New Zealand has halted all apple exports to China for the rest of the season after rot was found in several batches at the Chinese border.
The Ministry for Primary Industries said three consignments - each containing about 1200 cartons of apples - had been quarantined by Chinese officials.
The 'post-harvest' rot was caused by the fungus Neofabraea alba and did not pose any food safety risk but officials had identified the fungus as a pest for plant health reasons, MPI said.
Stephen Butcher, MPI's manager of import and export plants, said a voluntary halt on all apple exports to China was now in place for the rest of the season.
"Industry has informed us that in response to the rot being detected - and considering this apple export season is almost over - it has voluntarily suspended all apple exports to China for the remainder of the season," he said.
Butcher said the New Zealand Government and apple industry were working with Chinese quarantine officials to provide technical and scientific information about the fungus.
MPI and Ministry of Foreign Affairs and Trade (MFAT) officials had met with counterparts in Beijing and were continuing discussions.
"These kinds of notifications happen from time to time in international trade," he said.
The apples originated from a small number of production sites and pack houses in Hawke's Bay.
Alan Pollard, chief executive of Pipfruit NZ, said Chinese officials detected the rot about two weeks ago.
He said the season had "practically finished" so the impact of halting exports would be minimal this year.
But it was "possible" this event could result in China being unwilling to accept New Zealand apples next year.
"It's a concern in the sense that China is an important trading partner for us," Pollard said.
He was confident New Zealand officials could reassure China and gets things back on track though.
"We've got a really good dialogue going with them. It's a normal part of trade so it's something we're used to and we're extremely good at managing."
To date this year, New Zealand has exported 320,000 tonnes of apples and 9,500 tonnes of that went to China.
"It's a small percentage but it's still an important growth market for us," Pollard said.
"What we're trying to work on is the management of fruit before it leaves New Zealand to minimise the risk of this happening."
An example of why rot might set it was if the cooling system in a shipping container failed, he said.
Chinese officials have asked that no apples from the Hawke's Bay sites involved be exported to their country.
Pollard said apples from those sites had been redirected to other markets.
The apple quarantine comes at a time when New Zealand's dairy industry is working hard to rebuild trust with Chinese consumers after last month's Fonterra botulism scare.
Local companies are losing up to $2 million in sales in China each week as a result of the dairy co-op's contamination fiasco, according to the New Zealand Infant Formula Exporters Association.