Source: Syngenta news release

As more cases of glyphosate-resistant weeds are reported on new acres in the Corn Belt each year, growers are integrating resistance management into their production strategies. Increasingly, growers are discovering that solid resistance management programs can be agronomically sound in the long run and economical in the near term, as they find ways to get rewards immediately with higher corn yields and even cash incentives.

To achieve higher corn yields, growers are exploring their options with pre-emergence herbicides that help minimize early weed competition that can obstruct the way.

Bob Hartzler, extension weed specialist at Iowa State University, said, "An important component to resistance management is the use of alternative weed control chemistries, such as pre-emergence herbicides."

Richard Thooft, a grower in Lakefield, Minn. includes pre-emergence weed control as part of his AgriEdge Corn weed control strategy. He uses a full-rate of Lumax herbicide from Syngenta for early-season weed control and sprays Touchdown Total glyphosate herbicide on corn hybrids with the Agrisure GT trait if needed.

"Herbicide diversification is important, but to be fully effective at reducing selection pressure the alternative herbicides must control weeds at least as well as glyphosate," Hartzler said. "If weeds are not effectively controlled by the alternative herbicides, the likelihood of resistance appearing in these weeds would be just as great as if no pre-emergence herbicide had been applied."

By following his AgriEdge Corn weed control strategy, Thooft has been able to successfully control a wide spectrum of weeds, including lambsquarters, common ragweed and Canadian thistle.

"I also get a cash incentive as an additional bonus for following a recommended AgriEdge Corn weed control program," Thooft said.

The AgriEdge Corn Program is a crop management system that encourages growers to follow agronomic solutions that help maximize corn yield potential. Growers get cash incentives for selecting the best seed genetics, traits, seed treatment, herbicides, fungicides and insecticides from Syngenta.

To further manage resistance, Thooft makes it a point to rotate corn and soybeans so he limits dependence on glyphosate.

"After planting corn hybrids with the Agrisure GT trait in one year and planting NK Brand Soybeans with the Roundup Ready trait the next year, we'll switch to conventional corn the year after," Thooft said. "We also never plant glyphosate tolerant crops on the same field more than two years in a row."

Brent Woodman of Kenesaw, Neb. takes a similar approach.

"We use a full-rate of Lexar herbicide to minimize weed competition on the corn acres early in the season," Woodman said.

Like Thooft, Woodman also rotates corn and soybeans every year, planting corn hybrids with the Agrisure LL trait