Honey producers concerned about myrtle rust impact on manuka

If you believe you have seen a myrtle rust infection, take a photo and contact MPI on 0800 80 99 66. Avoid touching the plant. Photo supplied

Bay of Plenty honey producers are taking a wait-and-see approach to news that fungal disease myrtle rust had been found in Northland.

The Ministry for Primary Industries said on Friday that the disease had been found at a plant nursery in Kerikeri - the first discovery of its kind on the New Zealand mainland.

Yesterday the ministry said rust-like symptoms had been observed at a second Kerikeri plant nursery. Initial test results were negative for the disease but could be a false negative result.

A third property is also being tested.

"We're dealing with a very fluid situation here," ministry director response Geoff Gwyn said.

"Given the ease with which this fungus can be spread by the wind, on contaminated footwear and clothing and on tools, our staff are following stringent protocols to avoid spreading the disease."

The disease has the potential to seriously affect manuka, pohutukawa, rata, feijoa and guava plant species, among others, the ministry said.

Scott Coulter, chief executive of Te Puke-based manuka honey producer Comvita, said last week it was too soon to speculate on the potential impact on the industry.

"We understand when myrtle rust arrived in Australia in 2010 there were concerns about the impact it might have on honey production. However, to date there seems to have been no effect."

Stock in the publicly listed company fell 9.4 per cent on Friday.

Neil Mossop, the owner of Tauriko's Mossop's Honey, said there were "a lot of unknown factors" at this stage.

Nobody knew how myrtle rust would behave in the New Zealand climate and soils, or whether it would impact nectar production or new plant growth, he said.

Mr Gwyn said the disease, present in many locations around the world, was known to have different effects on plants from country to country and location to location.

A team of 70 from the ministry, Department of Conservation, AsureQuality and the Northland Regional Council were in Kerikeri over the weekend.

They are inspecting the area around the initial infection, tracing customers of the nursery, and encouraging people to be on the lookout for the disease.