Pacific Pests, Pathogens and Weeds - Online edition

Pacific Pests, Pathogens, Weeds & Pesticides

Bean charcoal rot (315)

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  • Worldwide distribution. On beans, capsicum, cocoa, cucurbits, Caribbean pine. Minor fungal disease.
  • Watery rot at ground level, spreading up the stem and into roots, causing wilts. On older plants, spots have ash-grey centres with dark margins. Black spots on seedling may girdle stems.
  • Forms 'sclerotia' - balls of the fungus with black protective skin - giving stems sooty or charcoal look.
  • Spread with movement of soil or plant debris containing sclerotia, and by seed. Sclerotia live up to 3 years.
  • Cultural control: site nursery far from production areas; use pasteurised soil or soilless mixes; nursery hygiene; check seedlings for spots; in field, sterilise soil under tarps (30 days); 3-year rotation (maize, sorghum); avoid planting next to diseased beans; ensure rapid plant growth ( good tillage, nutrition, weed); collect and destroy trash after harvest.
  • Chemical control: treat seed with thiram.
Common Name

Bean charcoal rot, ashy stem blight, damping-off, bean blight

Scientific Name

Macrophomina phaseolina. Previously known as Macrophoma phaseoli, Macrophoma phaseolina, Macropshomina phaseoli, Rhizoctonia bataticola, Sclerotium bataticola.

AUTHORS Grahame Jackson & Eric McKenzie 
Information from Charcoal rot of bean/tobacco (Macrophomina phaseolina). Plantwise Knowledge Bank. (; and Diseases of vegetable crops in Australia (2010). Editors, Denis Persley, et al. CSIRO Publishing; and from Macrophomina phaseolina (2021). Wikipedia. ( Photo 1 David B. Langston, University of Georgia, Photo 2 Clemson University, USDA Cooperative Extension Slide Series, Photo 3 Paul Bachi, University of Kentucky research and Education Center,

Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.

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