Psa: Disease casts sobering shadow

It has been two years since Psa, the bacterial kiwifruit vine disease, was discovered in Te Puke. It has now been identified in 1995 of New Zealand's orchards and the industry has resigned itself to the fact it will have to live with the devastating disease. Julia Proverbs talks to growers and industry leaders about the way forward

John Cook's kiwifruit orchard is abuzz with bees.

As they hover hungrily over blossom-laden vines, collecting little beads of pollen on their tiny legs, he smiles.

It is a good sign.

"If the bees are not working, there's something wrong with the vines," says John, who has been a kiwifruit orchardist for 25 years.

Standing in his Te Puke orchard, under a lush, green canopy, he is optimistic about this year's crop.

Flourishing, it has the sweet earthy smell of spring, but take a closer look and you can see where Psa, the kiwifruit vine disease, has left its mark.

Black spotting scars some of the leaves of the male plants - a sobering reminder that this is an industry that continues to live under the disease's shadow.

The 35-year-old vines, which produce the green Hayward kiwifruit, have undergone a rigorous spraying programme and a constant vigil is kept for signs of the aggressive bacterial disease.

Frequent copper sprays waterproof the leaves to prevent the bacteria from penetrating the plants, while blackened shoots are immediately cut off and disposed of.

"Our spraying programme is five times the normal processes carried out in the past," says John, who estimates his costs have increased by 20 per cent.

"It's a bit of a struggle but our green orchards which looked dicey back in October have recovered well and are looking promising for this current harvest. They showed signs and there have been some stories of some not very pretty outcomes but at this stage our vines look to be doing all right," he says.

"We've come to realise this is the landscape of the future of growing kiwifruit in Te Puke."

The green, more resistant variety, makes up the bulk of his orchards, which total 20 hectares.

However, two years ago at the onset of Psa, he lost his entire gold crop.

The four-hectare orchard of susceptible Hort 16A was one of the first to fall victim to the disease.

"The cane started dying back. We didn't see spotting. In the green, you see spotting then die-back. In gold you don't see spotting," explains John.

He has since replanted with the more tolerant Gold3 variety, but it will be two to three years before he sees any returns.

"The longer-term view is that some of the new varieties are showing greater profitability and greater promise but we've got to keep business alive in the meantime. We've got to maintain some cash flow and maximise greens in the meantime."

Orchardists, many of whom are approaching retirement age, are doing their best under trying conditions, says John.

"Growers are working harder. There are more tasks to do on orchards and they are either engaging other people to do it or doing it on their own. Most of us are at retirement age. We were thinking we would be able to slow down but it's just not happening."

He is guarded about the emotional toll it has taken on him personally, preferring to focus on the positive.

"I'm trying to be proactive, rather than reactive. It becomes a mindset. People are affected differently to each other. We are seeing the range of human emotions - supreme optimism and supreme pessimism and everything in between. I like to consider myself at the top end."
 

New Zealand Kiwifruit Growers president Neil Trebilco says the kiwifruit industry is on a "steep learning curve".

"There is still a lot we have to learn ... we're still learning optimal timing of things, of when, how much and how often," says Neil. "Inevitably growers are going to get better with time."

The industry knew at the outset that there was no turning back from Psa, but had hoped to contain the spread, he says.

"What we didn't know was how fast it would spread to other areas. There had been a limited spread to Katikati and Tauranga. This year it has advanced significantly into regions that didn't have it before. We hoped it would stay out of those areas for years," says Neil.

"It's through all the growing areas in New Zealand now. The thinking is that even if orchards are not showing symptoms it's likely to be in the orchard already."

Psa is spread primarily by plant material and equipment, and the weather.

Some growers are spraying their crops as many as three times a week during high-risk periods, says Neil.

"There is a huge cost in this for growers. Undoubtedly Psa will affect profitability going forward. One of the things we know from other fruit crops is that they have had bacterial diseases for many years, but it's new for kiwifruit growers. We just have to learn to deal with it and make it work economically."

Despite the average age of growers being 58, most are still orcharding and doing what they need to do to go forward, says Neil.

"For the majority of people, it's extremely unfortunate because their kiwifruit orchards are the culmination of their life's work and earnings. It was part of their retirement plan. Right now if they sell up they will lose a lot of what they invested in."

He estimates Psa will rob the industry up to $100 million this selling season and possibly double that next year.

"Only time will tell. It really depends on the ongoing impact on the new G3 variety."

At its peak there were around 31 million trays of Hort16A produced. This year just one million trays of G3 were produced, expected to increase to two to three million next year, says Neil.

"A significant amount of wealth has gone out of the Bay of Plenty economy because of Psa," he says.

"Because people aren't hearing about it doesn't mean the impact is any less. If anything the impact is getting worse all the time. Having said that, we are are learning. We are getting reports some people appear to be controlling it."

Simon Limmer, Zespri's general manager of grower and government relations, says the kiwifruit industry is learning to live with Psa through new technology, new management practices and new varieties.

Two-thirds of the vulnerable Hort16A gold kiwifruit have been removed, including 100 hectares in Te Puke, with a view to replacing the vines with the G3 variety.

"G3 is not totally resistant, but it's more tolerant. You've still got to be doing an extremely good job to get G3 to come through as well," says Simon. "Growers are taking a far more cautious approach ... we are learning to live with it. We are seeing a range of results out there."
 

Spring is a time of "high anxiety" for growers, when the symptoms of Psa start to show after the winter, adds Simon.

"We know it's present in Hayward and Gold. Now we need to see what the impact looks like."

A range of factors affect a grower's ability to produce fruit, including how exposed an orchard is to wind and rain, how often it is sprayed and pruning techniques.

"Not everyone has been successful," he says.

"Growers always had a crop protection programme and it is evolving over time. Other crops do face these dilemmas. It's our turn. Growers have to reset their expectations as to what viability looks like."

More labour-intensive growing could see a shift to smaller orchards.

With Zespri's brand built around New Zealand's clean growing practices, the increased use of sprays is an issue that must be handled carefully by the world's largest kiwifruit marketer.

"We do have to strike a balance between protecting against Psa and not impacting on our brand," says Simon.

"There has been a huge amount of effort ... residue testing processes, consulting with growers, advising what products they can and can't be using. On the whole, the industry has responded well. We did 100 per cent testing last year and we will do it again this year to protect the brand."

In the background, the search continues for new varieties. Thanks to a 10-year breeding programme, Zespri has "a full pipeline of potential varieties".

New products are expected over the next five to 10 years, a pre-requisite now being a resistance to Psa.

"Nothing exists round the world that is resistant to Psa. In the meantime, a high degree of tolerance is as good as we can expect."

Ironically, while volumes of gold kiwifruit have been significantly reduced, the market remains strong.

The challenge for Zespri will be serving and maintaining those markets.

"We're going to have to be strategic. There is a recovery expected two to three years down the track. We will see volumes come back and those markets are important."

Until then, for many growers, it will be a case of trying to make ends meet.

"I think the toughest thing with our industry is we're a relatively small community - 80 per cent of growers are from the Bay of Plenty region. We know each other pretty well. There is a lot of pain for individuals out there. It's impossible not to be affected by that. The financial reality for some of these people is greater than we can estimate. It's pretty high," says Simon.

"But overall the industry is optimistic it's going to recover. The fact the market opportunity is really strong is a strong driver to find a way forward. Gold taught us the opportunity in new varieties."