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: Mon 14 Feb 2022
Source: The Beatsheet [summ. Mod.DHA, edited]
https://thebeatsheet.com.au/ergot-reported-in-southern-queensland-sorghum-crops/


The Queensland Department of Agriculture & Forestry (DAF) has recently received reports of ergot on sorghum panicles in southern areas of the state. The disease is caused by the fungus _Claviceps africana_. Infection can result in poor seed set, lower grain quality and can also cause harvesting issues due to the sticky honeydew.

Farmers are advised to keep an eye out for stickiness on seed heads. Wet weather can cause the honeydew to turn white. If any symptoms in sorghum crops are suspected, growers are requested to contact DAF for further information on disease diagnosis.

[Byline: Lisa Kelly]

--
Communicated by:
ProMED

[The parasitic fungus _Claviceps africana_ is the main cause of sorghum ergot in Africa, Asia, and the Americas. In Australia, it was first identified in 1996 and was subsequently confirmed in all national sorghum producing regions within less than a year. Other locally confined pathogens causing similar symptoms are _C. sorghi_ in India and _C. sorghicola_ in Japan. Symptoms include honeydew oozing from the flowers; developing seeds are replaced by hard sclerotia (ergots). The fungal exudate is not as sticky as that produced by aphids but may support secondary infections by other fungi and causes problems during harvest. Infection reduces grain yield and quality, with losses of up to 80% reported. The fungus also produces mycotoxins affecting cattle, pigs, and chickens. Dry conditions favour ergot formation.

The fungus can be spread via spores by wind and mechanical means, or via ergots with plant material and soil. It survives in dried honeydew on soil or plant material, as well as sclerotia in seed lots. The ergots are extremely hard and durable structures and remain viable for a long time. Disease management may include the use of certified seed, cultural practices, and fungicide treatments of seed and planted fields. No commercial ergot-resistant sorghum cultivars are available so far.

The related fungus, _C. purpurea_ affects mainly rye and triticale but also wheat, barley, and about 60 genera of grasses. Its toxins are extremely poisonous to both humans and livestock. Other species in the genus affecting a number of cereal crops produce different alkaloids. Some ergot alkaloids are also used for pharmaceutical applications and ergots are grown commercially for this purpose.

Maps
Australia (with states):
https://www.nationsonline.org/maps/australia-political-map.jpg and
https://promedmail.org/promed-post?place=8701606,285

Pictures
Ergot on sorghum:
https://content.peat-cloud.com/thumbnails/ergot-of-sorghum-1.jpg,
http://plantclinic.tamu.edu/files/2011/09/Sorghum-Ergot.jpg, and
https://www.daf.qld.gov.au/__data/assets/image/0011/54479/sorghum-ergot_rdax_90.jpg
_C. purpurea_ on rye:
http://botit.botany.wisc.edu/toms_fungi/images/clav1.jpg

Links
Disease & pathogen information, ergot of sorghum:
https://www.cabi.org/isc/datasheet/13787,
https://www.randagri.co.za/2021/06/07/sorghum-ergot-fact-sheet-two/,
https://cropwatch.unl.edu/plantdisease/sorghum/ergot (with pictures),
https://doi.org/10.1094/APSFeature-1998-06,
https://doi.org/10.1080/03235400601036612,
https://www.apsnet.org/edcenter/apsnetfeatures/Pages/Ergot.aspx,
https://www.daf.qld.gov.au/business-priorities/agriculture/plants/crops-pastures/broadacre-field-crops/sorgum-disease-managment/biology-management-toxicity-sorghum-ergot,
https://www.ars.usda.gov/ARSUserFiles/81/ErgotDVDtranscript.pdf,
https://agrilifeextension.tamu.edu/library/farming/sorghum-ergot-field-identification/, and
https://agrilifeextension.tamu.edu/library/farming/sorghum-ergot-new-disease-threat-to-the-sorghum-industry/
_C. africana_ taxonomy & synonyms:
http://www.indexfungorum.org/Names/NamesRecord.asp?RecordID=355279 and
http://www.speciesfungorum.org/GSD/GSDspecies.asp?RecordID=355279
Ergots of other crops:
http://www.entheology.org/edoto/anmviewer.asp?a=37&z=5
- Mod.DHA]

See Also

2018
----
Ergot, wheat - USA 20180827.5989240
2013
----
Ergot, barley - New Zealand: (North Island) 20130325.1601562
2009
----
Ergot toxicity - Uganda: Kabale, susp.
2008
----
Ergot, sorghum - Australia 20080125.0307
2007
----
Smut, sorghum - Uganda: (Karamoja) 20071216.4051
Ergot & stripe rust, cereals - USA (MT) 20070706.2144
2001
----
Ergot, sorghum - USA (Florida) 20011124.2876
2000
----
Sorghum ergot isolates: EPPO report 20001215.2197
1999
----
Sorghum ergot - Mexico, USA 19990514.0783
1997
----
Sorghum ergot spreading - Americas 19970725.1562
and additional items in the archives

Website: http://www.isid.org

Published: February 24, 2022