Chocolate spot disease

Chocolate spot disease on faba bean

Chocolate spot disease on faba bean is caused by the fungus botrytis fabae.

Life cycle

Life cycle of Botrytis fabae on Faba bean
Life cycle of botrytis fabae on Faba bean (copyright Bernard TIVOLI, INRA).

Development of the symptoms

The disease is present on all the plants of the field.
The symptoms are visible only on the leaves and the flowers. No symptoms are present on the pods, and very few on the stems.

1.

Symptoms of chocolate spot disease on faba bean leaf
Symptoms of chocolate spot disease on faba bean leaf (copyright Bernard TIVOLI, INRA)

Numerous chocolate-coloured infection spots, measuring some millimeters in diameter, are visible on the leaves. The infection is often spread to all the nods of the plant, and all the plants of the field.

2.

Beginning of the agressive stage, coalescence of the necroses.

3.

Symptoms of chocolate spot disease on leaf
Symptoms of chocolate spot disease on leaf (copyright Bernard TIVOLI, INRA).

Extension of the primary symptoms: coalescence and necrosis of the basal foliage.

4.

Symptoms of chocolate spot disease on faba bean plant

The infection of the leaves and the flowers causes defoliation and flower drop.

Date de modification : 25 avril 2023 | Date de création : 29 août 2013 | Rédaction : Bernard TIVOLI (INRA)