Email: Curt.McCartney@umanitoba.ca, singhk1@myumanitoba.ca

Canada is the sixth largest wheat producer in world with Western Canada responsible for over 90% of Canadian wheat production. Abiotic and biotic factors limit wheat production with rust diseases (caused by Puccinia spp.) being one of the main biotic constraints. Leaf rust (also known as brown rust), caused by the fungus Puccinia triticina (Pt), is a prevalent rust disease in North America and is a Priority One disease in Western Canadian wheat breeding.

Leaf rust is controlled with conjunction of multiple strategies of which genetic resistance is most reliable and desirable method. The objective of this study is to identify leaf rust resistance genes in a doubled haploid winter wheat population developed by crossing Emerson (susceptible to leaf rust) and W538 (resistant to leaf rust). Phenotypic data was collected at the seedling stage from a greenhouse trial located in AAFC Morden, and field trials located in Winnipeg and Morden for collecting adult plant resistance data in summer (June-July) 2024.

The genotypic data based on single nucleotide polymorphism (SNP) markers will be collected via a 25K Infinium SNP array developed by SGS TraitGenetics. Linkage and QTL analysis based on the phenotypic and the genotypic data will indicate markers that are closely linked with leaf rust resistance and further studies will follow to develop KASP markers from the markers of interest.

The results of this study will broaden our understanding of leaf rust resistance in Western Canadian winter wheat.