Issuing Body

Mississippi State University


Ferguson, Jason Connor

Committee Member

Brown-Johnson, Ashli

Committee Member

Reynolds, Daniel B.

Committee Member

Tseng, Te-Ming (Paul)

Date of Degree


Original embargo terms

Visible to MSU only for 1 Year||12/15/2020

Document Type

Graduate Thesis - Open Access


Plant and Soil Sciences

Degree Name

Master of Science


College of Agriculture and Life Sciences


Department of Plant and Soil Sciences


Field studies were conducted to test three application methods for applying antagonistic herbicide combinations: 1) tank mix (TMX), 2) mix-in-line (MIL), and 3) separate boom (SPB). Sethoxydim applied with bentazon, glyphosate applied with dicamba or 2,4-D, and clethodim applied with dicamba or 2,4-D had higher efficacy when applied using the SPB method. Antagonism of all the herbicide combinations above was observed when applied using the TMX and MIL methods. In some cases, antagonism was avoided when using the SPB method. Three application methods tested in greenhouse studies were 1) TMX, 2) synthetic auxin applied first (AAF), and 3) synthetic auxin applied second (AAS). The AAS application method resulted in higher weed control than the TMX and AAF methods. Analysis done through liquid chromatography mass spectrometry supported the greenhouse results with higher rates of glyphosate detected with the AAS method.



2,4-D||Dicamba||Herbicide antagonism||Clethodim||Glyphosate||Sethoxydim||Bentazon||Tank mix||Sequential applications||Mix-in-line||Separate boom