A
ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases <http://www.isid.org>
[1] Missouri
Date: Tue 1 Jul 2008
Source: Missouri Ruralist, MU Extension Cooperative Media Group
report [edited] <http://missouriruralist.com/index.aspx?ascxid=fpStory&fpsid=34580&fpstid=2>
Wheat scab is widespread
Heavy spring rainfall in Missouri has created ideal conditions
for wheat scab. The fungal disease is widespread throughout the
wheat growing regions of the state and threatens to lower yields
and reduce seed quality. "It's been a long time since we've had
a statewide problem with scab," says Laura Sweets, University of
Missouri (MU) Commercial Agriculture Extension plant
pathologist. "You really need wet conditions as the crop is
flowering and right after flowering for scab to take off."
Wheat scab, also known as fusarium head blight, affects wheat
heads and kernels. Damaged kernels can result in major declines
in yield and quality. Signs of scab include shrunken or
discolored kernels with a pink or chalky tinge. Some may appear
as "tombstone kernels,"
which are white, softer than normal and have an odd texture.
Farmers with discolored, stunted kernels may be docked on wheat
at the elevator. The fungus can produce mycotoxins that may
affect livestock, lowering feed intake and reducing weight gain.
It's too late in the season to treat scab with fungicides, Sweet
says, but farmers can try to reduce the number of tainted grains
at harvest by setting the combine to blow out as much
lightweight material as possible. Those thinking of saving seed
should first determine the level of scab in the field, have the
seed cleaned, do a germination test, and consider using a seed
treatment.
--
Communicated by:
ProMED-mail
<promed@promedmail.org>
[2] Nebraska
Date: Sat 5 Jul 2008
Source: KMEG 14, Associated Press (AP) report [edited]
<http://www.kmeg14.com/Global/story.asp?S=8622880&nav=menu609_2_4>
Wheat scab in Nebraska for second year in a row
The wet spring [2008] has nurtured scab in Nebraska wheat
fields.
Scab, also known as fusarium head blight, plagued the fields
last year [2007] as well. The disease can cost farmers much of
their crops if their grain is rejected because of toxins the
fungus can produce.
Normally scab is found in south-central and eastern Nebraska,
but this year it has shown up as far west as Imperial.
Plant pathologist Stephen Wegulo says it's too close to harvest
for growers to combat the problem this year. He says scab is
fought by planting tolerant cultivars, rotating crops, and
applying fungicide at early flowering.
--
Communicated by:
ProMED-mail
<promed@promedmail.org>
[Fusarium head blight (FHB; also known as 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 vomitoxin,
which can affect stock and may lead to reduced feed consumption
or feed refusal. Disease management includes timely fungicide
applications and crop varieties with reduced susceptibility.
For more information on FHB please see links and previous
ProMED-mail posts listed below.
Maps
USA:
<http://www.mapsofworld.com/usa/usa-road-map-enlarge-view.html>
and
<http://healthmap.org/promed?v=40,-97.6,4>
US states:
<http://www.census.gov/geo/www/us_regdiv.pdf>
Pictures
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>
FHB-damaged kernels of wheat, barley, and oats:
<http://sci.agr.ca/charlottetown/images/wheatseedfhbt.jpg>
Links
Additional news stories:
<http://sheridanexpress.blogspot.com/2008/06/wheat-scab-in-missouri.html>,
<http://www.dtnprogressivefarmer.com/dtnag/view/blog/getBlog.do?blogHandle=inothermedia&blogEntryId=8a82c0bc1a50b2dd011adb2d59d206dd>
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>
and
<http://www.cdl.umn.edu/pubs/pdfs/HCK/Pathogen_Profile.pdf>
Information on the mycotoxins via:
<http://cropwatch.unl.edu/>
Taxonomy of all FHB fungal pathogens via:
<http://www.indexfungorum.org/Names/Names.asp>.
- Mod.DHA]
[see also in
the
archive:
Fusarium head blight, wheat - USA (KS) 20080621.1926
2007
----
Seedling blight, cereals - UK 20071130.3860
Fungal head blights, wheat - UK 20070816.2674
Fungal blights, wheat, corn & chickpea - USA (NB, MT)
20070621.2000
2005
----
Fusarium head blight, wheat - USA (MN, ND) 20050812.2366
Wheat diseases, cereals - USA (ND) 20050731.2227
Wheat diseases - India 20050615.1683
2002
----
Fusarium head blight, oats - Canada (Manitoba) 20021017.5573
2001
----
Fusarium head blight, wheat - USA (Michigan) 20010725.1452
2000
----
Fusarium head blight: biological control 20000824.1416
Fusarium head blight, cereal - Canada (Manitoba) 20000823.1405
Fusarium head blight fungicide approved - Canada 20000624.1038
1999
----
Scab disease, wheat - Canada, USA 19990508.0756
Scab-resistant wheat, McVey cultivar - USA 19990801.1311] |
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