Take the test for herbicide resistance

Published: 4 Jul 2013

Image of Take the Test for Herbicide Resistance GRDC Fact Sheet

Knowing which herbicide modes of action (MOA) are still effective can avoid in-crop herbicide failures and allow growers to develop long term weed management plans

Key points:

  • Wild radish is the most problematic weed on the sandplain soils of the northern wheatbelt.
  • Multiple resistance to commonly used selective herbicides is increasing in local wild radish populations.
  • Incidence of annual ryegrass with Group A (diclofop), Group B, Group D (trifluralin) and multiple herbicide resistance continues to increase across the northern wheatbelt.
  • Clethodim (Select®) has had the biggest increase in annual ryegrass resistance levels since 2003 and there is now resistance to high label rates in the northern wheatbelt.
  • Testing wild radish and ryegrass populations to assess herbicide resistance status can ensure effective herbicides are applied in-crop and results can be used to help develop management strategies.
  • Glyphosate effectiveness, especially, can be protected by monitoring resistance after spraying and using integrated weed control tactics.
  • Multiple non-herbicide and herbicide strategies are required within each cropping season to prevent weed and weed seed blow-outs.
  • Always use recommended label rates of herbicides to slow the evolution of herbicide resistance and prolong herbicide efficacy.

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GRDC Project Code UWA00146, UA00124, DAW00196,DAW00218, DAW535, UWA00124,UQ00062

Region West, North, South

Region: West; North; South

GRDC Project Code: UWA00146, UA00124, DAW00196,DAW00218, DAW535, UWA00124,UQ00062