Italy ruled out, China and Chile still contenders
NZ: Scientists track PSA source
Associate Professor Russell Poulter, Professor Iain Lamont and Dr Margi Butler, all from the University of Otago's Department of Biochemistry, have been working with the industry since November 2010 when the first outbreak was detected in Te Puke.
Since then they have been trying to uncover where the disease came from. There were three potential sources - Chile, China or Italy.
Initially the technology required to carry out genetic code sequencing of the disease was not available in New Zealand. However, last year saw the arrival of new advanced genomic technology into the country, which could now make discovering the source a possibility.
The results have shown that the New Zealand strain is different from that found in Italy, which rules out a European destination. Tis also proves once and for all that New Zealand was not the source for Italian outbreaks as some have claimed.
Through a process of elimination Chinese pollen now appears to be the most likely source of the disease in New Zealand.
What's more it appears that the Italian outbreak may also stem from China.
However, Chile still has to be conclusively rule out, but the results of this should not take long now.
"Having provided the tools, through sequencing, to recognise the different strains, we now want to determine the pathway by which the Psa came into the New Zealand. It's unlikely to be on someone's boots or via quarantined channels. And we know the particular strain did not originate from Europe. We need to know the pathway, so we can help other countries - and ourselves - avoid similar mistakes in future."
Dr Poulter says the kiwifruit Psa scenario has highlighted to him how critical it is to have such technology within New Zealand.
"New Zealand is a major agricultural and horticultural producer. It's what we are. It's how we earn a living. If something goes wrong, are we going to put a sample on the courier and send it to another country for sequencing? No. We need to be able to respond, prioritise and act quickly."
Source: www.stuff.co.nz; www.voxy.co.nz