Rapid spread of glyphosate-resistant weeds spurs new initiative: Respect the Rotation

In light of rapid expansion of glyphosate-resistant weeds, a cross-section of weed management, tillage and agronomy experts met to discuss an initiative designed to protect weed control options for years to come.

The initiative, called Respect the Rotation, is being facilitated by Bayer CropScience and is intended to spur grower adoption of the key elements of Integrated Weed Management (IWM), said Andy Hurst, product manager for Bayer, which served as host for two days of field tours and roundtable discussions.

"A key goal is to preserve the utility of glyphosate herbicide and promote proper stewardship of viable technologies, such as the LibertyLink(R) trait and Ignite(R) herbicide," Hurst said. "Respect the Rotation provides the opportunity for an open dialogue to help define how the industry can work comprehensively to support and act upon the messages the weed science community has championed for years."

By incorporating the principles of IWM, growers can work to stem the tide of resistance before agriculture practices are irrevocably changed. Greater numbers of growers are feeling the economic pinch as burgeoning glyphosate resistance leads to reduced yields or even abandoned fields.

David Shaw, featured speaker and chair of the Herbicide Resistance Education Committee for Weed Science Society of America, underscores the need for new weed management strategies.

"At this point, glyphosate resistance is a reality," Shaw said. "Our challenge now is to take steps -- to adopt specific practices -- that will slow the spread of resistance and possibly extend the lifespan of glyphosate. An Integrated Weed Management strategy will accomplish those objectives."

A main barrier, according to Shaw, is the mistaken perception that adopting resistance management practices will cost growers more. However, Shaw said studies show just the opposite is true.

In a four-year research project under way in six key agricultural states (Illinois, Indiana, Iowa, Mississippi, Nebraska and North Carolina), researchers are comparing the economics of university-recommended, herbicide resistance management programs with the use of glyphosate as an exclusive treatment for weed control. As of the end of the third year of the study, researchers say the net returns on fields managed according to recommended practices are equal to or greater than the returns on those where glyphosate is used alone. Increased yields appear to offset any increase in herbicide costs.

With adoption of IWM, growers can better steward weed management technology, preserve conservation tillage opportunities, and promote sustainable and profitable row crop production.

"Respect the Rotation highlights the importance of rotating crops, use of advanced tillage methods, rotating herbicide modes of action and other management choices that positively impact weed-resistance management," Hurst said. "We want this event to be an impetus for increased focus, effort and attention by the ag community in gaining improved grower adoption of practices that will enable growers to avoid or manage weed resistance effectively and sustainably."

More than 200 attendees joined the event, representing the weed science community, consultants, growers, agribusiness, grower associations and organizations, and federal agencies.

This event was a natural next step following the Pan American Weed Resistance Conference hosted by Bayer CropScience in January. There, weed science community participants defined the scope of weed resistance development and discussed the need to motivate grower adoption of IWM practices.

SOURCE: Bayer CropScience