Weed resistance to herbicides is a global problem, which usually results from the repeated use of herbicides with the same mode of action. Simply said: “Weeds just got used to that mode of action and cannot be killed with that mode of action anymore.” Similar phenomenon is observed in medicine with disease resistance to antibiotics.
The Good is that these new phenoxy herbicide formulations will help control tough broadleaf weeds, including resistant and difficult-to-control weeds in Xtend and Enlist soybeans.
The Bad is that if not used with a weed management plan, we could quickly lose these new formulations to weed resistance.
Dicamba- and glyphosate-resistant soybean, also known as Roundup Ready 2 Xtend soybean, became commercially available for the 2017 growing season. About 500,000 acres were planted with Xtend soybean in Nebraska in 2017 growing season. Three dicamba-based herbicides — XtendiMax, FeXapan, and Engenia — are labeled for application in Xtend soybean.
