Date of Award:

5-1-1991

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Biology

Department name when degree awarded

Biology (Entomology)

Committee Chair(s)

Wilford J. Hanson

Committee

Wilford J. Hanson

Committee

Donald Davis

Committee

Jay B. Karren

Abstract

Studies were conducted to explore the relationship of common insect pests associated with the cultivar 'Hycrest' crested wheatgrass, Agropyron cristatum (L.) and A. desertorum (Fisher x Link). Insect population surveys were conducted on three farms during three summers to determine relative insect numbers. Thrips, Trigonotylus ruficornis, and Lygus hesperus were found to be the most abundant insect pests infesting Hycrest plants. A broad population peak was observed covering most of July through August for thrips, T. ruficornis, and L. hesperus. In addition to pest insects, the following beneficial insects were collected in significant numbers: Nabidae, Coccinellidae, Collops, Chrysopidae, and predatory thrips. Two series of studies were conducted to determine effects of L. hesperus populations, during a growing season, on moisture content and germination of Hycrest seed. Neither was found to be affected by L. hesperus.

Download

Share

COinS

Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .