A kiwifruit orchard is under quarantine after the discovery of a disease which may be the same as that which has caused substantial damage to green and gold fruit in Italy.

Peter Ombler, president of New Zealand Kiwifruit Growers, would not confirm the location of the North Island orchard but said reports that a strain of the bacterial kiwifruit vine disease, Pseudomonas syringae pv actinidiae (Psa), may be present on the orchard were first made on Friday.

"Tests are under way to find out exactly what the disease is and at this stage we don't know what we are dealing with. It could be virulent, it could be harmless," he said.

The disease does not pose a food safety risk for those eating kiwifruit. Kiwifruit vines are coming into flower now and have yet to set fruit which won't begin to be harvested until March or April next year.

Kiwifruit exports are worth more than $1.5 billion to New Zealand.

In the year to November 2009, kiwifruit exports amounted to 64.4 per cent of fruit and nut exports, and 45.7 per cent of all horticultural exports from New Zealand.

Biosecurity Minister David Carter has just issued a statement reassuring kiwifruit growers that the Government was "treating the discovered vine infection on a North Island kiwifruit orchard very seriously, and is making all necessary resources available."

"Swift action is underway to confirm whether the vine infection is Psa, a bacterial kiwifruit vine disease. MAF Biosecurity New Zealand is working closely with ZESPRI, Plant & Food Research and New Zealand Kiwifruit Growers Inc," said Carter.

"We are confident that robust testing will quickly determine the next steps.

"This potential risk to our kiwifruit industry is being taken seriously. While the strain of the disease is not yet known, all necessary precautions have been put in place on the orchard to avoid the disease spreading.

"It is imperative that a considered and responsible approach to this potential threat is taken by all primary sector stakeholders while the kiwifruit industry and Government works out exactly what we are dealing with," said Carter.

It is not yet known what effect Psa would have on the kiwifruit industry here if it is confirmed.

It is understood the disease acts differently in different parts of the world - Japan still produces kiwifruit despite the disease having been detected.

While he was not aware of the Psa scare, Andrew Coker chief executive of Priority One - the Western Bay of Plenty's economic development agency - said anything that threatened the kiwifruit industry was of extreme concern.

The kiwifruit industry represented 20 per cent of the Western Bay of Plenty's GDP, he said.

"It's a very significant industry and a large employer, increasingly so throughout the year with seasonal changes with different varieties.

"It's a leading export industry and is in substantial growth mode."

The industry had doubled in size in the last 10 years, and at the Zespri AGM in August a commitment was made to triple exports by 2021, he said.

"There's not many industries in New Zealand with that scale of growth."

Concerns raised by the orchardist and a consultant were first reported to Plant&Food, Ombler said. MAF Biosecurity New Zealand and kiwifruit exporter Zespri were informed and a series of meetings with industry players were held throughout the weekend.

"It is appropriate that we act with caution until we know exactly what we are dealing with. The strength of the kiwifruit industry is that it is integrated and it is possible to involve key players at very short notice," Ombler said.

MAF Biosecurity New Zealand said it should be known by Wednesday if the vine infection was Psa.

Precautions had been taken to mitigate any risk of spread, including issuing a Restricted Place Notice on the orchard, MAF Biosecurity said a statement. If Psa is confirmed, MAFBNZ would work with Zespri and NZKGI to implement an agreed action plan.

Meantime, Zespri is keeping industry leaders up to date with the current situation, while seeking to understand how widespread the issue may be and to encourage best-practice orchard hygiene.

Ombler said bacterial diseases in kiwifruit were not uncommon and most could be controlled by normal orchard management techniques. Even if the disease was identified as Psa, it may not present the same problems for New Zealand growers as it had for those in Italy where growing conditions were different, he said.

HortNZ president Andrew Fenton said there was an "embargo" on information and he did not wish to comment until later today.

See the Maf news release here.

* Pseudomonas syringae pv actinidiae (Psa or batteriosi) is a disease that affects kiwifruit (actinidia)

* Psa has never been confirmed as being present in New Zealand.

* First identified on green kiwifruit vines (Hayward) in Japan about 25 years ago.

* Psa was first identified on green kiwifruit vines in Italy in 1992 and has caused substantial damage to both green and yellow-fleshed kiwifruit in recent years.

* Psa is also present in Japan and Korea where the disease is controlled by implementing appropriate agriculture practices