Bean Rust

Bean rust is a fungal disease caused by the fungus Uromyces appendiculatus, which attacks the leaves, stems and pods of bean plants.

Bean rust is a fungal disease caused by the fungus Uromyces appendiculatus, which attacks the leaves, stems and pods of bean plants.

If not controlled in time, excessive infection eventually leads to death of plant or plant parts, causing huge losses.


The pathogen overwinters in infected plant debris and produces spores when conditions are favorable. These spores are blown by wind to healthy plants, where they initiate infection.

Symptoms start appearing within 7-15 days of initial infection, and the earlier the infection time, the greater the potential for yield reduction.


  • The disease can infect any above ground part of the plant but mostly, symptoms are numerous on the undersides of leaves.
  • Symptoms begin as tiny white and slightly raised spots which break open, becoming distinct circular reddish brown spots which are surrounded by yellow rings on some varieties. Heavy infections cause defoliation.
  • Infected pods develop red-brown powdery pustules, surrounded by a yellow halo. As infection progresses, the pods become deformed.


Bean rust can be controlled and/or managed through several ways. These include;

Chemical method– this involves the use of fungicides. These fungicides include the following;

  • BRADLEY 500SC 10ml/20l
  • DOMAIN 250EC 10ml/20l
  • DUCASSE 250EW 20ml/20l
  • EXEMPO CURVE 250SC 15ml/20l
  • EXPLORER 3SL 10ml/20l
  • JUPITER 125SC 15ml/20l
  • MILESTONE 250EC 10ml/20l
  • MILLIONAIRE 690WDG 40g/20l
  • PROVIDENCE 400WP 50g/20l
  • RANSOM 600WP 15g/20l
  • TOMAHAWK 250EC 10ml/20l
  • TRINITY GOLD 425WP 50g/20l
  • ABSOLUTE 375SC 10ml/20l
  • COLONIZER 440WP 50g/20l


  • Whenever spraying, the fungicide should be mixed with INTEGRA 3ml/20l. This is a sticker, spreader and penetrant which improves the efficacy of the chemical.
  • Timely application of fungicides is highly important.
  • Alternating different fungicides within a crop season is recommended in order to prevent the pathogen from gaining resistance towards either of the chemicals.

Other management practices include;

  • Crop rotation with nonhost crops
  • Planting resistant varieties
  • Maintenance of field sanitation
  • Proper weed management
  • Planting certified seeds

[vc_column width=”1/4″][vc_column width=”1/2″]Last Updated: [last-modified]
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Last updated on Wednesday, March 8, 2023 at 1:32 pm

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