Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School



In the summer of 1921, Professor E.J. Petry noted an unusually severe uredinial infection on a small patch of Spartina cynosuroides (L) Roth, along the Chicage and northwestern right-of-way near Brookings, South Dakota. Along with this occurred an aecidial infection on Steironema ciliatum (L) Raf. Since the Steironema was small and mingled with the Spartina in places, a connection between the telial stage of the latter with the aecidial attack was trongly suspected. The infection occurred only on the lower leaves of the Steironema and this heightened the probabili8ty of infection from the teliospore sporadia of the Spartina which lay in masses around the bases of the Steironema plants. As a result of these observations, plans were made to have the writer study these plants to determine if they were the alternate hosts of the rust. However, late in the fall of 1921, the writer, in reviewing the rusts which attack Spartina cynosuroides, found that Dicaeoma Distichlidis (Ellis and Ev.) Kuntze on Spartina had already been connected (15) with the aecidial stage on Steironema ciliatum. Thus part of the problem of the biology of this rust was already solved. By correspondence with Dr. J. C. Arthur it was learned that the cytology of this disease-producing organism had never been worked out. We then determined to investigate the cytology of the aecidial stage and to see whether or not the phenomena of so-called fertilization found by other workers, could be demonstrated in the case of Dicaeoma Distichlidis.

Library of Congress Subject Headings

Rust fungi


Includes bibliographical references (page 16-17)



Number of Pages



South Dakota State College


No Copyright - Non-Commercial Use Only