U.S. EPA to require herbicide resistant management plans

During a recent meeting of the National Research Council, which is conducting a study examining genetically engineered (GE) crops and food, an Environmental Protection Agency official described the agency's new precautions for Dow AgroScience's Enlist Duo product, the first herbicide for which EPA requires a weed resistance management plan.

Bill Jordan, deputy director at EPA's Office of Pesticide Programs, noted that the agency is imposing new obligations on the company, and "if it does not follow through EPA has the legal authority to terminate the registration," which EPA approved in October.

Enlist Duo, a dual herbicide that includes a blend of glyphosate and 2,4-D choline, is part of the Enlist Weed Control System, a herbicide-tolerant trait technology for corn and soybeans. The herbicide will be launched in conjunction with the stewarded introduction of Enlist corn and seed production of Enlist soybeans in 2015.

"Continued registration of Enlist will depend on successfully controlling herbicide resistant weeds," according to EPA's evaluation. The registration will expire in six years, when EPA will review the management plan's results. In the future, any herbicide products for use on tolerant crops will fall under similar EPA programs.

EPA's terms of registration require the company to:

*Develop a stewardship program and training programs and educational materials for users.

*Investigate cases of non-performance.

*Develop remediation plan for use if resistance is expected (Dow must take steps to control and prevent the spread of likely resistant weeds, and thorough follow up is expected to make sure a problem is addressed.)

*Report annually to EPA likely and confirmed resistance (This must include enough information to describe the nature and extent of infestation. Also, EPA says early notification is important to allow time to respond to the problem.)

A Dow spokesperson said all of the elements included in EPA's registrant requirements are new.

"With regard to our Enlist system, putting together a comprehensive stewardship program was front and center as we developed our plans over the last several years," Dow stated. "We worked with the EPA to refine and develop a herbicide resistance management plan acceptable to stakeholders."