Saturday, 06 February 2016 11:55

Kiwifruit killer shows resurgence

Written by  Pam Tipa
KVH’s Barry O’Neil says more Psa has been seen this season than for years. KVH’s Barry O’Neil says more Psa has been seen this season than for years.

The kiwifruit industry has seen a resurgence of vine-killing disease Psa-V this year, but still expects a bumper crop.

"We have definitely seen more Psa this spring and longer into summer than what we've seen for the last couple of years," says Kiwifruit Vine Health chief executive Barry O'Neil.

"We put that down to a number of factors: a colder wetter winter-spring, windier conditions in spring as well and some growers becoming a little too complacent with their management approaches, believing Psa is no longer a worry for them.

"It is a reminder for all growers that Psa is still here and will definitely rear its ugly head when conditions are favourable – if the growers are not very pro-active."

O'Neil says Psa is still very widespread.

"Parts of lower Waikato have had some very bad problems, especially some of the organic growers in the region.

"Obviously it is more challenging for organic growers. They don't have the tools conventional growers have. There are significant restrictions on what they can put onto their crops.

"But we've seen Psa this year from Kerikeri to Whanganui, Coromandel and Gisborne. Even in the main Bay of Plenty kiwifruit growing area Te Puke they are still seeing in some situations quite widespread Psa."

Normally it is on the more challenged sites, he says.

"The lower lying colder sites are where we are seeing more, but not always. It is certainly more of an issue this year than we have seen for a little while," O'Neil adds.

"To counter that, on the other side of the equation we have had good flowering, pollination and fruit set. So even though there has been more Psa we are still looking at a significantly larger crop.

"Gold will be significantly up on last year as more G3 comes into production and the Green crop may not be dissimilar to the record crop we had last year. So even though Psa has been bad, certainly production continues."

Kiwifruit Vine Health wants growers to ensure they have an effective crop protection programme – their sprays regime – to minimise the impact of Psa. On-orchard hygiene – the cleaning of tools between vines or between days – hasn't been maintained as well as it should, says O'Neil.

Thirdly, growers must cut out infection when they see it so it doesn't spread.

"Those are the three areas I suggest would be the most important in which growers must remain proactive and vigilant.

"Normally at this time of year it's hot and dry and we don't see any Psa at all. We are still seeing it – not as bad as what it was earlier, but it is still there.

"In some orchards on more challenged sites they may have to cut out up to 20% of their canopy because of Psa. Some regions have more susceptible varieties."

The older, more susceptible cultivar Hort16a hasn't gone from all regions of New Zealand. It is still present in the Far North and on the East Coast and those growers are finding it as hard as Bay of Plenty growers found years ago, he says.

"It causes the infection to get established through the vine into the root stock," O'Neil adds. "The sooner it is removed from a region or an orchard that has Psa the better."

More like this

Kiwifruit sector's big night out

The turmoil and challenges faced by the kiwifruit industry in the past 30 years were put to one side but not forgotten at a glitzy night for 400 kiwifruit growers and guests in Mt Maunganui recently.

Kiwifruit sector celebrates three milestones

Over 400 of New Zealand’s stalwart kiwifruit growers gathered in Mount Maunganui this week for a celebration to recognise three major milestones in the industry’s history.

Featured

Massey Research Field Day attracts huge interest

More than 200 people turned out on Thursday, November 21 to see what progress has been made on one of NZ's biggest and most comprehensive agriculture research programmes on regenerative agriculture.

Expo set to wow again

Stellar speakers, top-notch trade sites, innovation, technology and connections are all on offer at the 2025 East Coast Farming Expo being once again hosted in Wairoa in February.

A year of global challenges

As a guest of the Italian Trade Association, Rural News Group Machinery Editor Mark Daniel took the opportunity to make an early November dash to Bologna to the 46th EIMA exhibition.

National

Winter grazing warning

Every time people from overseas see photographs of cows up to their hocks in mud it's bad for New Zealand.

ANZ defends farm lending rates

The country's largest lender to the agriculture sector says it's not favouring home loans over farm and business lending.

Machinery & Products

Expo set to wow again

Stellar speakers, top-notch trade sites, innovation, technology and connections are all on offer at the 2025 East Coast Farming Expo…

A year of global challenges

As a guest of the Italian Trade Association, Rural News Group Machinery Editor Mark Daniel took the opportunity to make…

» Latest Print Issues Online

The Hound

Review SOEs!

OPINION: NIWA has long weathered complaints about alleged stifling of competition in forecasting, and more recently, claims of lack of…

Bank reset

OPINION: Adding to calls to get banks to 'back off', NZ Agri Brokers director Andrew Laming has revealed that the…

» Connect with Rural News

» eNewsletter

Subscribe to our weekly newsletter