Tilletia controversa
Encyclopedia
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 wheat
s. It stunts the growth of the plants and leaves smut balls in the grain heads. When the grain is milled
the smut balls emit a fishy odor that lowers the quality of the flour
.
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
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
n exports.
Basidiomycota
Basidiomycota is one of two large phyla that, together with the Ascomycota, comprise the subkingdom Dikarya within the Kingdom Fungi...
known to cause the smut
Smut (fungus)
The smuts are multicellular fungi, that are 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 and can cause plant disease...
disease TCK smut in soft white and hard red winter wheat
Winter wheat
Winter wheat is a type of wheat that is planted from September to December in the Northern Hemisphere. Winter wheat sprouts before freezing occurs, then becomes dormant until the soil warms in the spring. Winter wheat needs a few weeks of cold before being able to flower, however persistent snow...
s. It stunts the growth of the plants and leaves smut balls in the grain heads. When the grain is milled
Mill (grinding)
A grinding mill is a unit operation designed to break a solid material into smaller pieces. There are many different types of grinding mills and many types of materials processed in them. Historically mills were powered by hand , working animal , wind or water...
the smut balls emit a fishy odor that lowers the quality of the flour
Wheat flour
Wheat flour is a powder made from the grinding of wheat used for human consumption. More wheat flour is produced than any other flour. Wheat varieties are called "clean," "white," or "brown" if they have high gluten content, and they are called "soft" or "weak" flour if gluten content is low...
.
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
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
applied a zero tolerance
Zero tolerance (trade)
In food safety policy, a zero tolerance standard generally means that if a potentially dangerous substance is present in or on a product, that product will be considered adulterated and unfit for human consumption...
on the presence of TCK spores, resulting in a ban from 1974 to 1999 on shipments from the Pacific Northwest
Pacific Northwest
The Pacific Northwest is a region in northwestern North America, bounded by the Pacific Ocean to the west and, loosely, by the Rocky Mountains on the east. Definitions of the region vary and there is no commonly agreed upon boundary, even among Pacific Northwesterners. A common concept of the...
. 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
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
n exports.