Seeka, New Zealand's largest kiwifruit grower, is worried that symptoms of the PSA vine disease are appearing in blocks of the new G3 variety of gold kiwifruit.
Zespri is relying on G3, which has shown a tolerance to PSA, to be the cornerstone variety of gold kiwifruit in the future.
Seeka chief executive Michael Franks says the fact that symptoms are showing up so soon after the vines have come out of their dormant winter state is a major concern.
He says secondary symptoms in the green male vines have been detected throughout the catchment and a few female vines show the same symptoms.
Mr Franks says the symptoms have been seen in all of the varieties, and though it's only a very small number and it's still very early in the growing season, there is caution about what will happen next.
He says the next two or three months will be critical.