MYRTLE RUST found in Kerikeri & Taranaki

22 May 2017

If you think you have seen this fungus call MPI’s exotic pests and diseases hotline on 0800 80 99 66.
Take a photo - do not attempt to touch or collect samples as this may increase the spread of this disease.

Myrtle rust has now been found in both Kerikeri and Taranaki. The Ministry for Primary Industries (MPI) and Department of Conservation (DOC) have already put precautions in place to help stop any further spread. They are working with iwi, industry and local authorities to learn more about how this detection can be managed.

Myrtle rust is a serious fungal disease, readily spread by wind, that attacks plants of the Myrtaceae family. It can also be transported on clothing and equipment. If you think you’ve come into contact with myrtle rust spores in New Zealand or overseas, please wash your clothes and clean your equipment (such as boots and tools) thoroughly.

Host plants

Many New Zealand natives are members of the Myrtaceae family, including Pohutukawa and Rata (Metrosideros), Kanuka (Kunzea), Manuka (Leoptospermum), Ramarama (Lophomyrtus), Rohutu (Neomyrtus), Swamp maire (Syzygium).  There are 29 species in these genera.

Many exotic species grown in New Zealand are also members of the Myrtaceae family. Eighty percent of Australia’s native flora are members of the Myrtaceae family, notably species in the genera Agonis, Angophora, Callistemon, Chamelaucium, Corymbia, Eucalyptus, Eugenia, Kunzea, Lophomyrtus, Leoptospermum, Metrosideros, Myrciaria, Myrtus, Pimenta, Psidium, Syncarpia and Syzygium.   All these feature in New Zealand landscapes. 

The popular feijoa (Acca sellowiana) is also a member of the Myrtaceae family.

All members of the Myrtaceae family must be considered potential hosts of myrtle rust because the fungus has demonstrated in both Australia and Hawaii that it finds new myrtaceous host species which were not known hosts previously.

How you can help

Myrtle rust spores are highly mobile. Like many rusts, they are easily spread across large distances by wind. They can also be transported by infected plant material, on clothing, equipment and vehicles, by insects and in rain splashes. Early detection gives us the best chance of containing an incursion.

We are all part of a team of 4.7 million New Zealanders on the lookout for serious pests and diseases and gardeners are urged to immediately inspect all their gardens and nearby vegetation, especially varieties in the Myrtaceae family.

If you find anything suspicious, call MPI’s exotic pests and diseases hotline on 0800 80 99 66.

What to look out for

Myrtle rust attacks young, soft, actively growing leaves, shoots and young stems, and sometimes flowers and fruit. Initial symptoms are powdery, bright yellow or orange-yellow pustules on leaves, tips and stems. The developing lesions may cause a deformation of the leaves and shoots, and twig dieback and plant death if the infection is severe and the species highly susceptible.
Look for:

  • bright yellow powdery eruptions appearing on the underside of the leaf (young infection)
  • bright yellow powdery eruptions on both sides of the leaf (mature infection)
  • brown/grey rust pustules (older spores) can appear on older lesions
  • leaves may become buckled or twisted and die off

Rusts of this type are rare on many native species - any sighting should raise suspicion.

What to do if you find it

If you think you've seen the symptoms of myrtle rust, do not touch it.

  • Call the MPI Exotic Pest and Disease Hotline immediately on 0800 80 99 66.
  • If you have a camera or phone camera, take clear photos, including the whole plant, the whole affected leaf, and a close-up of the spores/affected area of the plant. 
  • Don't touch it or try to collect samples as this may increase the spread of the disease.

To prevent rust of any type in your garden, apply preventative copper-based fungicides; but should you suspect you have found Myrtle Rust, do contact MPI FIRST.

More information is available at:

 



5-May-2017

 

myrtle rust

myrtle rust lophomyrtus
Myrtle Rust on Lophomyrtus (ramarama)

rata
Climbing rata Metrosideros fulgens