This Arable Extra discusses the extent of herbicide resistance in weeds on arable farms in New Zealand based on the results of five years of random weed surveys.
Key points
- Herbicide resistance is widespread, with very high levels in some regions.
- All cases of resistant weeds were to herbicides in Mode-of-Action Groups 1 and 2.
- The most common species of resistant weed were from the Lolium (ryegrass) genus.
- The incidence of resistance varied between regions, from 11% to 71% of properties tested.