Cotton and soybean farmers in 19 counties in northeast Arkansas have a better than 50 percent chance of encountering PPO-inhibitor resistance in Palmer amaranth in their fields in 2017, according to University of Arkansas weed scientists.
Jason Norsworthy, professor of weed science at the University of Arkansas System Division of Agriculture, gave that assessment during his opening remarks at this year’s Pigposium 3 in Forrest City, Ark.
Dr. Norsworthy said PPO inhibitor resistance is developing in much the same way that resistance developed to glyphosate herbicide following the discovery of glyphosate-resistant pigweed in south Georgia in 2005.
“That means that the world’s best herbicide is no longer effective against Palmer amaranth in most of the state,” said Dr. Norsworthy, one of the organizers of the Pigposium 3, which was attended by more than 300 producers, university and Extension personnel at the East Arkansas Community College Campus in Forrest City.
With the widespread flooding that has occurred across northeast Arkansas and the expected rise in the Mississippi River in the days ahead, that’s expected to make 2017 another challenging year for Arkansas producers.
To watch other video from Dr. Bob Scott’s presentation at Pigposium 3, click on http://www.deltafarmpress.com/cotton/replacing-one-herbicide-another-resistance-treadmill snf