Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School



Wild oat (Avena fatua) is a major weed problem in small grains grown in the Central Plains area. Preemergent herbicides have been development which control wild oat. Diallate (S-(2,3-dichlorallyl) diisoprophylthiocarbamate) and triallate (S- (2,3,3-trichloroallyll) diisoprophylthiocarbamate) are preemergent herbicides which give good short-term control of wild oat. However, late germinating wild oat may emerge to reeducate yield. Barban (4-chloro-2-butynyl m-chlorocarbanilate) is a postemergent herbicide, but is effective only at the early growth stages of wheat. A late postemergent herbicide is needed to allow more wild oat to germinate for better full-season control. A late postemergence herbicide would also aid in preventing the production of wild oat seeds should a heavy infestation develop after the crop has emerged. The objectives of this thesis were to determine the response of sixteen wheat varieties to diffenzoquat and to determine the stage of growth that wheat can safely by treated diffenzoquat.

Library of Congress Subject Headings

Wheat -- Diseases and pests

Herbicides -- Toxicology

Wild oat



Number of Pages



South Dakota State University