- Worldwide distribution. In Australia, New Caledonia, New Zealand.
- Serious fungal disease of Myrtaceae causing spots, distortions, defoliation, dieback and death depending on species. Major threat to native environments.
- Pustules (uredinia) on foliage and flowers, sometime purplish borders, producing masses of vivid yellow spores (urediniospores); occasionally, another thick-walled survival spore (teliospores) forms in the pustules on underside of leaves.
- Spread: spores on the wind; rain splash; on clothing, vehicles, animals, and the trade in wood and live plants.
- Biosecurity: difficult because wind dispersed, but regulation of movement of plant hosts important.
- Cultural control: regulate plant nurseries; avoid replanting susceptible species; hygiene measure (clothing, tools, vehicles) avoiding transfer of spores to healthy areas.
- Chemical control: strobilurin and sterol biosynthesis inhibitor (SBI) fungicides registered in Australia. Copper and mancozeb fungicides also likely effective.
Pacific Pests, Pathogens and Weeds - Online edition
Pacific Pests, Pathogens, Weeds & Pesticides
Myrtle rust (476)
Myrtle rust. It has other names based on the hosts infected, e.g., guava rust, eucalyptus rust, ohi'a rust.
Austropuccinia psidii; previous names are Puccina psidii, and Uredo rangelii. There are several strains or races that show different reactions on a range of host plants.
AUTHOR Grahame Jackson
Information from Myrtle rust (2015) Prime Fact. Department of Primary Industries. NSW Government. (https://www.dpi.nsw.gov.au/__data/assets/pdf_file/0011/573707/primefact-myrtle-rust.pdf); and Myrtle rust (undated) Department of Primary Industries. NSW, Australia. (https://www.dpi.nsw.gov.au/biosecurity/plant/insect-pests-and-plant-diseases/myrtle-rust); and Myrtle rust (2019) Business Queensland. Queensland Government. (https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/crop-growing/priority-pest-disease/myrtle-rust); and Invasive Species Council (undated) Environmental impacts of myrtle rust. (https://invasives.org.au/wp-content/uploads/2014/02/fs_myrtle_rust.pdf); and from CABI (2019) Austropuccinia psidii (myrtle rust). Crop Protection Compendium. (https://www.cabi.org/cpc/datasheet/45846). Photo 1 John Tann Myrtle rust on broad-leaves paperbark. Photos 2&4 Scott Nelson Paperbark tree: Myrtle rust. Photo 3 Forrest & Kim Starr, Starr Environmental. (File:Starr 080326-3705 Myrtus communis.jpg).
Produced with support from the Australian Centre for International Agricultural Research under project HORT/2016/185: Responding to emerging pest and disease threats to horticulture in the Pacific islands, implemented by the University of Queensland and the Secretariat of the Pacific Community.