( Itersonilia pastinaceae )
Parsnip canker is caused by various fungi, the main one being Itersonilia pastinaceae they are found in soil and the spores enter through damaged areas. This damage can be when the parsnips are attacked by Carrot Root Fly larvae. The top of the root develops a rusty colour, which eventually rots and can spread throughout the plant.
The infection usually occurs in the autumn as the roots mature. Sowing later to avoid root fly damage and earthing up to prevent spores washed down from the foliage are two measures which can be taken to reduce the problem. Any affected parsnips should be removed to prevent spread. Alkaline soil is less prone to carry the disease and some cultivars are more resistant.
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