Genome wide association study to identify markers for stripe rust virulence and resistance in diverse Canadian wheat panels.

AWC contribution: $136,125

Start Date: April 1, 2021

End Date: March 31, 2024

Dr. Reem Aboukhaddour, AAFC-Lethbridge

Summary:

Stripe rust, caused by the fungal pathogen Puccinia striiformis f. sp. tritici (Pst) became an important wheat disease worldwide due to the emergence of new virulent races that can cause infection at higher temperatures than before, and have a wide virulence spectrum to defeat many of the known resistance (Yr) genes. In the funded (2018F181R), we investigated virulence changes in the Canadian stripe rust population from 1984 to 2017. Based on the virulence profile and defeated Yr genes, we found that Pst has remarkable changes in virulence twice in Canada, once around 2000 with remarkable defeat of Yr8 and Yr9, then around 2010 when Yr10 and Yr27 defeated. Currently, Pst in Canada remains avirulent on a very limited number of known genes: Yr1, Yr5, and Yr15. The rest of genes used in differential lines lost their capacity to differentiate between races and this makes it harder to track the pathogen incursions and changes. In this project, a genome-wide association study (GWAS) to identify virulence and resistance-associated markers from the Canadian stripe rust fungus and wheat genomes, respectively. The project is expected to generate useful tools to track rust changes in Canada and identify resistance in already genotyped elite lines.