A University of Otago biochemist is almost certain the kiwifruit vine disease PSA entered New Zealand on unpurified pollen from China, after biosecurity rules were inexplicably relaxed.
An independent review released on Wednesday did not determine how PSA arrived in New Zealand, but found there were shortcomings with biosecurity systems.
These included inadequate import controls on kiwifruit pollen and insufficient nursery stock import regulations.
Biochemist Russell Poulter has examined PSA strains and told Nine to Noon on Friday the New Zealand variety almost perfectly matches one originating from the Chinese province of Shaanxi and processed in Te Puke.
Dr Poulter says the 2009 shipment would give the PSA bacterium the right amount of time to produce the symptoms first discovered in Te Puke in 2010 and importer Kiwi Pollen was following the rules set down by the then Ministry of Agriculture and Forestry at the time.
Dr Poulter says all signs now point to the 2009 shipment of unpurified pollen or anthers, the pollen-bearing part of unopened flowers, imported for use on kiwifruit orchards.
Dr Poulter says the usual condition was that it had to be milled, meaning it comes across the border as purified pollen, but for a reason that was not clear that condition was relaxed to state the pollen 'may be milled.'
"If you say it 'may be milled' before import you're clearly signalling that, on the other hand, you're willing to contemplate it being milled after import.
"And that's tantamount to a permission to import unmilled pollen which is really a surprising thing to do in the face of an outbreak of PSA which was devastating Italy."
Ministry for Primary Industries director general Wayne McNee says the import standard changed because scientific information in 2007 suggested PSA could not be transmitted via pollen.
He says the then Ministry of Agriculture and Forestry was not fast enough to change its rules when that was shown to be wrong
"Clearly when the risk changed we should have gone back and looked at the rules we had in place, we should have communicated with the industry. We didn't do so and that has been highlighted in the report."
Mr McNee says all of the recommendations in the report are being implemented.
Union calls for more resources
The Public Service Association says the independent review of the biosecurity response to the kiwifruit disease outbreak reinforces the concern it has had about biosecurity cutbacks.
The union's national secretary, Richard Wagstaff, says the report is a wake-up call on the need to boost biosecurity.
He says the association takes issue with the recommendation that the ministry should look at focus more on managing the risks for economically significant industries by moving resources from smaller, less strategic sectors.
Mr Wagstaff says resourcing should be increased rather than taken from areas seen as less economically significant.
Meanwhile, a Bay of Plenty kiwifruit grower is calling for a Commission of Inquiry into how the disease entered New Zealand.
Rob Thode from Papamoa says that would help to ensure other primary sectors don't suffer the same fate as the kiwifruit industry.