Africa: widespread; Asia: India, Japan, Thailand, Yemen; North America: Dominican Republic, Haiti, Honduras, Jamaica, Mexico, Puerto Rico; Oceania: Australia; South America: Argentina, Bolivia, Brazil, Colombia, Paraguay
FL, GA, KS, MS, NE, OK, TX
2025-08-05
fungus
Korea
Main: Sorghum. Other: Johnsongrass.
CLAVAF
Claviceps africana infects flowers during or after blooming, producing a sticky honeydew and eventually dark sclerotia. It is primarily windborne but sources note sorghum seed as a pathway.
Usually associated with seed lots or sclerotia may be attached to seed coat exudates. Seed as a pathway is established but importance in spread is disputed. However, seed cleaning, storage and seed treatments has essentially eliminated seed inoculum.
Yes
Visual examination of seed
This test has not been validated or standardized.
CLAVAF-3
Seed Treatment (thiram) and Seed conditioning
Seed treatments, cleaning and seed storage for 2-3 months essentially eliminates contamination of seed by Claviceps africana.
Alderman S, Frederickson D, Milbrath G, Montes N, Narro-Sanchez J, 1999. A laboratory guide to the identification of Claviceps purpurea and Claviceps africana in grass and sorghum seed samples. Sponsored by the Seed trade Associations of Mexico, America, Oregon, Texas.
Mcleran, NW. 1993. Effect of sugary disease exudates on germination, seedling development and predisposition to seedling diseases of sorghum (Sorghum bicolor). South African Journal of Plant and Soil 10:12-16
Odvody GN, Frederickson DE, Isakeit T, Montes N, Dahlberg JA, Peterson GL, 2002. Quarantine issues arising from contamination of seed with ergot: an update. In: Sorghum and Millets Diseases ed. by Leslie JF, Iowa State University Press, Ames. Iowa, USA: pg.123-129.
Frederickson, D. E., Mantle, P. G., & De Milliano, W. A. J. (1993). Windborne spread of ergot disease (Claviceps africana) in sorghum A‐lines in Zimbabwe. Plant Pathology, 42(3), 368-377.
Miedaner, T., & Geiger, H. H. (2015). Biology, Genetics, and Management of Ergot (Claviceps spp.) in Rye, Sorghum, and Pearl Millet. Toxins, 7(3), 659-678. https://doi.org/10.3390/toxins7030659
Ahn, E., Fall, C., Botkin, J., Curtin, S., Prom, L. K., & Magill, C. (2023). Inoculation and Screening Methods for Major Sorghum Diseases Caused by Fungal Pathogens: Claviceps africana, Colletotrichum sublineola, Sporisorium reilianum, Peronosclerospora sorghi and Macrophomina phaseolina. Plants, 12(9), 1906.
Bandyopadhyay R, Frederickson DE, McLaren NW, Odvody GN, Ryley MJ, 1998 . Ergot: a new disease threat to sorghum in the Americas and Australia. Plant Disease, 82(4):356-367; 54 ref.