Mississippi State University
Reynolds, Daniel B.
Dodds, Darrin M.
Krutz, Larry J.
Spencer, Gene D.
Date of Degree
Graduate Thesis - Open Access
Master of Science (M.S.)
College of Agriculture and Life Sciences
Department of Plant and Soil Sciences
This study was conducted to determine whether soybean productivity is affected by multiple, sublethal herbicide exposures. The effects of dicamba and 2,4-D on soybean (Glycine max) productivity was investigated at 17 site-years. Relative to a single exposure of dicamba at R1, an additional exposure at either V3 or R3 reduced yield up to 23%. Three or more applications did not further decrease yields relative to an R1&R3 exposure. For 2,4-D, a single application to V3, R1, R3, or R5 soybean did not affect grain yield. However, two exposures of 2,4-D occurring from V3 through R3 reduced yield 5 to 7%. Three or more applications of 2,4-D had no effect on yield relative to exposing soybean to 2,4-D twice between V3 and R3. Exposing soybean to multiple, sublethal rates of auxin herbicides can reduce yield relative to a single exposure and may be most deleterious from flowering to initial pod set.
Oakley, Graham Robert, "Soybean (Glycine max) response to multiple, sublethal exposures of 2,4-D and dicamba from vegetative through reproductive growth" (2021). Theses and Dissertations. 5376.