Scientists launch $1.4m myrtle rust study

Myrtle rust, pictured on willow myrtle. Photo / File

Scientists will team up in a new $1.4 million project to help combat deadly fungal disease myrtle rust.

It comes as the incursion has already spread to nearly 50 sites in Northland, Waikato, Taranaki and Bay of Plenty, posing a major threat to cherished native myrtle species like pohutukawa, manuka, rata, feijoa and bottle brush.

Officials have warned it will likely be impossible to contain the spread of the scourge, which infected as much of a third of pohutukawa on Raoul Island before first being found at a Kerikeri nursery last month.

A new collaboration between researchers at Plant and Food Research and Scion will attempt to establish the susceptibility of key species to myrtle rust, build scientific knowledge for successfully storing germplasm of myrtle species, and develop "in the field" plant pathogen detection and surveillance systems.

"This is very important and timely research now that myrtle rust is present on the New Zealand mainland," said Plant and Food Research scientist Dr Grant Smith, who will lead the three-year project.

The work is being supported by the Government's Catalyst Fund and will see the scientists working with experts from Plant Health Australia, Better Border Biosecurity, Queensland Department of Agriculture and Fisheries, NSW Department of Primary Industries and the Wellington Botanic Gardens.

"New Zealand and Australia have much to learn from each other with regards to the invasive species in their respective countries," Plant Health Australia executive director Greg Fraser said.

"Myrtle rust is something that Australia has been dealing with for seven years and our experience can really help New Zealand."

The Herald is aware of frustration among some scientists that authorities weren't better prepared for myrtle rust - and why a specific strategy wasn't put in place before it arrived.

As early as 2011, an assessment produced for the Government warned of a potential "landscape scale" impact on New Zealand.

Its eventual detection triggered an eleventh-hour seed-banking effort around the country, with the Department of Conservation directing hundreds of officials to collect seeds of more than 30 native plant species.

The Ministry for Primary Industries (MPI) has however told the Herald it was "very well prepared" for the situation, having put in place surveillance measures, importing restrictions, sector collaborations and modelling work ahead of the incursion.

Meanwhile, the Tree Council has today called for a temporary ban on all plant movement across New Zealand to prevent further spread.

"While myrtle rust may spread slowly via wind dispersal of spores there will be far more rapid spread via plant movement, especially infected plants, and on people's equipment, clothes and skin," said the organisation's chair, Sean Freeman.

"During the current planting season the risk is extremely high that unidentified infections will be spread this way and the resulting multiplying spread and outbreaks will be extremely difficult to deal with."

The council urged MPI to use its powers under the Biosecurity Act to put a ban in place.

"We must act immediately or widespread infection will be too difficult to treat and the whole of New Zealand risks being infected."

• Anyone believing they have seen myrtle rust on plants in New Zealand were asked to call MPI on 0800 80 99 66. It was important for people not to touch the plants or attempt to collect samples as this would spread the disease.