NZ kiwifruit packers find Psa symptoms in 'tolerant' varieties
Signs of secondary Psa-V symptoms have been seen in both Zespri's SunGold (G3) and Turners & Growers' Enza Gold (A19), which have been seen as possible alternatives to the highly susceptible Hort16A, or Zespri Gold.
Seeka chief executive Michael Franks tells www.freshfruitportal.com the plants are showing the earliest signs of 'waking up' with spring, and along with it the industry is still trying to gauge what these early Psa-V symptoms will mean.
"What we've seen in males throughout the Te Puke region is what we’d call secondary symptoms such as red exudates and white exudates, and in a sprinkling of the female plants in the Hayward green but not as widespead as in the males," he says.
"We’ve also seen it in some cases in the new Zespri G3 varieties, and what we’re uncertain about yet is whether either of those detections is significant but what we can say is that they are unwelcome, it can't be a good thing.
"We’d always anticipated we might see some infection in G3 but the fact that we are seeing some is unwelcome."
He says the symptoms last year in Hayward plants were mostly confined to leaf spotting and some exudates in male vines, but it was not as widespread.
"Last year we saw some exudates in green plants, in green males, but nothing like we have seen on the scale of the last week."
He adds the symptoms have got the industry 'spooked', as it is not yet known how significant they will be.
Aerocool general manager Richard Nicholson says Psa-V symptoms had been seen across the board with the varieties his company is involved in, although the degree varied.
"Certainly with the A19 we have seen Psa hit it and it has proved to be more tolerant than 16A, and then with the Enza Red I’ve got two orchards surviving very well and one orchard that’s decimated, so it’s a bit hit or miss.
"Certainly with the A19 gold it is following the same path as Hort16A, slowly but surely.
"One of my G3 orchards has had secondary symptoms and we’ve removed a few plants, with G9 I’ve had complete orchards removed, and with Haywards I’ve lost a whole pile of chieftan males as well."
Franks says there is no 'blanket statement' that could summarize returns at the moment for the industry, other than that while both gold and green volumes have been reduced, sales have been going well to date.
"Firstly, the gold crop, which last year was at 30 million trays this year is at something like 24 million, and that 24 million could be better than expected.
"However, some regions like Opotiki and Te Kaha had bumper yields, and regions like Te Puke were severely hit, and in our own case Seeka handled around half the volume of gold this year than last year, and the outlook going forward is that gold volume will significantly reduce.
"The green volume was also hit, but perhaps more by the containment protocols than by Psa itself.
Nicholson says Zespri's reports of higher prices per tray meant growers would likely be better off this year.
"But some of the issues around residue testing may negate some of that increase as well."