Author(s)

Laura Ford¹, Nader Soltani^1*, Darren E. Robinson¹, Robert E. Nurse², Allan McFadden³, Peter H. Sikkema¹

¹University of Guelph Ridgetown Campus, Ridgetown, Canada.
²Agriculture and Agri-Food Canada, Harrow, Canada.
³Dow Agrosciences, Guelph, Canada.

The 2,4-D choline/glyphosate DMA formulation has reduced drift and volatility compared to the amine or ester formulation of 2,4-D and therefore is advantageous compared to a tank mix of 2,4-D amine or ester with glyphosate. The objective of this research was to compare the control of glyphosate susceptible and glyphosate resistant Canada fleabane with 2,4-D choline/glyphosate DMA with 2,4-D amine, glyphosate, and a tank mix of 2,4-D amine and glyphosate. Ten rates of 2,4-D amine (0 - 6708 g·ae·ha^-1), glyphosate (0 - 7052 g·ae·ha^-1), a tank mix of glyphosate plus 2,4-D amine (0 - 7052 g·ae·ha^-1 + 0 - 6708), and 2,4-D choline/glyphosate DMA (0 - 13760 g·ae·ha^-1) were examined in the greenhouse for the control of two susceptible (GS) and two resistant to glyphosate (GR) Canada fleabane biotypes. The tank mix of 2,4-D amine plus glyphosate and 2,4-D choline/glyphosate DMA provided equivalent control of the GR Canada fleabane biotypes at 35 days after the application (DAA). The 2,4-D choline/glyphosate DMA treatment was more efficacious than the tank mix on the GS biotypes. Glyphosate (880 g·ae·ha^-1) provided 50% and 100% control of the resistant and susceptible biotypes, respectively. The 2,4-D choline/glyphosate DMA formulation and the tankmix of 2,4-D amine and glyphosate provided similar control of GR Canada fleabane.

Enlist, Glyphosate Resistant, Height, Injury, Seed Moisture, Yield

Ford, L. , Soltani, N. , Robinson, D. , Nurse, R. , McFadden, A. and Sikkema, P. (2014) Evaluation of 2,4-D Amine, Glyphosate, 2,4-D Amine plus Glyphosate DMA and 2,4-D Choline/Glyphosate DMA for Their Efficacy on Glyphosate Susceptible and Resistant Canada Fleabane Populations. Agricultural Sciences, 5, 1053-1060. doi: 10.4236/as.2014.511114.