Karnal bunt: essential data

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Karnal Bunt :essential data
Disease Name, Other Names, Crops Affected Causative Agent, Synonyms, Description of the Agent Symptoms, Prevention and Treatment Other Comments
Disease name	Karnal bunt
Other Names	Covered smut Partial bunt Wheat cover smut
Causative Agent	Tilletia indica
Synonyms	Neovossia indica
Crops Affected	All forms of wheat and the wheat/rye hybrid Triticale.
Description of the Agent	The fungus is a member of the Basidiomycetes, the club fungi, and within them it is a member of the smuts (Ustilaginaceae). It has a complex life cycle with several different stages producing spores. the most important is the robust terminal spore or teliospore. The teliospore is hardy and can survive in soil for several years. Spores can also be carried significant distances by the wind and burning of field stubble can send the spores high into the air where they can be carried great distances. The teliospores can germinate under a wide range of temperatures. However, they are only capable of infecting the plant during a very narrow stage during the development of the plant: the second half of development of the ear.
Symptoms	Bunt infects the ears of the plant and replace the kernels with spores. The wheat develops a fishy odor.The effects on kernel shape and color are slight and can be missed during field inspections, although the ear may show some abnormalities in development. The infected corn is unpalatable to humans, but it is not toxic and has no adverse effects on humans or livestock.
Prevention and Treatment	Treatment is relatively difficult. The teliospores can be wind-borne so typical measures, such as using disease-free seed, does not help. Resistant varieties of wheat may be used and some systemic fungicides, including propiconazole, are effective. Fields infected with the bunt should be quarantined for up to five years. Other crops, such as maize, soy, or alfalfa may be grown, but equipment must be thoroughly sterilized or kept separate from that used in other wheat fields.
Other Comments	Karnal bunt is an economic weapon. It does not destroy the plant or have a significant impact on yield. The effects are first seen after harvest. The crop becomes unusable if the content of smutted corn is greater than 3%. It may be useful for feed but cannot be sold for the more profitable bread, pasta, or cereal markets. Bunts have an indirect effect on the farm economy. A dust of spores generated by harvesting with a combined harvester can be explosive and can cause expensive damage to the machine. The disease is very limited in distribution. It is only found in India, Pakistan, mexico, and the southwestern US. It takes its name from the town of Karnal, which is the Punjab, where it was first identified as a new disease. Iraq is reported to have studied the possible use of karnal bunt as a biological weapons. There are approximately 200 species of Tilletia, many of which are plant pathogens.

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