Broad Bean Rust Disease

photo: susanne wiik

Broad Bean Rust.

• I used to get rust on my broad beans, but last year I sprayed them with aerated compost tea, and escaped the usual infestation.
• In our climate, rust starts to affect the leaves of our broad beans as the pods mature.

Details.

• Binomial name:                                 Uromyces viciae-fabea var. viiae-fabae
• Family:                                             Pucciniaceae.

Why Broad Bean Rust is a pest.

• Severe infestations will defoliate a broad bean plant leading to premature harvest, or even total loss of the crop.
• The disease is caused by the fungus Uromyces viviae-fabae which is usually transmitted by air, water or insect vectors.
• The fungal hyphae invade the plants structure and feed on nutrients in the plant. This leads to partial defoliation.
• Fungal spores can overwinter in dead organic matter and the soil surrounding infected plants. It is not a good idea to add this material to your compost unless you can be sure the compost will generate enough heat to kill the fungi.

Pest Control

• Last year I sprayed my broad beans and peas with aerated compost tea. For the first time in many years they were not attacked by broad bean rust.
• Aerated compost tea contains beneficial nematodes and protozoa which are predators feeding on bacteria and fungi on the plant's stems and foliage.
• Use a 4 year crop rotation which moves broad beans and peas to a new bed each year and deprives rust spores of their prey.
• If you do get rust on your broad beans or peas, remove any infected leaves and destroyed them before the fungi spreads to the whole crop.