New Zealand has temporarily suspended the importation of Australian cucurbits, except those grown in Queensland, after a plant virus was found on a consignment of Australian watermelons.

New Zealand authorities confirmed the detection of Cucumber Green Mottle Mosaic Virus (CGMMV) on a batch of watermelons from the Northern Territory two weeks ago, and suspended cucurbit imports on August 20.

This week, New Zealand amended its import requirements for Australian curcubits to allow fruit sourced from CGMMV-free areas in Queensland to enter the country.

CGMMV is a soil-borne plant virus which affects cucurbit crops such as watermelons, pumpkins, zucchinis and cucumbers, but is not harmful to humans.

The plant virus was first detected the Northern Territory's Katherine region in 2014, where it almost wiped out the $60 million watermelon industry, and has since been found on farms in Queensland and Western Australia.

Dianne Fullelove from the Australian Melon Association said the infected fruit found in New Zealand came from a Northern Territory farm found to have CGMMV in 2014.

"This virus is extremely difficult to eradicate from soil once it is present on a farm, so it is unfortunate for that farm that they are still getting outbreaks of the virus," Ms Fullelove said.

Australian melon exports to New Zealand were worth $9 million in 2017, and melons were Australia's 5th largest fruit export across all markets.

Some Queensland curcubits allowed into NZ

The Department of Agriculture and the melon industry have been working to certify Queensland melon growers for export, where the bulk of curcubit exports are currently being produced.

Ms Fullelove said the New Zealand Ministry for Primary Industries has agreed to accept Australian biosecurity clearances.

"All cucurbit growers will be asked to register with the Commonwealth biosecurity and export agencies, and their farm will be certified as being free from CGMMV because of the general surveillance and movement controls that have happened in Queensland," she said.

"New South Wales and Victoria are also getting data together for the surveillance that they have done in the past few years so that the growers in the other states will be certified as well, when they come into production."

Fruit that has not ripened correctly, because of the Cucumber Green Mottle Mosaic Virus. ( Supplied: Barry Conde/DPIF )

However Australian and New Zealand authorities disagree on the method of transmission for CGMMV.

Australian biosecurity controls only regard plant matter and soil as viable methods to spread the virus, whereas New Zealand authorities include fruit.

As a result, Australian fruit was not checked for CGMMV before it was exported to New Zealand.

The Department of Agriculture has now agreed to certify that all Australian curcubits exported to New Zealand has been produced on a farm certified as CGMMV-free.

Ms Fullelove said the industry was working to reopen the cucurbit trade with New Zealand as soon as possible.

"[New Zealand] is our third, almost second, largest market for melons, so we are very keen to maintain the trade with New Zealand," she said.

"We are very pleased that they have engaged so well with the Commonwealth departments to discuss this and find a resolution; it has been extremely quick - it probably doesn't seem like that to the growers who have not been able to send their fruit for the last couple of weeks - but in fact in the order of things, this is looking like a quick resolution of this issue."

In a statement to ABC Rural the NT Department of Primary Industry said: "the Australian Government is working with State and Territory governments to develop a workable solution that will allow Australian cucurbits to be exported to New Zealand while minimising disruption to local growers.

"The Northern Territory Government has contacted local commercial cucurbit growers and explained the current situation and the new measures for cucurbits that have been requested by the New Zealand Government," the statement said.

"The majority of the Northern Territory's cucurbit growers sell domestically, and are not affected by the changes being requested by New Zealand.

"With the cucurbit season almost complete in the Northern Territory, the Northern Territory Government will work with industry and the Australian Government to prepare and facilitate market access for next season."