New Resistance Web Sites Launched

Monsanto and Syngenta create Web sites to promote management of glyphosate resistance. Jacqui Fatka

Published on: Oct 3, 2005

Glyphosate resistance is making the headlines again with news that pigweed in two Tennessee fields and waterhemp in Missouri may be resistant to glyphosate. As a way to continue to educate growers on how to prevent resistance from occurring, both Monsanto and Syngenta have launched interactive Web sites to help with the fight.

"Glyphosate resistance is a real and growing threat," says Chuck Foresman, Herbicide Resistance Technical Brand Manager for Syngenta Crop Protection. "Just this month, a fifth weed in the United States, Palmer pigweed, officially joined the ranks of resistant weeds. In only seven years, researchers have confirmed glyphosate resistance in 14 states."

Monsanto's Web site,, offers a new fact-based resource for the agriculture industry and provides tips for managing weed resistance from a variety of experts in the agricultural community, including weed scientists, crop advisors, growers, retailers and industry leaders.

The Web site defines weed resistance and how it can occur, gives the facts on where resistance has happened and provides growers with the best practices to manage weeds on their farm, according to Doug Rushing, Director of Technology Development for Monsanto. Some features of the site include management recommendations for specific tough-to-control weeds, localized information for growers by region, recent news and updates, and information on how to determine whether a resistant weed is present in the field. In particular, the site offers tips for weed control in all of the Roundup Ready systems.

To confirm resistance, a grower must no longer be able to control a weed species with the labeled rate and it passes on to the next generation, explains Greg Gilmore, Monsanto soybean technical manager. Gilmore explains that in the case of the Tennessee declared glyphosate resistance of Palmer pigweed, heritability tests had not been run to determine if the resistance passes on to the next generation.

The best way to achieve weed control is by starting with a clean, weed-free field and keeping it clean throughout the season. That's the essence of Start Clean, Stay Clean and the advice offered on the Web site. Developed with input and guidance from weed scientists, the site offers these fundamental tips:

  • Start with a clean field by controlling weeds early.
  • Use Roundup Ready technology as the foundation of your weed management program.
  • Add other herbicides and cultural practices where appropriate as part of the Roundup Ready system.
  • Use the right herbicide rate at the right time.
  • Control weeds throughout the season and reduce the weed seed bank.

These tips are available on, along with specific tips for Roundup Ready corn, soybeans, cotton, canola and alfalfa.

At Syngenta's, growers, researchers and industry leaders can participate in the online forum, ask questions, see where resistance is occurring and read the latest articles on glyphosate resistance. However, the main goal of the site is to offer solutions for delaying and managing resistance.

"The Resistance Fighter code for effective management is 2-1-2: no more than two applications of glyphosate on one field over a two-year period," Foresman says. "We know that with glyphosate-tolerant crops, it's possible for growers to use nothing but glyphosate year after year. That's short-term thinking. Growers really need to consider that once glyphosate-resistant weeds develop, they don't go away. Weeds remember they are resistant to glyphosate for years. Plus, there is no new chemistry coming along so we need to preserve the tools we have today for future generations."

Do you 2-1-2? To become part of the Resistance Fighter movement, log on to and click on the laptop to register.