The challenge
Tackling a deadly disease
Oat crown rust also known as leaf rust is caused by the fungus Puccinia coronata f. sp. avenae and the most widespread and damaging disease of oat.
The disease occurs in oat growing regions of Australia and around the globe. It can significantly reduce grain yield or even cause entire crop losses if conditions are right for infection.
Chemical fungicides can be used to control oat crown rust however they can be costly and impact on the environment. The preferred method of control is to breed oat cultivars that are resistant to the disease.
CSIRO and GRDC have invested greatly in rust resistance research over many years, in particular providing genetic solutions in wheat and barley to reduce the impact of pests and diseases. We are now applying this knowledge and using state-of-the-art techniques in genomics, molecular biology and genetics to provide plant breeders with genetic sources of resistance to oat crown rust.
Our response
Building resistance through genetics
We are investigating genes that provide strong disease resistance in the crop and identifying the best combinations to provide the most effective and durable genetic control for Australian conditions.
To do this, we study the genetic pool of the Australian oat breeding germplasm and the biology of the pathogen. We focus on finding solutions to support decision making by the oat industry.
We welcome collaborations from across Australia and overseas. If you are interested in this work, please get in touch!
The results
Understanding global pathogen dynamics
For the first time, we have released a chromosome level genome assembly of Puccinia coronata f. sp. avenae and applied a population genomics approach to study the evolution of virulence in oat crown rust across North America. More recently, we have shifted this effort to examine the situation in Australia.
We are leading a comparative study with partners in Europe, Asia and South Africa and US to understand global pathogen dynamics and how those influence oat crown disease in Australia.
Related publications
Henningsen, E.C., Hewitt, T., Dugyala, S., Nazareno, E., Gilbert, E., Li, F., Kianian, S., Steffenson, B.J., Dodds, P.N., Sperschneider, J. and Figueroa, M., 2022. A chromosome-level, fully phased genome assembly of the oat crown rust fungus Puccinia coronata f. sp. avenae: a resource to enable comparative genomics in the cereal rusts. www.biorxiv.org/content/10.1101/2022.01.26.477636v1
Miller, ME., Nazareno, ES., Rottschaefer, SM., Riddle, J., Dos Santos Pereira, D., Li, F., Nguyen-Phuc, H., Henningsen, E., Persoons, A., Saunders, DGO., Stukenbrock, E., Dodds, PN., Kianian, SF., Figueroa, M. 2020. Increased virulence of Puccinia coronata f. sp. avenae populations through allele frequency changes at multiple putative Avr loci. PLoS Genetics 16(12): e1009291.
Figueroa, M., Dodds P.N., and Henningsen EC. Evolution of rust fungi – multiple solutions to one problem. 2020. Current Opinion in Plant Biology, 56: 20-27
Omidvar, V., Dugyala, S., Li, F., Rottschaefer, S.M., Miller, M.E., Ayliffe, M., Moscou, M.J., Kianian, S.F., Figueroa, M. 2018. Detection of race-specific resistance against Puccinia coronata f. sp. avenae in Brachypodium species. Phytopathology, 108(12):1443-54.
Miller, M.E. Zhang, Y., Omidvar, V., Sperschneider, J., Schwessinger, B., Raley, C., Palmer, J.M., Garnica, D., Upadhyayah, N., Rathjen, J., Taylor, J.M., Park, R.F., Dodds, P.N., Hirsch, C.D., Kianian, S.F., Figueroa, M. 2018. De novo assembly and phasing of dikaryotic genomes from two isolates of Puccinia coronata f. sp. avenae, the causal agent of oat crown rust. mBio, 9(1) e01650-17.