It is brought on by the oomycete Albugo candida or one of its near relatives.
It occurs at the place of crop cultivation.
Both wild and cultivated plants are under attack.
Plants that are susceptible to this disease typically belong to the Brassica family.
White rust has a track record of causing agricultural losses in fields where this family's members, such as broccoli, cauliflower, and Indian mustard, are planted.
The chalk-white, cheesy, elevated spore masses that most frequently appear on the underside of the leaf are an easy way to identify white rust, also known as a white blister.
The first sign of white rust is the emergence of small, erratic yellow patches on the upper leaf surface.
The disease persists from season to season as thick-walled spores (oospores) in the soil, plant debris, or both.
Crop rotation and clean tillage lessen the number of primary inoculum (spores) in the nearby area, hence lowering the risk of illness.