FRENCH BEAN RUST

The section showing french bean rust spores scrapped and viewed under foldscope, ICAR-NOFRI,Sikkim.

Bean rust is a fungal disease caused by Uromyces appendiculatus of the foliage, spread by airborne spores. Infection is favoured by wet weather conditions.

Symptoms:

• Initially, pale, raised spots appear on the upper leaf surface, corresponding to small white pustules on the lower surface. As summer progresses, tiny brown and then black pustules form on the lower leaf surface, often in great numbers. The black pustules also form on the upper surface. Pods may also be affected.
• Heavily infected leaves turn brown and die, and severely affected plants may be stunted. It can also lead to shrivelling and shedding of leaves .