What Herbicide-resistant Traits Mean for Herbicide Resistance

In a recent article published in Farm & Ranch Guide, Iowa State University Extension Weed Specialist Bob Hartzler makes an interesting statement about the relationship between herbicide-resistant traits and herbicides.

While some new chemicals will come to the market this season, there are several herbicide-resistant traits to be offered in the near future.  Hartzler says the introduction of these herbicide-resistant traits is a sign that there aren’t many new herbicide options in development.

Many growers feel that, as has happened in the past, chemical companies will come out with a new herbicide, or new chemistry to alleviate the current resistance problem. For example, when ALS-resistant waterhemp increased in Midwest fields in the mid-1990s, glyphosate-tolerant soybeans were introduced to the market. Now that glyphosate-resistance is becoming a larger issue, some feel the next silver bullet is just over the horizon. Unfortunately, as Hartzler points out, there are plenty of indications that cultural methods and existing herbicides need to be utilized to the best of our ability.

Companies like Syngenta are still investing in research to develop new herbicide modes of action, but the easy ones have already been found. Even if a new herbicide were to be developed today, it generally takes 10 years and $200 million to bring it to market. The last new modes of action developed were:

• For soybeans: Glufosinate, or Liberty®, in 1994
• For corn: HPPD-inhibitors, such as isoxaflutole (Balance®) in 1998 or mesotrione (Callisto®) in 2001

For crop-specific resistance management recommendations, visit the Syngenta Resistance Fighter™ library. Or to develop your own specific management program, visit the Resistance Fighter Resistance Management Solutions Module at www.resistancefighter.com/solutions.

Callisto® and Resistance Fighter™ is a trademark of a Syngenta Group Company. Balance® and Liberty® are registered trademarks of Bayer CropScience.