Triple Mode of Action Herbicide Tolerance Utilizing the Enlist™ Weed Control System in Soybeans.

Triple Mode of Action Herbicide Tolerance Utilizing the Enlist™ Weed Control System in Soybeans

Malcolm Obourn¹, Greg Bradfisch¹, Cory Cui¹, Bill Eby², Bruce Held², Thom Hoffman¹, Justin Mason², Dayakar Pareddy¹, Mark Peterson¹, Sean Russell¹, Vaithilingam Sekar², David Simpson¹, Angie Umthun², Terry Wright¹, and Zhanyuan Zhang³

¹Dow AgroSciences, Indianapolis, IN, ²M.S. Technologies, West Point, IA and ³University of Missouri, Columbia, MO

Overview:

The Enlist™ Weed Control System was developed to provide superior options to growers to control their weed challenges including weeds with innate tolerance or developed resistance to glyphosate.  Specifically, Enlist traits enable the use of 2,4-D and glyphosate combinations in herbicide tolerance cropping systems.  Combinations of 2,4-D and glyphosate showed excellent control for weed biotypes glyphosate did not control.

The Enlist E3™ soybean trait was designed to convey herbicide tolerance to 2,4-D, glyphosate and glufosinate in a single T-DNA unit.  Crop tolerance to these herbicides has been demonstrated in predecessor traits.  However, Enlist E3 soybeans (or event DAS-44406-6) is the first trait to have 3 genes for herbicide tolerance segregating as a single locus.

DAS-44406-6 demonstrated consistent expression of all three herbicide tolerance proteins.  The yield of soybean varieties containing DAS-44406-6 was indistinguishable from isogenic null segregates.  DAS-44406-6 demonstrated robust tolerance to 2,4-D, glyphosate and glufosinate.  Even at high application rates, soybean yield was equivalent to untreated controls.