Weeds Remember They Are Resistant
Once herbicide resistance develops, weeds remember that they are resistant.
When ALS herbicides were widely used to control waterhemp in the early 1990s, ALS-resistant waterhemp soon followed. Luckily, glyphosate-tolerant technology soon became available to the market to relieve pressure on ALS-resistant weeds. As glyphosate-resistant waterhemp begins to appear more frequently, those populations have not forgotten they're resistant to ALS herbicides as well. Resorting to old chemistries may not be an option, or limits options.
Multiple resistance to herbicides makes weed management that much more complicated. It also encourages the need for use of multiple modes of action.
As future generations develop, the resistance trait doesn't disappear. This underscores the importance of a proper weed management program to keep resistant weeds off of your fields.
Syngenta recommends:
- Using a pre-emergence residual herbicide in glyphosate-tolerant crops
- Choose herbicides or tank mixes with multiple modes of action
- Rotate crop and herbicide systems
- Use full herbicide rates
- Scout fields and develop a multiyear weed resistance management plan
What does your weed management plan entail? How has it changed with the development of resistant weeds? What tips do you have for other growers?
To read more about best management practices, check out the Resistance FighterTM Best Practices technical bulletin.
Read Resistance to Multiple Herbicides a Growing Challenge to learn more about multiple resistances.