A DISPARATE and piece-meal approach to managing pests needed to be replaced with national systems that were adaptable to new and existing incursions.
That was the view of attendees at a vegetable industry update on Tomato Potato Psyllid, held at Clyde recently.
The TPP aphid affected a range of vegetable crops in the Solanaceae family including potato, tomato, eggplant, capsicum, chilli, tamarillo and sweet potato.
In New Zealand, where it was first detected in 2006, TPP is considered one of the most destructive potato pests in the western hemisphere.
Surveillance and diagnostic resources of the Department of Agriculture & Food WA (DAFWA) have been focused on identifying that Candidatus Liberibacter solanacearum (CLso), a bacteria TPP can carry in their gut and is associated with ‘zebra chip’ in potatoes, is not present in Western Australia.
The aphid’s secretions helps turn starch to sugar in the plant, creating the ‘zebra chip’ look when the potato is cooked.
As of December 2017, no CLso had been detected in WA, using sticky traps.
However, State governments across Australia reiterated their biosecurity policies restricting movement of plant product from Western Australia. Queensland’s Department of Agriculture and Fisheries reiterated restrictions in a Movement Control Order, effective on August 11.
A WA biosecurity officer discovered the TPP pest in their backyard in February last year.
Since then, a quarantine area notice remains in place on more than 70 backyard and commercial properties in the greater Perth district. After the first discovery, a commercial capsicum crop north of Perth was implicated with the discovery of TPP.
WA growers and seed and seedling producers have been unable to export their product into eastern states.
Second-hand agricultural machinery and used packaging was also restricted from being moved across WA’s borders.
A national directive – that the pest cannot be eradicated – has led to several responses that aim to manage TPP.
The Commonwealth government has developed the Plant Quarantine Pest and Official Control National Policy – this places the onus of action, in the event of an incursion of exotic pest or plant, on control measures being implemented by Chief Plant Health Managers employed by State and Territory governments.
Under the policy, official control can also be implemented by a national approach (see http://www.outbreak.gov.au/prevent-and-prepare-for-outbreaks/official-control-quarantine-plant-pests-diseases), which would focus on measures to assure international trading partners that Australia had the disease or pest under control.
WA’s Minister for Agriculture and Trade, Alannah MacTiernan, told ABC radio that national biosecurity protocols needed to be better prepared, rather than driven by a state-by-state or ad-hoc response.
She was concerned that biosecurity decisions were being made based on scientific information that was out-of-date.
Her view was reinforced by a cross-section of potato industry representatives at Clyde recently, at a workshop where government extension officers and other scientists talked about the need to rapidly to gain what knowledge they could about TPP from overseas partners.
Ausveg’s national manager – science and extension, Jessica Lye, likened the response to TPP to that applied against cucumber green mottle mosaic virus in 2015 and 2016.
“The ideal program is a T2M – transition to management – phase,” Dr Lye said.
“The cucumber virus did not have a T2M, so quarantine continued for another year longer than necessary.”
T2M was an industry/government cost-sharing program, with 80 per cent of funds from government – State and Commonwealth – and 20pc from affected industry.
“Levy funds are normally expended and recouped in the future to repay the 20pc,” Dr Lye said.
“A T2M runs for 12 months so long as a response plan, with cost sharing arrangements, is in place.”
It also supported Australian growers’ return to trade, within and without the country.
Science needed to be applied against any compliance program, Dr Lye said.
There also needed to be one lead agency, for which Dr Lye nominated Ausveg.
“This is a national problem. We don’t know what our pathway into Australia is, for TPP – we’d like to know so we can close it,” she said.
“We’re in a national T2M phase, but States also have their own responses – in Victoria, the chief plant officer leads the response, makes recommendations to a committee; if that committee agrees, that recommendation goes up the scale,” she said.
“But, the individual State response can be a different action to the national response.
“This is a national problem that needs a national response. I talk to growers all around the country. The Commonwealth is talking about a national surveillance program; we’d like to get that up and running.
“And we need to appoint a TPP extension coordinator, responsible for liaising with State and Commonwealth governments and industry,” Dr Lye said.
“Growers need to know there is one person they can contact to find out what they need to know.”
A major consideration for industry was that early generational material produced during quarantine could still be recognised.
Dr Lye suggested onfarm biosecurity planning should be led by industry, with an auditable scheme applicable across Australia.
Adding privately-employed agronomists into the surveillance mix would benefit industry.
Agronomist Ruaan Du Plessis, with IK Caldwell, Shepparton, said an industry approach should utilise the network of private agronomists to help with the workload of information dissemination, crop monitoring and helping growers to develop biosecurity plans.