Characterization of multiple rust resistance genes to design an optimal deployment strategy

• Term: Three years, beginning in 2016

• Status: Complete (CLICK HERE for the performance story)

• Funding Amount: $117,875

• Lead Researcher(s): Wentao Zhang (NRC)

• Funding Partners: Saskatchewan Ministry of Agriculture - Agriculture Development Fund (ADF)

Project Description

Rust, including stem rust, stripe rust and leaf rust, cause significant yield losses worldwide. Breeding new wheat varieties with genetic resistance is the most practical and effective approach to control these diseases. Durable rust resistance is desirable and is achieved by pyramiding multiple adult plant resistant genes (APRs, with minor effects) with race specific resistant genes (R genes, with major effects). This has long been recognized as a promising breeding strategy. To identify the most effective combinations of multiple rust resistant genes, we will attempt to characterize the genetics of the major APRs and specific R genes derived from a Parula/Thatcher cross, as well as their epistatic or additive interactions, to deliver the best gene combinations for rust resistance in Canadian wheat germplasm.

In this project, an available large DH population will be phenotyped with leaf, stem and stripe rusts by expert plant pathologists and breeders. It will be genotyped with 90K SNP chips. This will allow the precise and high-resolution mapping of known APRs with minor effects. A separate mapping approach will seek to identify novel APRs from this population. Efficient gene pyramids for multiple rust resistance will be identified.

Pre-breeding lines with novel APRs/or desirable multiple rust resistance will be generated. The relatively large size of the DH population will help us to target pre-breeding lines with new APRs or desirable multiple rust resistance. Pre-breeding lines adapted to the Thatcher genetic background will make these pre-breeding lines more readily accessible for our local breeding programs.