Wheat yellow rust
Encyclopedia
Yellow rust, also known as stripe rust, is one of the three wheat
rust
diseases principally found in wheat grown in cooler environments. Such locations are generally associated with northern latitudes or cooler seasons.
-type disease was done by Eriksson and Henning in 1986. They named it Puccinia glumarum. At present, Puccinia striiformis is the name used by Hylander et al. (1953).
s. Primary hosts of yellow rust are Triticum aestivum (bread wheat), Triticum turgidum (durum
wheat), triticale
, and a few Hordeum vulgare (barley
) cultivars; the secondary host is still unknown.
The disease usually occurs early in the growth season, when temperature ranges between 2 and 15°C; but it may occur to a maximum of 23°C. High humidity and rainfall are favorable conditions for increasing the infection on both leaf blade and leaf sheath, even on spikes when in epidemic form. Symptoms are stunted and weakened plants, shriveled grains, fewer spikes, loss in number of grains per spike and grain weight. Losses can be 50%, but in severe situation 100% is vulnerable. In countries where wheat is grown in winters or at high elevations, yellow rust is a common threat, but not more significant than wheat leaf rust
and stem rust
, which are continuous threats in all wheat-growing countries.
Wheat
Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...
rust
Rust
Rust is a general term for a series of iron oxides. In colloquial usage, the term is applied to red oxides, formed by the reaction of iron and oxygen in the presence of water or air moisture...
diseases principally found in wheat grown in cooler environments. Such locations are generally associated with northern latitudes or cooler seasons.
History
This disease was first discovered by Gadd in 1977, but proper identification as another rustRust
Rust is a general term for a series of iron oxides. In colloquial usage, the term is applied to red oxides, formed by the reaction of iron and oxygen in the presence of water or air moisture...
-type disease was done by Eriksson and Henning in 1986. They named it Puccinia glumarum. At present, Puccinia striiformis is the name used by Hylander et al. (1953).
Symptoms
"Yellow rust" takes its name from the appearance of yellow-colored stripes produced parallel along the venations of each leaf blade. These yellow stripes are actually characteristic of uredinia that produce yellow colored urediniosporeUrediniospore
Urediniospores are the thinner-walled spores of some fungi: , from which the basidium arises.-Morphology:*Urediniospores are usually consist of two dikaryote nuclei within one constricted cell resembling the number 8 without a septation...
s. Primary hosts of yellow rust are Triticum aestivum (bread wheat), Triticum turgidum (durum
Durum
Durum wheat or macaroni wheat is the only tetraploid species of wheat of commercial importance that is widely cultivated today...
wheat), triticale
Triticale
Triticale is a hybrid of wheat and rye first bred in laboratories during the late 19th century. The grain was originally bred in Scotland and Sweden. Commercially available triticale is almost always a second generation hybrid, i.e., a cross between two kinds of primary triticales...
, and a few Hordeum vulgare (barley
Barley
Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods...
) cultivars; the secondary host is still unknown.
The disease usually occurs early in the growth season, when temperature ranges between 2 and 15°C; but it may occur to a maximum of 23°C. High humidity and rainfall are favorable conditions for increasing the infection on both leaf blade and leaf sheath, even on spikes when in epidemic form. Symptoms are stunted and weakened plants, shriveled grains, fewer spikes, loss in number of grains per spike and grain weight. Losses can be 50%, but in severe situation 100% is vulnerable. In countries where wheat is grown in winters or at high elevations, yellow rust is a common threat, but not more significant than wheat leaf rust
Wheat leaf rust
Wheat leaf rust, is fungal disease that effects wheat, barley and rye stems, leaves and grains. In temperate zones it is destructive on winter wheat because the pathogen overwinters. Infections can lead up to 20% yield loss - exacerbated by dying leaves which fertilize the fungus. The pathogen is...
and stem rust
Stem rust
The stem, black or cereal rusts are caused by the fungus Puccinia graminis and are a significant disease affecting cereal crops. An epidemic of stem rust on wheat caused by race Ug99 is currently spreading across Africa, Asia and most recently into Middle East and is causing major concern due to...
, which are continuous threats in all wheat-growing countries.