University of Queensland researchers in collaboration with industry have developed a "green" pesticide for the caterpillar stage of the Heliothis moth (Cotton Boll Worm) - the biggest insect pest in the world.
In a multi-million dollar project led by Chemical Engineering Department lecturer and director of fermentation technology Dr Steven Reid, researchers are perfecting a fermentation process for the biopesticide with its sale to rural producers estimated to be only two years away.
In the fermentation process, the insect's cells are grown in liquid culture in a series of stainless steel tanks or fermenters kept at 28 degrees Celsius.
Once cells have reached a sufficient density, a naturally occurring virus, Heliocoverpa armigera, is added. Culture and cell debris are then filtered and dissolved out of the liquid leaving a concentrated virus ready for sale and dilution to farmers. It is sprayed on crops from tractor or light aircraft.
"The Heliothis caterpillar affects most crops including cotton, sorghum, chickpea and various vegetables. It costs producers billions of dollars world-wide each year to control the insect using conventional chemicals," Dr Reid said.
"The advantage of using this natural pesticide is that it is specific only to the Cotton Boll Worm and will not affect anything else."
Dr Reid said a key to the team's leading edge was the modern approach to biological engineering taken at the Chemical Engineering Department under the leadership of senior lecturer Dr Lars Nielsen. Field trials of the biopesticide by industry partner Agrichem and the Queensland Department of Primary Industries began in late 1999 on chick pea/sorghum, cotton and tomato crops in the Darling Downs and parts of New South Wales.
Agrichem managing director Frazer East said it was testimony to the success of the collaboration that a Queensland company and a Queensland university on a shoestring budget could achieve what three multinationals spending an estimated $450 million could not.
"It is imperative that an alternative to chemical pesticides is made available because of rising resistance to existing sprays by the caterpillar. In desperation, some farmers are mixing their own chemical cocktails to try to overcome the resistance at great expense but even this effort is failing to provide adequate control," Mr East said.
For more information, contact Dr Steven Reid (telephone 07 3365 4001) or Frazer East (telephone 07 3801 4888).
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