* Email: mi1@ualberta.ca

This study aimed to identify genomic regions controlling leaf rust, stripe rust, and leaf spotting resistance in a recombinant inbred line (RIL) population derived from two Canadian spring wheat cultivars, AAC Ryley and AAC Tenacious. The population, consisting of 279 RILs and the two parents, was genotyped using the 90K wheat Infinium iSelect SNP array.

Evaluation for disease resistance was conducted over multiple years and locations: leaf rust in Edmonton, Alberta (four years), Morden, Manitoba (two years); stripe rust in Edmonton, Alberta (three years), Creston, British Columbia (two years); and leaf spotting diseases in Edmonton, Alberta (three years). Preliminary QTL analysis utilizing 9015 polymorphic SNP markers and mean disease scores revealed 32 significant regions associated with resistance.

Thirteen regions were identified for leaf rust on chromosomes 1A, 3A, 3B, 4A, 4B, 4D, 5A, 5D, 7A, and 7D. Twelve regions were associated with stripe rust resistance on chromosomes 2B, 2D, 3A, 3D, 4A, 4D, 5A, and 7D, while five regions were linked to leaf spotting resistance on chromosomes 4A, 4D, 5A, 6D, and 7A.

The leaf rust QTLs explained 3-19% of the phenotypic variation, stripe rust QTLs explained 0.4-18%, and leaf spotting QTLs explained 4-12%. Notably, the QTL for leaf rust resistance on chromosome 7D is hypothesized to be the adult plant leaf rust resistance gene Lr34, and the QTL on 7A is likely the leaf rust resistance gene LrCen. Ongoing analysis seeks to determine the novelty of the other identified QTLs.