To enhance FHB screening capacity for spring and winter wheat breeders by testing lines submitted by breeders, to provide data for Fusarium damaged kernels (FDK) and deoxynivalenol (DON) for variety registration, post registration trials and breeding lines, and to provide phenotypic data for ongoing genetic studies.
Fusarium head blight (FHB) is the number one priority disease of wheat in Canada. It threatens all wheat growing areas by reducing crop yield, compromising end-use quality, and affecting food and feed safety through accumulation of mycotoxins such as deoxynivalenol (DON) in the grain. Fusarium graminearum is the primary causal agent of FHB in Canada. Management of FHB requires use of multiple strategies, as no single method provides complete control of FHB. Use of resistant cultivars is a critical component of an integrated FHB management system Resistance to FHB is complex and highly influenced by environment. Although numerous studies have been conducted to develop high-tech tools to increase selection efficiency for FHB resistance, the complexity of FHB is such that these tools have not been able to reliably select for FHB resistance. As a result phenotypic selection in the field is the best way to make advances in breeding for FHB resistance and to develop tools for future use.
The University of Manitoba has a well-established FHB screening nursery in Carman, MB that has been providing phenotypic data to breeders and researchers since 2001. Infrastructure and climatic conditions in this region are well suited to providing consistently reliable phenotypic data for FHB resistance. As a result, this nursery provides critical support for breeders to make advances in FHB resistance breeding. This project provided resources to expand the number of plots that could be tested for FHB reaction in 2018.
Hot, dry conditions in the Canadian Prairies meant that FHB was not a significant problem for most wheat producers in 2018. However, plant breeders must be able to reliably evaluate their breeding materials every year if they are to continue making progress for FHB resistance. The FHB nursery in Carman was able to provide excellent data for breeders to help them differentiate among susceptible and resistant lines. Disease levels were sufficiently high in all sections of the nursery and there was good separation of resistant and susceptible lines for all field traits measured (incidence, severity and visual rating index).
In total this project supported testing of 5070 plots from spring wheat breeders in western Canada for FHB disease incidence, severity and visual rating index. It also provided field data for 1745 plots in replicated trials for special projects such as mapping populations, B trials and genomic studies. Data for a Fusarium damaged kernels (FDK) and DON were collected for two winter wheat mapping populations. Support for three graduate student projects was provided through this project and multiple undergraduate and high school students were trained in field and lab techniques related to plant breeding and plant pathology.
What have we learned?
To continue to make progress in breeding for FHB resistance it is critical to have screening nurseries that can test breeding materials under conditions that can reliably produce disease epidemics and differentiate resistant and susceptible materials. Southern Manitoba is a “hotspot” for FHB infection and has the warm humid conditions required for optimum FHB infection. This, combined with the U of M Carman, MB misting system infrastructure that can provide the necessary humidity for infection, even under dry conditions, is the best location to generate phenotypic data for FHB.
Continued support for FHB nurseries is the best way to ensure progress in breeding for FHB resistance and to develop tools that will hasten section processes.