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[1] Kentucky
[2] Illinois and other wheat states

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[1] Kentucky
Date: Mon 1 Jun 2009
Source: Southeast Farm Press [edited]
<http://southeastfarmpress.com/grains/fusarium-wheat-0601/>

Fusarium widespread in Kentucky wheat crop

During the past week [beginning 25 May 2009], the disease fusarium head blight [FHB] or "head scab" has appeared at significant levels in many wheat fields across Kentucky. Depending on the severity, it could pose potential problems for many agricultural sectors, said Don Hershman, University of Kentucky. "There could be more disease development over the next week or so," he said.

FHB attacks wheat around flowering stage, which is where most of the state's wheat was when wet weather hit end of April [2009] through the first week in May. The wet, cloudy conditions likely favored multiple infection periods, which has resulted in an extended window for disease development.

FHB is present in Kentucky wheat every year to some extent, but some years are more severe. The last statewide epidemic was in 1991, but there have been several lesser epidemics since. This year [2009] could rival what was seen 18 years ago. "FHB is not quite at 1991 levels, but it's definitely the worst it's been since," Hershman said. Fungicides only have about a 50 percent FHB suppression rate, so some treated fields still have a lot of disease. No [suitable] fungicides were available in 1991.

FHB can cause lower yields and seed weights, but the larger concern is that the fungus also produces the mycotoxin deoxynivalenol (DON).
Fields with FHB almost always have DON, too. Grain products with DON levels greater than accepted norms are not suitable for human or animal consumption.

Wheat producers also are combating stagonospora leaf and glume blotch, and leaf rust, among other diseases. "Their severity is notable in many fields for the same reason we are seeing a lot of FHB
-- a wet May," Hershman said. "Even treated fields are showing increased disease activity as fungicides applied in early May [2009] begin to wear off."

[Byline: Katie Pratt, University of Kentucky]

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[2] Illinois and other wheat states
Date: Tue 2 Jun 2009
Source: FXstreet/Dow Jones Newswires [edited]
<http://www.fxstreet.com/news/forex-news/article.aspx?StoryId=287ce59f-a156-4216-8ad1-dfdfb77917ba>

US cash grain outlook

In USDA's [United States Department of Agriculture] report, problems with the fungal disease fusarium head blight, or head scab, were reported again in soft red winter [SRW] wheat states because of wet weather during the flowering stage. The soggy state of Illinois saw its SRW wheat rating drop 11 percentage points from last week [week of 25 May 2009] because of head scab.

[Byline: Debbie Carlson]

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[Fusarium head blight (FHB; also called scab) on wheat is caused by several fungal species originally classed into the genus _Fusarium_, accounting for the common name of this disease. Current names of the fungi are _Gibberella zeae_, _Fusarium poae_, _Monographella nivalis_ var. _nivalis_, and _Microdochium majus_. FHB causes yield losses of up to 45 percent and reduces the grade of harvested grain. It may also contaminate the grain with fungal toxins, for example DON (also called vomitoxin), which can affect stock and may lead to reduced feed consumption or feed refusal. The total crop may be lost if grain is rejected because of toxin levels. Disease management includes timely fungicide applications and crop varieties with reduced susceptibility.

Stagonospora glume blotch is caused by 2 fungi now classified as _Phaeosphaeria avenaria_ f.sp. _triticae_ and _Phaeosphaeria nodorum_. Leaf rust (or brown rust) of wheat is caused by the fungus _Puccinia recondita_. For more information on all diseases please see links below.

Maps of USA:
<http://www.mapsofworld.com/usa/usa-state-and-capital-map.html>,
<http://healthmap.org/r/00e0>,  and
<http://healthmap.org/r/00e1>

Pictures
Fusarium head blight symptoms, wheat:
<http://www.nwroc.umn.edu/Cropping_Issues/2005/issue6/FHB_examples.jpg>  and <http://plantsci.sdstate.edu/planthealth/other_images/scab.jpg>
Wheat glume blotch:
<http://www.oznet.ksu.edu/path-ext/factsheets/wheat/Wheatimages/glume%20blotch2.jpg>
Leaf rust on wheat:
<http://www.hgca.com/hgca/wde/IMAGES/brown%20rust1.JPG>

Links
FHB information:
<http://www.apsnet.org/education/feature/FHB/> and <http://smallgrains.psu.edu/pdf/FusariumHeadBlight.pdf>
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>
Information on wheat glume blotch:
<http://www.oznet.ksu.edu/path-ext/factSheets/Wheat/Wheat%20Glume%20Blotch%20Complex.asp>
Information on wheat leaf rust:
<http://plant-disease.ippc.orst.edu/disease.cfm?RecordID=1138>  and
<http://www.oznet.ksu.edu/path-ext/factSheets/Wheat/Wheat%20Leaf%20Rust.asp>
Taxonomy of all fungal pathogens via:
<http://www.indexfungorum.org/Names/Names.asp>
List of wheat diseases and pathogens:
<http://www.apsnet.org/online/common/names/wheat.asp>.  - Mod.DHA]