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[1] Wheat stem rust, strain Ug99 - Iran: 1st report, alert
[2] Wheat stem rust, strain Ug99 - multistate: alert

[1] Wheat stem rust, strain Ug99 - Iran: 1st report, alert
Date: Wed 5 Mar 2008
Source: United Nations Food and Agricultural Organisation (FAO) Newsroom [edited] <http://www.fao.org/newsroom/en/news/2008/1000805/index.html>

Wheat killer detected in Iran - dangerous fungus on the move from East Africa to the Middle East

A new and virulent wheat fungus, previously found in East Africa and Yemen, has moved to major wheat-growing areas in Iran, FAO reported today [5 Mar 2008]. The fungus is capable of wreaking havoc to wheat production by destroying entire fields. Countries east of Iran, like Afghanistan, India, Pakistan, Turkmenistan, Uzbekistan, and
Kazakhstan, all major wheat producers, are most threatened by the fungus and should be on high alert, FAO said.

It is estimated that as much as 80 percent of all wheat varieties planted in Asia and Africa are susceptible to wheat stem rust (_Puccinia graminis_). The spores of wheat rust are mostly carried by wind over long distances and across continents. "The detection of the wheat rust fungus [strain Ug99] in Iran is very worrisome," said
Shivaji Pandey, director of FAO's Plant Production and Protection Division. "The fungus is spreading rapidly and could seriously lower wheat production in countries at direct risk. Affected countries and the international community have to ensure that the spread of the disease gets under control in order to reduce the risk to countries that are already hit by high food prices."

The government of the Islamic Republic of Iran has informed FAO that the fungus has been detected in some localities in Broujerd and Hamedan in western Iran. Laboratory tests have confirmed the presence of the fungus. Iran said it will enhance its research capacity to face the new infection and develop new wheat varieties resistant to the disease.

The wheat fungus [strain] first emerged in Uganda in 1999 and is therefore called Ug99. The wind-borne transboundary pest subsequently spread to Kenya and Ethiopia. In 2007, an FAO mission confirmed for the 1st time that Ug99 has affected wheat fields in Yemen. The Ug99 strain found in Yemen was already more virulent than the one found in East Africa. Ethiopia and Kenya had serious wheat rust epidemics in 2007 with considerable yield losses.

Disease surveillance and wheat breeding is already underway to monitor the fungus and to develop Ug99 resistant varieties. However, more efforts are required to develop long term durable resistant varieties that can be made available to farmers in affected countries and countries at risk. FAO urged countries to increase disease
surveillance and intensify efforts to control the disease.

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[2] Wheat stem rust, strain Ug99 - multistate: alert
Date: Wed 5 Mar 2008
Source: The Dawn [edited]
<http://www.dawn.com/2008/03/06/top18.htm>

FAO warning over virulent wheat fungus

The Food and Agriculture Organisation (FAO) of the United Nations has asked the authorities of Pakistan and 5 other wheat-producing countries, located east of Iran, to be on high alert, following a report that a new and virulent wheat fungus has moved to major wheat-growing areas in Iran. According to FAO, countries in the
predicted, immediate pathway grow more than 65 million hectares (approx. 161 million acres) of wheat, accounting for 25 percent of the global wheat harvest.

Quoting M. E. Tasneem, Chairman of the Pakistan Agriculture Research Council, the FAO said: "If we don't control this stem rust threat, it will have a major impact on food security, especially since global wheat stocks are at a historic low".

"If we fail to contain Ug99 it could bring calamity to tens of millions of farmers and hundreds of millions of consumers," says Nobel Laureate Borlaug. "We know what to do and how to do it. All we need are the financial resources, scientific cooperation, and political will to contain this threat to world food security." The Global Rust Initiative (GRI) will support countries in developing resistant varieties, producing clean quality seeds, upgrading
national plant protection and plant breeding services, and developing contingency plans. The BGRI was founded by Norman Borlaug (Cornell University, USA), the International Centre for Agricultural Research in Dry Areas [ICARDA, Syria], the International Maize and Wheat Improvement Centre [CIMMYT, Mexico], and the FAO.

[Byline: Amin Ahmed]

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[Wheat stem rust is caused by the fungus _Puccinia graminis_ f. sp. _tritici_. It occurs worldwide throughout wheat producing areas. Symptoms are dark orange pustules on the stems and also on the leaves. Stems can be completely girdled by the pustules damaging the conducting tissue and preventing grain fill. Yield losses of up to 70 percent are reported, but some fields are totally destroyed. If stem rust arrives early in the growing cycle, losses are higher. The fungus is spread by wind and with infected straw.

New pathogen races are emerging with increased virulence against genes previously used for resistance breeding. Considered most dangerous at present is strain Ug99. It can infect and cause disease in many commonly grown stem rust "resistant" wheat lines. In much of the world, resistance to stem rust in wheat is based at least in part
on the gene Sr31. High levels of stem rust infection were observed in Uganda on wheat lines containing the Sr31, Lr26, and Yr9 genes for rust resistance, and Ug99 was identified as a new strain with virulence to Sr31.

Recurring epidemics in Kenya and then Ethiopia followed, and Ug99 has recently spread to Yemen. It may also be present in Pakistan, Sudan, and Tanzania and appears to be moving on prevailing winds. Furthermore, an even more virulent variant of Ug99 able to overcome additional resistance genes has recently emerged in Kenya. This
increases the threat posed by Ug99 to global wheat production further. International screening programmes for germplasm with resistance to the new strains are being set up under the GRI.

Maps
Iran:
<http://www.lib.utexas.edu/maps/middle_east_and_asia/iran_pol01.jpg>  and
<http://healthmap.org/promed?v=32.7,54.2,5>
Middle East, including Ug99 alert area:
<http://worldatlas.com/webimage/countrys/me.htm>
Africa:
<http://worldatlas.com/webimage/countrys/africa/maps/africa.htm>

Pictures of stem rust on wheat:
<http://scarab.msu.montana.edu/Disease/DiseaseGuidewebpics/Petewebpics41-50/Img0042.jpg>, 

<http://www.cimmyt.org/english/wps/news/2005/sept/images/stem2.jpg>  and
<http://www.gov.mb.ca/agriculture/crops/diseases/images/fac15s01.jpg>

Links
Information on wheat stem rust:
<http://www.ars.usda.gov/Main/docs.htm?docid=9910>
Information on Ug99:
<http://www.agbioworld.org/newsletter_wm/index.php?caseid=archive&newsid=2686>
and
<http://www.pestalert.org/viewNewsAlert.cfm?naid=36>
Ug99 distribution and potential global impact:
<http://www.cimmyt.cgiar.org/gis/pdf/UG99postH.pdf>
Ug99 and stem rust resistance genes used in wheat breeding:
<http://www.ars.usda.gov/Main/docs.htm?docid=14649>
_P. graminis_ f.sp. _tritici_ taxonomy:
<http://www.indexfungorum.org/Names/NamesRecord.asp?RecordID=455607>
Global Rust Initiative:
<http://www.globalrust.org/>
CIMMYT:
<http://www.cimmyt.org/>
ICARDA:
<http://www.icarda.org/>.  - Mod.DHA]