A minute wasp around 0.5mm long could help protect Australia's billion dollar sorghum industry, according to an experienced Queensland entomologist.
Toowoomba-based Bugs For Bugs director and entomologist Dan Papacek has called for growers impacted by fall armyworm to limit chemical sprays and consider biological controls to battle the invasive pest.
Mr Papacek said research into the wasp species Trichogramma Pretiosum undertaken by DAF senior entomologist Dr Melina Miles, showed how a number of factors including an integrated approach which maximised the benefits from biological controls while limiting the use of harmful and disruptive chemicals could help reduce the FAW threat.
"I have always had a close working relationship with DAF and the universities and we were acutely aware when FAW came into Australia," Mr Papacek said.
"At the time this wasp was used to target Heltiothis (Helicoverpa spp.) which was a very significant pest of cotton, sweetcorn and pulse crops.
"We were aware this species had potential against FAW shown by some of the work done by DAF and by Dr Miles who identified this parasitoid was a potential agent to control FAW."
A parasitoid lays its eggs in FAW eggs and eventually killed the host they fed on, Mr Papacek said.
He said the adult female laid her eggs into moth eggs and when the wasp eggs hatch, the larvae devoured the developing caterpillar inside the moth egg.
After the Trichogramma larvae pupate and grow into fully formed wasps inside the moth eggs, they emerge by chewing a hole in the moth egg and can then parasitise other moth eggs.
This process takes from seven to 10 days, depending on temperature and a female wasp can parasitise over 50 moth eggs during her lifespan of up to 14 days.
"Parasitoids can help keep the pest population below a damaging threshold," Mr Papacek said.
"These things are never a silver bullet but are part of a suite of management practices."
The collected wasps produced from eggs which attacked FAW in the field which were then used to mass-produce the species at their Toowoomba facility so growers can use them to help manage the pest.
"There are certain other practices to help growers over the line when dealing with FAW," he said.
"Biodiversity is always a good thing, so having refuges for biocontrol agents in amongst or nearby crops is important.
"At this stage we are at the cusp or point where I see more interest in this alternative to using chemicals as up to now when a new invasive species turned up, growers saw spraying as the answer.
"But it's not always easy to get the coverage you require and you often wind up with a secondary outbreak."
According to the Bugs For Bugs website the wasps cost between $31.90 to $73.15 depending on the quantity and are supplied as a sheet of 60 individual release capsules which totals 60,000 wasps per sheet.
Mr Papacek likened grower reliance on often harmful chemical sprays to human over-use of antibiotics.
"No-one would dispute antibiotics have not been beneficial but poor decisions have led to its overuse which has caused a lot of resistance making it less effective," he said.
"At Bugs for Bugs which I founded 40 years ago we specialise in integrated pest management to help Australian growers achieve best practice pest management with the least possible pesticides."
Mr Papacek's business operates three insectary sites located at Mundubbera, Donnybrook and Toowoomba, which comprises around 75 constant temperature controlled rooms and 28 greenhouse structures.
He said they work with a wide range of industries in agriculture, horticulture and with intensive animal operations such as piggeries and chicken farms.
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