Development of Dow Agrosciences' EnlistTM Herbicide Tolerant Trait In Soybean.

A synthetic gene (AAD12) derived from Delftia acidovorans was developed by Dow AgroSciences and the gene is being developed as a component of the Enlist weed control system.   The gene was introduced into soybean (Glycine max L.) via Agrobacterium tumefaciens mediated transformation. In planta this gene produces an enzyme that deactivates several herbicides having an aryloxyalkanoate moiety, including phenoxy auxins (e.g., 2,4-D, MCPA) and pyridyloxy auxins (e.g., fluroxypyr, triclopyr).  In this presentation, we describe soybean event sorting, introgression, and event characterization at the DNA structural level and protein expression level.  We have selected several high quality, efficacious, and single copy events with the transgene inherited as a Mendelian dominate trait. Transgene expression has been stable across twelve generations.  Multi-location yield trials showed that the soybeans containing selected events had no significant injury or yield loss from 2,4-D spray rates up to 2240 g ae/ha.  In unsprayed trials, the yield of soybeans containing selected events was no different than iso-lines across multiple seasons (2008- 2010).