January 2019 Myrtle Rust update

January 30, 2019

In this update you will find:

  • Where has myrtle rust been found
  • Take our online training programme to help identify myrtle rust
  • Increase in myrtle rust finds during the summer and what to check for
  • New evidence that myrtle rust can reproduce sexually

You can download the PDF of the newsletter here

Where myrtle rust has been found

895 infected properties have been reported since May 2017.

National detections of myrtle rust to date:

Northland - There are 36 sites/properties in Northland with confirmed infection. Most of these are in Kerikeri.

Taranaki - There are 283 sites/properties in Taranaki with confirmed infection. Most of these are in New Plymouth and Waitara.

Waikato - There are 106 sites/properties in the Waikato region with confirmed infection. Most of these are in Otorohanga and the Taupo district.

Bay Of Plenty - There are 174 sites/properties in the Bay of Plenty with confirmed infection. Most of these are in Te Puke and Bethlehem.

Auckland - There are 179 sites/properties in the Auckland region with confirmed infection. Most of these are in Remuera.

Wellington - There are 55 sites/properties in the Wellington region with confirmed infection. Most of these are in Lower Hutt and Upper Hutt

Manawatu-Whanganui - There are 25 sites/properties in the Manawatu region with confirmed infection. Most of these are in Fielding.

Tasman - There are 21 sites/properties in the Tasman region with confirmed infection. Most of these are in Collingwood, Patons Rock and Pohara.

Gisborne - There are 3 sites/properties in the Gisborne district with confirmed infection. These sites are all at the Northern tip of the East Cape.

Marlborough - There are 8 sites/properties in the Marlborough district with confirmed infection.

Nelson - There are 5 sites/properties in Nelson with confirmed infection.


Take our online training programme to help identify myrtle rust

Biosecurity New Zealand, in collaboration with the Department of Conservation has developed online training courses about myrtle rust. The courses are available to everyone but are particularly suited to those running community education events.

The online course covers:

  • Background on myrtle rust in New Zealand
  • Examples of myrtle rust and the myrtle family
  • What to do if you find myrtle rust and how to dispose of infected plant material
  • Myrtle rust research programme
  • Myrtle rust seasonal variations
  • Spread of myrtle rust
  • Identifying the scale of impact of myrtle rust

The two modules take around 35 minutes each to complete.

Register to get access to the course.


Increase in myrtle rust finds during the summer and what to check for

There has been an increased level of positive myrtle rust detections during the summer months so far. The summer months provide ideal conditions for the spread of myrtle rust as infection risk is directly related to the duration of high relative humidity and temperature.

The Department of Conservation is extremely interested in any suspected myrtle rust on Public Conservation Land. So if you are spending time in our national parks and reserves over the summer please keep a special eye out for myrtle rust.

Basically the warmer and more humid it is, the better – like all fungi really. Therefore, late summer and autumn are likely to be the worst time for infection and spore risk.

If you think you see symptoms remember to not touch or collect samples, but take pictures and report it to Biosecurity New Zealand’s Exotic Pest and Disease Hotline on: 0800 80 99 66.

All plants in the myrtaceae family are susceptible to myrtle rust. For a list of myrtle plants in New Zealand you can visit the New Zealand Plant Conservation Network. 


Sexual reproduction of Austropuccinia psidii in New Zealand

Myrtle rust is known to produce the teliospore stage in New Zealand. This spore stage is different from the asexual urendiniospore stage and indicates that the fungus is capable of reproducing sexually. Sexual reproduction introduces genetic variability, increasing the risk to New Zealand, as it allows fungi to adapt to new environments and possibly affect new hosts.

It is not yet known how this disease will affect New Zealand species, but myrtle rust will likely continue to affect a wide range of susceptible myrtle plants. Overseas its impacts have varied widely from country to country and plant species to species.