Introduction of Claviceps africana in South America
In mid-1995, the sugary disease of sorghum due to Claviceps africana was found in commercial forage and hybrid seed production fields in Brazil (Sao Paulo, Minas Gerais, Goias). The disease reached rapidly all the central and southern part of the country. This was the first report of C. africana in the Americas. Ergot fungi causing sugary disease (it now seems that C. africana is considered as distinct from C. sorghi) were previously only reported from Africa and Asia. The rapid dissemination of sugary disease in Brazil is of major concern to other countries of the region. The disease affects individual florets in a panicle, causing poor development of grain or preventing it. Symptoms are characterized by the presence of sticky, pinkish to brownish liquid drops, which exude from infected ovaries. A saprophytic fungus may then overgrow the honeydew and convert it into a sticky black mat. The sugary disease can cause severe losses especially in seed production fields, particularly if pollination of male-sterile lines is delayed due to lack of viable pollen. Sclerotia of the sugary disease fungus have not been reported to be toxic to humans or animals unlike the European ergot pathogen C. purpurea.
Reis, E.M.; Mantle, P.G.; Hassan, H.A.G. (1996) First report in the Americas of Sorghum ergot disease, caused by a pathogen diagnosed as Claviceps africana.
Plant Disease, 80(4), 463.
Vasconcellos,J.H. (1996) Ergot of sorghum.
ISPP International Newsletter on Plant Pathology, 26 (6), December 1996, p 1.