A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the International Society for Infectious Diseases <http://www.isid.org>

Date: April 2009
News-Leader (Missouri) [edited]
<http://www.news-leader.com/article/20090424/BREAKING01/90424023/>

Agriculture department warns growers about California rice seed

High demand for medium grain rice might prompt some Missouri rice growers to try a crop, but the Missouri Department of Agriculture is warning farmers not to purchase medium grain rice seed from California.

Missouri currently has a quarantine on California rice seed and on California seed from other states because of the threat of bakanae infection.

Bakanae is a fungus common to other countries but first introduced to the USA in 1999. Missouri currently has no reported cases of bakanae disease in rice seeds.

Once established, bakanae cannot be eliminated from a rice-growing area, according to the department.

--
Communicated by:
ProMED-mail
<promed@promedmail.org>

[Bakanae disease of rice (also called foot rot in some Asian countries) is caused by the fungus _Gibberella fujikuroi_ and can cause significant crop losses of up to 20 percent. The fungus also affects other crops, including barley, maize, sorghum, sugarcane, tomato, banana, and cowpea. Symptoms on rice include abnormal growth patterns, death of seedlings, reduced tillering, and partially filled or empty seed heads.

The fungus infects plants through roots or crowns and later becomes systemic. Seeds are usually infected during the flowering stage and the disease is primarily seed-borne. The fungus survives under adverse conditions in infected seeds and diseased plant parts.
Disease management is difficult and includes use of certified clean seeds and fungicides, however rapid development of pathogen resistance has been observed.

Similar warnings of possible bakanae incursions with Californian rice seed have been issued for Arkansas and other states earlier (see ProMED-mail posts below).

Maps
USA:
<http://www.mapsofworld.com/usa/usa-road-map-enlarge-view.html> and <http://healthmap.org/r/00at>
US states:
<http://www.census.gov/geo/www/us_regdiv.pdf>

Pictures of bakanae symptoms and fungal spores:
<http://plantpro.doae.go.th/diseasegroup/rice/bakanae/bakanae.jpg>

Links
Bakanae disease fact sheet (with pictures):
<http://www.knowledgebank.irri.org/RiceDoctor/Fact_Sheets/Diseases/Bakanae.htm>
_G. fujikuroi_ taxonomy:
<http://www.indexfungorum.org/Names/NamesRecord.asp?RecordID=265414>.
- Mod.DHA]

[see also in the archive:
Rice diseases - USA (02): quarantine 20090317.1079 Rice diseases - USA: quarantine 20090313.1029
2008
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Foot rot & false smut, rice - India 20080929.3080]