Published Tuesday, 10 July, 2007 at 12:28 PM
Minister for Primary Industries and Fisheries
The Honourable Tim Mulherin
VEGETABLE GROWERS BACK WASP TO BEAT FLY
Rockhampton district vegetable growers have welcomed the release of 30,000 parasitic wasps which they hope will put the brakes on the escalating and damaging impact of silverleaf whitefly.
Department of Primary Industries and Fisheries senior horticultural extension officer Eric Coleman coordinated the wasp release into commercial pumpkin, zucchini and sweet potato crops in the Gracemere, The Caves and Rossmoya districts.
Minister for Primary Industries and Fisheries Tim Mulherin said the silverleaf whitefly incursion had been a problem in Queensland since 1996 and during peak plagues in 2000 and 2004, vegetable growers reported crop losses of up to 70 per cent.
“While we have a few Australian native parasitic wasps that parasitise on silverleaf whitefly nymphs, their parasitim rate peaks is at around 20 per cent whereas the imported Eretmocerus wasp has a far more vigorous 50-80 per cent impact,’’ Mr Mulherin said.
“This is just another example of our dedicated DPI&F staff examining ways to do things better for the benefit of industry.’’
A DPI&F entomology team at Bowen Dry Tropics Research Station led by Dr Siva-Subramaniam has successfully bred colonies of the tiny parasitoid Eretmocerus wasp that originated from Pakistan and was then imported via the US by CSIRO.
“This Rockhampton release is part of an industry-funded $500,000 project exploring integrated pest management (IPM) techniques to control SLW that presents a real threat to the viability of Queensland’s $700M vegetable industry,” Dr Subra said.
“Our research priorities are to develop IPM strategies for key vegetable crops and gauge the ability of Eretmocerus wasps to effectively control SLW in conjunction with IPM friendly “soft” chemicals that do not kill beneficial insects.
“Because the SLW life cycle from egg to adult takes place in just 18 to 28 days, the parasitism of the nymphs by the wasps needs to keep pace with the rapid increase of the SLW population.
“Inappropriate use and over reliance on insecticide formulations can lead to SLW developing resistance to insecticides so growers are urged to work cooperatively to develop insecticide resistance management strategies,” Dr Subra said.
Mr Coleman said cotton growers in southern and Central Queensland have successfully adopted area-wide SLW control strategies to maximise the longevity of new “soft” chemical formulations.
In contrast to implementing area-wide spray control programs for field crops such as cotton, soybeans and navy beans, developing area-wide insect resistance management strategies for the diversified vegetable industry presents a real challenge.
Mr Coleman said sample material had been collected from Rockhampton district vegetable crops to benchmark the current level of native predatory wasp species.
“In late July to November, follow-up sampling will be undertaken to determine the success of the Eretmocerus wasp release and its impact of the SLW population.”
Mr Coleman said the cooperation of vegetable growers, consultants, chemical companies and insecticide resellers was vital to preserve the long term efficacy of IPM friendly insecticides.
Mr Coleman said the Eretmocerus wasp was the biological key to effectively managing SLW and addressing production losses in combination with the strategic use of these new chemicals, good farm hygiene and best management practice.
Media Minister’s office: 323 96530
Media Department: Regional Media Officer Russ Boadle: 0418 789 939
Photograph available on request.
Department of Primary Industries and Fisheries senior horticultural extension officer Eric Coleman coordinated the wasp release into commercial pumpkin, zucchini and sweet potato crops in the Gracemere, The Caves and Rossmoya districts.
Minister for Primary Industries and Fisheries Tim Mulherin said the silverleaf whitefly incursion had been a problem in Queensland since 1996 and during peak plagues in 2000 and 2004, vegetable growers reported crop losses of up to 70 per cent.
“While we have a few Australian native parasitic wasps that parasitise on silverleaf whitefly nymphs, their parasitim rate peaks is at around 20 per cent whereas the imported Eretmocerus wasp has a far more vigorous 50-80 per cent impact,’’ Mr Mulherin said.
“This is just another example of our dedicated DPI&F staff examining ways to do things better for the benefit of industry.’’
A DPI&F entomology team at Bowen Dry Tropics Research Station led by Dr Siva-Subramaniam has successfully bred colonies of the tiny parasitoid Eretmocerus wasp that originated from Pakistan and was then imported via the US by CSIRO.
“This Rockhampton release is part of an industry-funded $500,000 project exploring integrated pest management (IPM) techniques to control SLW that presents a real threat to the viability of Queensland’s $700M vegetable industry,” Dr Subra said.
“Our research priorities are to develop IPM strategies for key vegetable crops and gauge the ability of Eretmocerus wasps to effectively control SLW in conjunction with IPM friendly “soft” chemicals that do not kill beneficial insects.
“Because the SLW life cycle from egg to adult takes place in just 18 to 28 days, the parasitism of the nymphs by the wasps needs to keep pace with the rapid increase of the SLW population.
“Inappropriate use and over reliance on insecticide formulations can lead to SLW developing resistance to insecticides so growers are urged to work cooperatively to develop insecticide resistance management strategies,” Dr Subra said.
Mr Coleman said cotton growers in southern and Central Queensland have successfully adopted area-wide SLW control strategies to maximise the longevity of new “soft” chemical formulations.
In contrast to implementing area-wide spray control programs for field crops such as cotton, soybeans and navy beans, developing area-wide insect resistance management strategies for the diversified vegetable industry presents a real challenge.
Mr Coleman said sample material had been collected from Rockhampton district vegetable crops to benchmark the current level of native predatory wasp species.
“In late July to November, follow-up sampling will be undertaken to determine the success of the Eretmocerus wasp release and its impact of the SLW population.”
Mr Coleman said the cooperation of vegetable growers, consultants, chemical companies and insecticide resellers was vital to preserve the long term efficacy of IPM friendly insecticides.
Mr Coleman said the Eretmocerus wasp was the biological key to effectively managing SLW and addressing production losses in combination with the strategic use of these new chemicals, good farm hygiene and best management practice.
Media Minister’s office: 323 96530
Media Department: Regional Media Officer Russ Boadle: 0418 789 939
Photograph available on request.