Disease Note Report of Buffalograss Bunt (Tilletia buchloëana) in Oklahoma. D. R. Huff, Department of Environmental Horticulture, University of California, Davis 95616. D. Zagory, and L. Wu. Department of Environmental Horticulture, University of California, Davis 95616. Plant Dis. 71:651. Accepted for publication 3 April 1987. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0651D. Among 25 male and 26 female buffalograss (Buchloe dactyloides
(Nutt.) Engelm.) plants collected vegetatively in Kingfisher County,
Oklahoma, in July 1986, one male plant was found to be infected with a
covered smut. This plant developed floral parts with pistillate structures
containing an ovary, ovule, and stigmas. The ovaries developed into
sori filled with teliospores that were light chocolate brown to pale
yellow and 18-20 µm in diameter, including the sheath. Sheath
thickness was 2.5-5.0 µm, with lighter colored spores tending to have
thicker sheaths. Tubercles were 1.0--2.5 µm long. Sori emitted a foul,
fishy odor. On the basis of these characteristics, we have identified the
fungus as Tilletia buchloeana Kell. & Swing. T. buchloeana has been
observed only on male buffalograss plants and is the only species of
Tilletia known to induce hermaphroditism in its host. T. buchloeana
has been reported to occur in Kansas, Nebraska, and Texas but has not
been previously reported to occur in Oklahoma (1), where
approximately 30% of U.S. buffalograss seed is produced. |