Psa-V spread continues in Waikato

19:12, Nov 16 2012

Nearly 30 kiwifruit orchards in the greater Waikato region are now infected with Psa-V, the vine-killing disease that has brought the gold fruit export industry to its knees.

An additional 36 orchards in the Waihi area have the bacterial infection.

There are 131 registered kiwifruit orchards in Waikato, which until Psa-V hit in August, contributed around 20 per cent of the country's export organic kiwifruit crop. Last year they earned $29 million and provided jobs for 300 at the season's peak.

The Kiwifruit Vine Health agency said that as of this week 14 Waikato orchards had been confirmed with the disease and 15 on the Coromandel Peninsula.

The next kiwifruit harvest is in April and KVH Waikato co-ordinator Richard Glenn said for many growers this would be their last gold fruit crop until new graftings of varieties which hopefully were less vulnerable became established.

"It's going to be a tough five years. Kiwifruit growing in New Zealand has changed forever."


KVH said 74 new Psa-V cases were notified this week. They included one in Waihi, three in the Waikato and four in Coromandel.

The disease, which was discovered in kiwifruit growing capital Te Puke two years ago, has now spread throughout the North Island, with 1887 orchards, or 65 per cent of all kiwifruit growing hectares, now infected, although some orchards are only partially infected.

The disease, believed to have originated in China, has proved particularly lethal to gold kiwifruit vines and in particular the Zespri variety Hort16A, although green fruit vines are also affected.

Gold fruit exports were a lucrative earner for the former $1 billion blue chip export industry.

KVH says Psa-V cannot be eradicated now it is established and Glenn said the message was being "hammered" that regular defensive copper spraying was now essential. Growers were learning a lot about how not to accelerate the disease, through new pruning and management methods and strict orchard hygiene measures, he said.

A Lincoln University study earlier this year concluded Psa-V would cost the industry $900 million.