Since 2022, an insecticide resistance surveillance program for fall armyworm (FAW) has been conducted annually by NSWDPIRD in collaboration with DAF entomologists.
Resistance to older products, such as carbamates (Group 1A), organophosphates (Group 1B) and pyrethroids (Group 3A) has been confirmed in many FAW populations worldwide, and there are concerns that the increase in spraying to control FAW may lead to an increase in resistance levels in this pest (and others) to products commonly used in Australian production systems.
Thousands of samples have been processed to date, and the good news is that genes for resistance to chlorantraniliprole, emamectin benzoate, spinetoram and indoxacarb are still extremely rare in Queensland fall armyworm populations, meaning that these products should continue to provide effective control of fall armyworm.
However, the risk of resistance developing is still present, so always follow resistance management recommendations such as the Helicoverpa Resistance Management Strategy when choosing products to apply to your fields.
General principles to minimise resistance development include:
- Monitor pest and beneficial populations regularly, using appropriate sampling techniques.
- Correctly identify the pest to ensure the most effective insecticide and rate is used.
- Assess the beneficials present to determine if chemical control of the pest is warranted.
- Consider the impact on all species present when selecting insecticide sprays.
- Avoid prophylactic sprays, and use economic thresholds (if available) when making spray decisions.
- Use target-specific ‘soft’ chemicals rather than broad-spectrum pesticides where possible and avoid repeated use of insecticides from the same mode of action.
- Read carefully and comply with all directions on product labels – DO NOT cut rates or exceed the recommended applications per crop per season.
- Calibrate spray rigs regularly to ensure effective coverage.
- Monitor post-treatment for evidence of loss of field efficacy and report field failures. If a spray fails due to resistance or unknown cause, do not re-spray with that group again in the same season.
See the fall armyworm resistance surveillance page for a regional breakdown of testing results.