Location: Cereal Crops ResearchTitle: Identification of leaf rust resistance loci in a geographically diverse panel of wheat using high-resolution genome-wide association study
|KAUR, SHIVREET - North Dakota State University|
|GILL, HARSIMARDEEP - South Dakota State University|
|BREILAND, MATT - North Dakota State University|
|Kolmer, James - Jim|
|SEHGAL, SUNISH - South Dakota State University|
|GILL, UPINDER - North Dakota State University|
Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/16/2023
Publication Date: 2/1/2023
Citation: Kaur, S., Gill, H., Breiland, M., Kolmer, J.A., Gupta, R., Sehgal, S., Gill, U. 2023. Identification of leaf rust resistance loci in a geographically diverse panel of wheat using high-resolution genome-wide association study. Frontiers in Plant Science. https://doi.org/10.3389/fpls.2023.1090163.
Interpretive Summary: Global wheat production is continuously constrained by emergence of new and more virulent races of pathogens causing several economically important diseases. Among these, fungal pathogens are known to cause several important foliar diseases in wheat including three rusts: leaf rust, stem rust and stripe rust. Leaf rust alone is responsible for 3.25% yield loss in global wheat production annually. In this study a diversity panel of 365 bread wheat accessions selected from a worldwide population of landraces and cultivars was evaluated at the seedling stage against four prevalent races of fungus causing leaf rust. The resistant lines and putative novel genomic loci identified through phenotypic screenings and genome wide association study, respectively provide an avenue for developing leaf rust resistant cultivars in future.
Technical Abstract: Leaf rust, caused by Puccinia triticina (Pt) is among the most devastating diseases posing a significant threat to wheat production worldwide. The continuously evolving virulent Pt races in North America calls for exploring new sources of leaf rust resistance. A diversity panel of 365 bread wheat accessions selected from a worldwide population of landraces and cultivars was evaluated at the seedling stage against four prevalent Pt races (TDBJQ, TBBGS, MNPSD and, TNBJS). A wide distribution of seedling responses against the four Pt races was observed. Majority of the genotypes displayed a susceptible response with only 28 (9.8%), 59 (13.5%), 45 (12.5%) and 29 (8.1%) wheat accessions exhibiting a highly resistant response to TDBJQ, TBBGS, MNPSD and, TNBJS, respectively. A filtered set of 302,524 SNPs was used for conducting the preliminary GWAS analysis. The GWAS detected 27 marker trait associations (MTAs) of which 21 MTAs were found in the vicinity of known Lr genes or mapped to MTAs identified in previous studies. The remaining significant six MTAs (scaffold43155_283689, scaffold57495_4340875, caffold33098_3932746, scaffold57658-1_2072073, scaffold123808_1588140, and scaffold163140-5_613860) were considered loci that putatively harbor novel genomic regions for leaf rust resistance. The identified resistant lines and novel genomic loci provide an avenue for developing leaf rust resistant cultivars.