Developing a wheat germplasm collection with diverse pathogen and pest resistance.

Drs. Peter Dyck and Eric Kerber requested bread wheat (Triticum aestivum L.) and durum wheat (Triticum durum Desf.) germplasm from genetic banks across the world during the 1970s and 1980s. These diverse collections were screened at the time for leaf rust (Puccinia triticina Eriks.) and stem rust (Puccinia graminis Pers.:Pers. f. sp. tritici Eriks. & E. Henn.) resistance. In 2014, we initiated a project to identify promising lines from this material for leaf rust resistance by growing 200 lines in a leaf rust nursery. Resistant lines were harvested and retested in 2015, along with a new group of 200 lines. One hundred forty six were found to have resistance to leaf rust in the field in 2014 and/or 2015. These lines will be tested in 2016 for resistance to leaf rust, stem rust, stripe rust (Puccinia striiformis Westend.), Fusarium head blight (Fusarium graminearum Schwabe), and orange wheat blossom midge (Sitodiplosis mosellana Gehin). A new group of 200 lines from the Kyoto wheat collection will be screened in 2016 for leaf rust resistance, and resistant lines will be added to the germplasm collection for screening with multiple pests in 2017. We plan to generate a large and diverse collection of wheat germplasm, characterized for resistance to major pests of wheat in Canada. This should be an excellent resource for the development of resistance in wheat breeding programs. The genetic basis for resistance will be determined for many of the lines with the best levels of resistance to multiple pathogens.