The fungal plant disease has already been confirmed at properties in Northland and Taranaki.
A positive detection of myrtle rust has been made in the Waikato region.
The latest finding, in Te Kuiti, was identified in a small number of plants at a nursery, as a result of MPI tracing sales of plants from another positive nursery.
MPI has personnel on the ground in Te Kuiti and restrictions are in place on the movement of risk goods from the property. The property will be treated with fungicide.
The disease causing fungus has been found at a mix of properties including nurseries, plant retailers and distributors, an orchard and private gardens.
People can report any suspected signs of myrtle rust to MPI's Exotic Pest and Disease Hotline on 0800 80 99 66. Do not touch the rust or the plant. Note the location and take photos of the symptoms and the plant.
