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EPA Guidance on Managing Pesticide Resistance

For Release: September 22, 2017

EPA has released two Pesticide Registration Notices (PRNs) aimed at combating pesticide resistance.

  • PRN 2017-1, “Guidance for Pesticide Registrants on Pesticide Resistance Management Labeling” offers general guidance on resistance management labeling for all conventional agricultural insecticides, fungicides and herbicides.
  • PRN 2017-2, “Guidance for Herbicide Resistance Management Labeling, Education, Training, and Stewardship” focuses specifically on herbicides and provides guidance on labels, terms of registration, education, training and stewardship.

Pesticides are used to control a variety of pests, such as insects, weeds, rodents, bacteria, fungi, etc. Over time, many pesticides have gradually lost their effectiveness because pests have developed resistance – which can be described as a significant decrease in sensitivity to a pesticide. Resistance reduces the utility of these pesticides. It has become a major economic factor in crop production and resulted in losses to growers.

To address the growing problem of resistance and preserve the useful life of pesticides, EPA has embarked on a more widespread effort aimed at helping pesticide users combat and slow this problem. Through these two PRNs the Agency is offering strategies to combat pesticide resistance. The two resistance management PRNs are available at EPA took comments on the documents from June – September 2016 and incorporated those comments into the final documents.  The Agency’s response to public comments will soon be available for each PRN at Docket# EPA-HQ-OPP-2016-0242 and Docket# EPA-HQ-OPP-2016-0226.

EPA is focusing first on holistic guidance for herbicides. Herbicides are the most widely used agricultural chemicals, and no new herbicide mechanism of action has been developed in the last 30 years, while herbicide-resistant weeds are rapidly increasing.  In the future, the Agency plans to evaluate other types of pesticides (e.g., fungicides, bactericides, insecticides and acaricides) to determine whether and what types of guidance may be appropriate for those types of pesticides.