Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Plant Pathology


Stalk rot is one of the major diseases of dent corn in the north central corn producing area of the United States. Besides Diplodia zeae (Schw.( Lev., and Gibberella zeae (Schw.) Petch. Other stalk rotting microorganisms are Fusarium moniliforne Sheldon, emend, Snyder and Hansen, causing Fusarium stalk rot; Scleretium bataticola Taub., causing charcoal rot; Erwinia dissolvens (Rosen) Birkh., causing bacterial stalk rot; Pythium butleri Subr., causing Pythium stalk rot; and Nigrosoora oryzae (Berk. and Br. ) Petch, causing Nigrospora stalk rot. Losses vary from year to year depending on weather, variety of corn and amount of inoculum present in or on the soil. Under favorable ecological conditions it is not uncommon to observe dying plants in the late stage of their development. During the past two decades conscious effort has been made by plant breeders and plant pathologists of the Corn Belt to incorporate stalk rot resistance in new developing hybrids. The same effort has been made by plant pathologists and corn breeders at the South Dakota Agricultural Experiment Station. The present study was part of latter effort and was concerned with determining (a) the reactions of inbred lines alone and in top cross combination with the single cross SD26 x B8 to stalk inoculations with D. zeae and G. zeae and (b) to compare the reactions of those plants to each of the two fungi. In addition, the results from these inoculations were also compared with those from sterile water inoculated plants. The inbred lines comprised 80 developed by the Plant Pathology Department of the South Dakota Agricultural Experiment Station and 68 developed or acquired from other sources by the Agronomy Department of that same station.

Library of Congress Subject Headings

Corn -- Diseases and pests
Gibberella zeae
Diplodia zeae


Includes bibliographical references



Number of Pages



South Dakota State University