Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Plant Science

First Advisor

David Walgenbach


The purpose of this study was to evaluate cultural methods for sunflower seed weevil control. Procedures examined included the influences of tillage methods, crop rotation, date of planting, hybrid maturity, and degree-day units in emerging seed weevil populations. Tillage practices done as both fall and spring treatments including discing, chisel plowing, nobel blading, and moldboard plowing were examined for their effect on larval position in the soil, time of adult weevil emergence, and the number of adults emerging from the soil. Crop rotations were investigated for possible influence on weevil mortality and time of adult emergence. Sunflower planting date and hybrid maturity were compared to sees weevil ovipositional patterns. Degree-day accumulations were utilized for potential predictive values in assessing adult weevil emergence.

Library of Congress Subject Headings

Sunflowers -- Diseases and pests
Sunflowers -- Diseases and pests -- South Dakota
Tillage -- South Dakota



Number of Pages



South Dakota State University