Smut, Sphace!otheca, Sporisorium, big bluestem
Sphacelotheca occidentalis causes kernel smut disease of Andropogon gerardii, a prairie grass. The smut fungus is systemic, perennial, causes severe stunting, and sporulates in florets. Spores develop in gall-like sari composed of grass and fungal cells. Spores initiate in a meristematic area near the base of the sorus, and progressively more mature spores are found toward the sorus rip. The cylindrical sari have a central columella of host vascular tissue permeated by hyphae, sporogenous hyphae and developing teliospores that surround the columella, and a peridium of host and fungal cells. Sporogenous hyphae ramify in a gelatinous matrix that disappears as the teliospores enlarge. Teliospores become ornamented as they enlarge; mature teliospores bear two sizes of spines. Sorus and teliospore characters suggest that S. occidentalolis belongs in Sporisorium. Kernel smut has been collected on native and planted bluestem prairies in Iowa since 1978 when it was first reported in the state. Colonies of diseased bluestem are especially prevalent in several native prairies of northwest Iowa.
Journal of the Iowa Academy of Science
© Copyright 1991 by the Iowa Academy of Science, Inc.
Snetselaar, Karen M. and Tiffany, Lois H.
"A Study of Sphacelotheca occidentalis, Cause of Kernel Smut of Big Bluestem,"
Journal of the Iowa Academy of Science: JIAS, 98(3), 142-152.
Available at: https://scholarworks.uni.edu/jias/vol98/iss3/9