''Tilletia controversa'' is a plant pathogen. It is a
fungus known to cause the
smut disease TCK smut in soft white and hard red
winter wheats. It stunts the growth of the plants and leaves
smut balls
The smuts are multicellular fungi characterized by their large numbers of teliospores. The smuts get their name from a Germanic word for dirt because of their dark, thick-walled, and dust-like teliospores. They are mostly Ustilaginomycetes (phylum ...
in the grain heads. When the grain is
milled the smut balls emit a fishy odor that lowers the quality of the
flour
Flour is a powder made by grinding raw grains, roots, beans, nuts, or seeds. Flours are used to make many different foods. Cereal flour, particularly wheat flour, is the main ingredient of bread, which is a staple food for many culture ...
.
TCK smut exists in the western and northwestern United States, but is not considered a major problem. The disease took on policy significance because
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
applied a
zero tolerance on the presence of TCK spores, resulting in a ban from 1974 to 1999 on shipments from the
Pacific Northwest. Until the summer of 1996, China accepted shipments of U.S. wheat from the
Gulf Coast, and negotiated price discounts with the shippers to cover the cost of decontamination if traces of TCK were found. Then in June 1996, China rejected all cargoes of U.S. wheat with traces of TCK. The November 1999
U.S.-China Agricultural Cooperation Agreement removes the ban and allows imports of U.S. wheat and other grains that meet a specific TCK tolerance level, thus improving the competitiveness of U.S. wheat with
Canadian and
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
n exports.
References
External links
Index FungorumUSDA ARS Fungal Database
*
Fungal plant pathogens and diseases
Wheat diseases
Ustilaginomycotina
Fungi described in 1874
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