A FUNGAL disease, which wiped out $10 million in onions nearly 20 years ago, could be to blame for massive write-downs in sections of this year’s Tasmanian crop.
The Tasmanian Farmers and Graziers Association (TFGA) vegetable committee chairman Nathan Richardson said some suppliers of exporter Field Fresh, at Forth, had between a third and three quarters of their crop written off.
In 1996, entire shipments of onions to Europe were written off, after being infected by botrytis neck rot, Metcalf Biological Control plant biologist Dean Metcalf said.
“Certainly, there is some botrytis neck rot, around this year,” Mr Metcalf said.
“The problem begins with the planting of infested seed, they work hard to avoid using invested seed now – but if you plant a seed that has the disease that will grow into a bulb that will rot.
“Not only will it do that, it will create spores that will spread around it and it will take another 100 plants with it,” he said.
Neck rot was the biggest problem in the history of the Tasmanian onion industry.
“In 1996, there was an export disaster - $10 million of onions rotted on the way to the European market,” Mr Metcalf said.
“The disease makes one hell of a mess,” he said“
Field Fresh produced around 20 per cent of Australia's onion crop and this year exports went to 14 countries.
The company was very proactive in trying to stop neck rot in onion crops, Mr Metcalf said.
Mr Richardson said botrytis was being investigated as to one of the causes of the high level of rejection of onions by Field Fresh.
“We are also talking about the possibility that maybe it’s an in field problem, but we just don’t know,” Mr Richardson said.
“The farmers, rightly so, are concerned and if it’s a variety based issue, or its an agronomic issue, or seasonal issue, that’s reallywhat we need to decipher.
“Field Fresh know their onions pretty well, and I am sure – between us, the company and the growers, we will get a pretty good idea of what is going on.”
Growers would meet with Field Fresh soon.
“In any given year crops of onions might suffer from abnormalities, in terms of the scale of this it’s a bit little unusual,” Mr Richardson said.
The managing director of the other big onion processor, Harvest Moon, Neil Armstrong, said botrytis issues did not seem to be affecting the vegetables supplied to him.
Harvest Moon was a different business, with a different model, to Field Fresh, he said.
“There are a couple of issues, but we’ll work around them, we’ve had a reasonable season,” he said.
Mr Metcalf said Field Fresh watched its costs very closely.
“I doubt it’s a lack of spray programs, weather events, or mutation in the strain of the disease – I doubt it’s the fault of the agronomists, giving herbicide advice, they are very rigorous,” Mr Metcalf said.
“There is no other company that has put a greater effort into managing this disease, they are the ones who have the most to lose.
“They really have been proactive in trying to manage it in a geographic region that is predisposed to the disease.”
Neck rot is known for causing onions to rot in storage, in cooler states like Tasmania and Victoria.
It is caused by the fungus botrytis allii, which enters crops through infected seed.
The disease spreads during the growing season, especially in humid weather.
There are no fungicide seed dressings which are proven to eradicate botrytis from onions.
