Australia
July 4, 2012
To avoid insecticide spray failures and prevent or delay the development of resistance, it is recommended that growers use a broad range of Integrated Pest Management (IPM) strategies.
Department of Agriculture and Food (DAFWA) entomologist Svetlana Micic said an IPM approach involved correctly identifying the problem insect pest; monitoring pest numbers; and assessing damage to crop plants.
Redlegged earth mites on canola
“Growers can also prevent spray failures by choosing control strategies based on economic thresholds; spraying only when necessary; and rotating insecticides across different chemical classes/modes of action,” she said.
More information about approaches to key insect pests of Western Australian cropping systems is available in the new Grains Research and Development Corporation (GRDC) Insecticide Resistance Management and Invertebrate Pest Identification Fact Sheet.
The timely resource is available in the July-August edition of the GRDC magazine Ground Cover and at www.grdc.com.au/GRDC-FS-IPM-SW
Ms Micic, who helped compile the fact sheet, warned that growers should avoid the use of prophylactic (insurance) sprays.
“’Insurance sprays’ can be an unnecessary cost and may speed up the development of insecticide resistance in pest populations,” she said.
“Growers should consider carefully the need for insecticides; there may be beneficial insects present that will help control pests if crops are left unsprayed.”
Ms Micic said high levels of insecticide resistance could cause significant financial and yield losses.
“Problem pests with resistance in WA include redlegged earth mites, diamondback moth and green peach aphids,” she said.
“Information about managing these potentially damaging pests is contained in the fact sheet, as well as information about IPM and how to put it into action.”
IPM tactics fall into the following categories:
• Cultural – such as crop rotations and weed control which can suppress pest populations;
• Chemical – spray only if you have to and favour those products that conserve pests’ natural enemies;
• Genetic – pest-resistant plant varieties;
• Biological – the conservation of natural enemies such as parasitic wasps, predators and pathogens that attack or feed on pests.
Species
