Myrtle Rust spreads in Australia

On Friday 17 July, MPI suspended the import health standards for Myrtaceae cut flowers and foliage from Australia. This means that importation of some species of cut flowers and foliage from Australia will no longer be possible. This suspension is due to a significant change in the distribution of myrtle rust in Australia.

Myrtle rust is a devastating plant disease caused by the fungus Puccinia psidii sensu lato (s.l.) complex (including Uredo rangelii), that affects a wide range of plants in the Myrtaceae family. Symptoms begin as golden yellow powdery patches on leaves and stems, which expand leading to necrotic tissue and deformed stems which can cause die back in severe infections. Floral buds can also be affected (MAF, 2011). Myrtle rust is a regulated pest of significant concern to New Zealand. If introduced it has the potential to establish in New Zealand, causing significant economic, environmental and socio-cultural impacts. Potential economic impacts include Eucalyptus forestry, feijoa orchards, manuka honey production and nurseries producing Myrtaceae species.  Environmental and socio-economic impacts include infections on iconic native (including pohutukawa, rata, ramarama), and ornamental species (MAF, 2011).

Myrtle rust has previously been reported in the Australian states of New South Wales, Queensland, Victoria, and Tasmania. Importation of cut flowers and foliage of species in the Myrtaceae family is currently prohibited from these states. A significant detection of myrtle rust has now been reported from the Northern Territory (ABC News, 2015; NTDPIF, 2015).

Suspending importation of cut flowers and foliage of Myrtaceae species from Australia (by extending the existing suspension on imports from New South Wales, Queensland, Victoria, and Tasmania) is an emergency measure which is consistent with the principles of the International Plant Protection Convention (Article VII, paragraphs 1(a), 2(g), and 2(h)). If the detection of myrtle rust in Australia is able to be officially eradicated, then the IHS can be amended to re-instate the previous phytosanitary measures that applied to the pathway.

The suspension is implemented through an urgent amendment to the import health standard for cut flowers and foliage.