Sugarcane smut (474)

Pacific Pests, Pathogens, Weeds & Pesticides - Online edition

Pacific Pests, Pathogens, Weeds & Pesticides

Sugarcane smut (474)

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Photo 1. Whip-like spore-containing structure of sugarcane smut, Sporisorium scitamineum, emerging from the top of a plant.

Photo 2. As in Photo 1, the whip-like, spore-containing structure of sugarcane smut, Sporisorium scitamineum, has completely replaced the leaf spindle of the sugarcane plant.

Photo 3. Spores (teliospores) of sugarcane smut, Sporisorium scitamineum; they are black when together on the whip, but under the microscope are brown and round.

Summary

Worldwide distribution. In Australia; note, report from Fiji incorrect.
Serious disease, often occurring in cycles: epidemics followed by minor importance. Infected plants weak, grass-like, stunted with narrow leaves and many tillers. Characteristically, shoots become black spores-bearing whip-like structures.
Lower buds infected by fungal spores from soil. Subsequently, sets planted and fungus grows within them.
Spread: infected sets and spores on the wind. Possibly, spores on machinery, footwear. Survival in soil for 3-4 months.
Biosecurity: follow FAO guidelines for international movement of sugarcane.
Cultural control: deep ploughing or irrigation of fields after outbreaks; hot water treatment (52^oC for 30 minutes or 50^oC for 3 hours); rogueing.
Chemical control: fungicides (flutriafol or propiconazole) after hot water treatment in commercial operations.

Common Name

Sugarcane smut

Scientific Name

Sporisorium scitamineum; previously known as Ustilago sacchari, and Ustilago scitaminea. Genetic diversity appears to be greatest in Asia, but whether there are strains of the fugus is more controversial.

Photo 4. Infection of sugarcane smut, Sporisorium scitamineum. 1, Teliospores; 2, Soil and/or sugarcane plants contaminated with Sporisorium scitamineum; 3, Teliospore germination; 4, Germinating spores and fungal growth; 5, Infection of sugarcane meristem (growing point); 6, The formation of diseased panicle, with whip-like growth.

AUTHOR Grahame Jackson
Information from Sugar Research Australia. Sugarcane smut. Information sheet ISI3012. (https://sugarresearch.com.au/wp-content/uploads/2017/02/Sugarcane-smut-IS13012.pdf); and CABI (2019) Sporisorium scitamineum (sugarcane smut) Crop Protection Compendium. (https://www.cabi.org/cpc/datasheet/55949); and Sugarcane smut. Wikipedia. (https://en.wikipedia.org/wiki/Sugarcane_smut); and from Dingley JM, et al. (1981) Records of fungi, bacteria, algae, and angiosperms pathogenic on plants in Cook Islands, Fiji, Kiribati, Niue, Tonga, and Western Samoa. Technical Report (2). South Pacific Bureau for Economic Co-operation, United Nations Development Programme, Food and Agricultural Organisation of the United Nations. Photo 1 William M. Brown Jr.Bugwood.org. Photos 2&3 Roger Sivas (2010) Sugarcane smut (Ustilago scitaminae: PaDIL - (http://www.padil.gov.au). Photo 4 Que Y, et al. (2014) Genome sequencing of Sporisorium scitamineum provides insights into the pathogenic mechanisms of sugarcane smut. BMC Genomics 2014(15):996. (https://bmcgenomics.biomedcentral.com/articles/10.1186/1471-2164-15-996).

Produced with support from the Australian Centre for International Agricultural Research under project HORT/2016/185: Responding to emerging pest and disease threats to horticulture in the Pacific islands, implemented by the University of Queensland and the Secretariat of the Pacific Community.

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