Published Date: 2012-06-20 22:57:25
Subject: PRO/PL> Fusarium & undiagnosed blight, wheat - China
Archive Number: 20120620.1173738

FUSARIUM AND UNDIAGNOSED BLIGHT, WHEAT - CHINA
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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: Fri 15 Jun 2012
Source: Agrimoney [edited]
http://www.agrimoney.com/news/us-crop-scouts-deepen-cloud-over-china-wheat-hopes--4644.html


Grain scouts deepened the cloud over Chinese wheat by saying that 5m tonnes may have been lost to disease. "A severe blight may reduce China's winter wheat harvest," the US Grains Council said following a crop tour in the north of the country.

The comments come amid growing fears over the winter wheat crop, of which more than half has already been harvested, and which forms the great bulk of China's wheat output. The downgrade represents the latest in a rash of concerns over wheat harvests [internationally].

Separately, the China National Grains and Oil Information Centre, the official crop bureau, cut by 2.3m tonnes its forecast for the winter crop and the overall wheat harvest. "Output is lower than expected, while quality is also poor," the bureau said.

The main problem has been wet weather which has encouraged fungal diseases such as fusarium, or wheat scab.

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Communicated by:
ProMED-mail
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[Fusarium head blight (FHB; also called ear blight, scab) of small grain cereal crops (wheat, barley, rye, oats, maize) is caused by several fungal species originally classed into the genus _Fusarium_. FHB causes yield losses of up to 45 percent and reduces the grade of harvested grain. The pathogens are favoured by humid conditions and persist on infected crop residues. Spores are windblown or splashed onto the heads of cereal crops.

Depending on fungal strains involved and environmental factors during plant growth and grain storage, infection may also contaminate the grain with fungal toxins. The total crop may be lost because of toxin levels. Disease management includes timely fungicide applications and crop varieties with reduced susceptibility. However, new FHB strains with increased virulence are emerging.

It is not clear whether the fusarium mentioned in the last paragraph of the article above is also the "blight" referred to at the beginning of the report, or whether additional diseases are considered to be contributing to the problems. Several blight diseases (that is, symptoms of yellowing or bleaching) due to fungi and other pathogens can affect wheat, and the wet conditions described above would favour many of them.

Maps
China:
http://www.chinapage.com/map/map.html and
http://healthmap.org/r/1zaU
Provinces of China:
http://www.sacu.org/provmap.html

Pictures
Fusarium head blight (FHB) on wheat:
http://c.photoshelter.com/img-get/I0000urHINoyGOUw/s
Photo galleries of pathogen symptoms on wheat via:
http://wheatdoctor.cimmyt.org/en/image-galleries,
http://www.daff.qld.gov.au/26_7454.htm, and
http://www.ipmimages.org/browse/Areasubs.cfm?area=128

Links
Information on fusarium head blight of cereals:
http://bit.ly/LfuDNu,
http://www.agriculture.gov.sk.ca/Default.aspx?DN=24a3bb18-a096-4bcd-889c-b1e2c94a03e9,
http://smallgrains.psu.edu/pdf/FusariumHeadBlight.pdf, and
http://www.grainscanada.gc.ca/str-rst/fusarium/fhbwc-foc-eng.htm (with pictures)
FHB disease and toxin information:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex92
_F. graminearum_ current species complex and FHB information:
http://www.ars.usda.gov/Main/docs.htm?docid=9821
Taxonomy of fungal pathogens via:
http://www.indexfungorum.org/Names/Names.asp
Information on selected wheat diseases via:
http://wheatdoctor.cimmyt.org/en/pests-a-diseases/list,
http://cropwatch.unl.edu/web/wheat/disease, and
http://www.daff.qld.gov.au/26_3537.htm
List of major diseases and pathogens of wheat:
http://www.apsnet.org/publications/commonnames/Pages/Wheat.aspx. - Mod.DHA]

See Also

2010
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Fusarium head blight, cereals - UK: re-emergence 20100726.2497
Blue dwarf disease, wheat - China: new phytoplasma 20100716.2375
Fusarium head blight & stagonospora, wheat - USA: (OH) 20100708.2277
Fungal diseases, maize, wheat - USA 20100331.1017
2009
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Fusarium head blight, wheat - Canada: new strain 20091210.4211
Fusarium head blight, wheat - Uruguay 20091127.4066
Fusarium species, maize - Switzerland 20090911.3202
Fusarium head blight, oats - Canada: screening 20090621.2280
Fusarium head blight, wheat - USA 20090605.2078
Fungal diseases, cereal crops - China, Ireland 20090528.1983
Stripe rust, wheat - China 20090208.0579
2008
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Wheat stripe rust, oilseed rape sclerotinia - China 20080408.1297
Sharp eyespot, wheat - China 20080325.1119
2007
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Wheat stripe rust, wheat - China 20070413.1230
2004
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Wheat stripe rust - China 20040429.1191
1999
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Wheat mosaic virus, new - China (02) 19991114.2026
Wheat mosaic virus, new - China 19990115.0056
and additional items on fusarium head blight in the archives
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