In severe infections leaves and flowers may fall and badly affected stems may keel over.

The sclerotia germinate and conidiophores are formed, the conidia (asexual spores) are dispersed by air currents and deposited by rain on susceptible young plants.

The conidia are liberated from dead or dying leaves and flowers, usually those that have fallen to the ground, and are spread to other plants in the vicinity by wind and splashes of water.

[4] After harvest the fungus remains in a semi-dormant state in plant debris until the next growing season.

[2] Infection can be minimised by the destruction of plant debris at the end of the season, the avoidance of sites recently used for faba bean crops and the selection of cultivars with a high level of resistance to the disease.