Getting the best out of Group A grass herbicides
Best use of Group A grass herbicides may result in more than 3-5 years effective life.
Misuse may result in resistance in 3-5 years and the loss of Group A mode-of-action for grass weed management (as has happened in Thailand, Vietnam and California).
The Group A mode-of-action is known to be high risk for resistance management (CropLife Australia).
- BARNSTORM and AURA are high risk for development of resistance in grass weeds.
- Integrated Weed Management (IWM) must be employed in all instances – use all other options first or together with Group A herbicides.
- Think diversity. Use as many tactics to reduce weed numbers as possible and use Group A herbicides as the last option, NOT the only option as this will fail.
- Weed seed production must be stopped every season. Survivors that set and shed seed will lead to more rapid onset of resistance.
- Using all the techniques available, Group A grass herbicides may be effective into the next decade, which will allow most efficient production of high value rice in Australia.
Greg Wells, R&D Leader Southern Australia, Dow AgroSciences, Greg Sefton, Senior Agronomist, IK Caldwell Malcolm Taylor & Agropraisals Pty Ltd, Rice Pre-season 2014