной формирования инокулюма P. graminis является Омская область (Сколотнева и др., 2020). Комплексное исследование культивируемых на территории Западной Сибири сортов мягкой пшеницы показало, что большинство из них восприимчивы к заболеванию, а остальные защищены небольшим количеством генов устойчивости: Sr25, Sr31, Sr36, Sr6Ai, Sr6Ai#2 (Shamanin et al, 2016;Leonova et al, 2020). При этом оценка коллекции мягкой яровой пшеницы Омского государственного аграрного университета на естественном инфекционном фоне лесостепи Западной Сибири продемонстрировала, что только 10 % сортов коллекции устойчивы к местному патогену.…”

Plant breeding is the food security basis in the Russian Federation

“…Molecular methods are currently used to accelerate selection in the stabilization of breeding material (Adonina et al, 2021), its homozygotization (Pershina et al, 2020), and so on. The raise of promising breeding material can be accelerated by removing the germplasm of wild species from the progeny of introgression hybrids (Leonova et al, 2020); thereby, fragments of alien genetic material can be reduced in the genome of a species to breed (Adonina et al, 2021). This process is aimed at the reduction of adverse effects of concomitant genetic material transferred with the target genes.…”