Project Leader

Dr Louise Shuey, Queensland Department of Agriculture and Fisheries




Entry of exotic strains of myrtle rust poses a further threat to Australian ecosystems. Preventing arrival of new strains is an ongoing, very-high priority in the Myrtle Rust Action Plan (MRAP, Objective 5.1). Our collaborators in the United States (Colorado State University) and Australia (University of Sydney) have developed molecular markers to distinguish exotic strains of myrtle rust. This project will validate these new diagnostics against the genotypic diversity of myrtle rust in Australia and South Africa (MRAP Objective 5.1.1), identified in a separate APBSF grant (PBSF0018), and strengthen the collaborative biosecurity network (MRAP 5.1.4, high priority).

Objectives and Impact


Our colleagues in the United States are developing DNA-based assays based on single nucleotide polymorphisms (SNPs) and colleagues at the University of Sydney have developed markers based on effector genes to distinguish different strains of myrtle rust.

  1. The markers developed by our colleagues will be amplified from approximately 100 single pustules of myrtle rust taken from a population in south-east Queensland (identified in PBSF0018).
  2. We will test these markers against one single pustule isolate of the population in South Africa (obtained in PBSF0018).

This will assess the robustness of diagnostic assays for their risk of producing false positives from variation in the Australian population of myrtle rust.


Improved detection of exotic myrtle rust strains through implementation and recommendation of DNA-based diagnostic tools (MRAP objective 5.1.1).

Engagement with researchers from South Africa and the United States as part of a global collaboration on myrtle rust (MRAP objective 5.1.4).

Impact We will deliver outcomes to policy, with diagnostic protocols recommended for biosecurity. Our validated diagnostic tool may identify exotic strains of myrtle rust and distinguish from the current population in Australia. Long-term exclusion benefits will flow from preventing entry of exotic strains of myrtle rust.