Staghead / white rust (Albugo candida)

Staghead / white rust: biology

Thick-walled spores form in stagheads and survive in soil or with seed. Young plants are infected and spores produced in white rust pustules spread the disease.

Stagheads are conspicuous spiny deformations and swellings of individual pods or whole flowering stems. They may be green or have a white growth on the surface, but eventually turn brown to black. Earlier in the season white blistered pustules appear on the underside of leaves and sometimes on stems.

Less seed is produced because stagheads replace pods. Leaf lesions make plants less productive.