Theses and Dissertations

Issuing Body

Mississippi State University


Dodds, Darrin M.

Committee Member

Krutz, L. Jason

Committee Member

Spencer, Gene David

Committee Member

Rushing, J. Brett

Date of Degree


Document Type

Graduate Thesis - Open Access


Plant and Soil Sciences

Degree Name

Master of Science (M.S.)


College of Agriculture and Life Sciences


Department of Plant and Soil Sciences


Italian ryegrass is a problematic weed in Mississippi corn production due to the development and proliferation of glyphosate resistance. Studies were conducted to assess Italian ryegrass control prior to planting using herbicides. Effects of fall and spring applied burndown herbicide applications for Italian ryegrass control and subsequent corn grain yield were investigated at the R.R. Foil PSRC in Starkville, MS, at the Coastal Plain Experiment Station in Newton, MS, and the Black Belt Experiment Station in Brooksville, MS on soil textures ranging from sandy loam to silt clay loam. A fall preemergence (PRE) application of S-metolachlor + metribuzin followed by paraquat in the spring provided 99% Italian ryegrass control 28 days after paraquat application. Four spring burndown treatments provided Italian ryegrass control similar to that observed following application of the fall PRE application followed by paraquat in the spring. Applications clethodim + glufosinate + paraquat + dimethenamid-P; clethodim + glufosinate + paraquat + S-metolachlor; clethodim + paraquat + dimethenamid-P; and clethodim + oxyfluorfen + paraquat + S-metolachlor resulted in similar levels of Italian ryegrass control at 96%, 98%, 94%, and 99%, respectively. Corn yield following the fall PRE followed by spring paraquat application was 10,687 kg ha-1. Corn yield following clethodim + paraquat + dimethenamid-P as well as clethodim + oxyfluorfen + paraquat + S-metolachlor applied in the spring resulted in similar corn grain yield to that following the fall PRE followed by spring paraquat application at 9,649 kg ha-1 and 9,567 kg ha-1, respectively. Spring burndown herbicide treatments could be used to control Italian ryegrass while producing similar corn yield to the standard fall herbicide followed by paraquat application in the spring.

Included in

Agriculture Commons