Wart Disease
Synchytrium endobioticum
Pathogen
Fungus
Hosts
Potatoes (can also survive on a number of wild Solanum spp.)
Symptoms
Tubers and underground stems are deformed by greenish - yellow cauliflower-like outgrowths.
Development
As the crop dies down, the outgrowths decay and release spores into the soil, where they may remain infective for more than 30 years. Spread is by contaminated machinery or tools, soil from plants grown in infested fields and manure from stock fed with infected tubers. The disease may also develop during storage.
Favourable Factors
Cool, wet soils.
Importance
As this is a Notifiable Disease, infected potato crops must be destroyed and subsequent planting of potatoes can be restricted.
Control
Most varieties are immune (with the notable exception of King Edward)
Legislation prohibits the cultivation of potatoes on infected land
New varieties are all tested for resistance to this disease
For many years strict quarantine and domestic legislation has restricted the movement of infected tubers from countries where it is present
