Common Scab affects Potato Tubers.
Common Scab (Latin name - Streptomyces scabies) causes the skin of potatoes to develop dark, scaby patches which can cause pitting or cracking of the skin.
The disease is only skin deep and the eating quality is unaffected.
Common scab is caused by soil borne bacteria.
Common Scab occurrs when the soil is:
- light and sandy
- alkaline
- deficient in organic matter
- dry at tuber initiation
Prevention of Common Scab:
- plant healthy seed with clean skins
- grow resistant varieties such as King Edward, Pentland Crown, Pentland Javelin & Maris Peer
- do not lime the soil before planting potatoes
- dig in compost or other organic matter to help preserve moisture
Treatment:
- there are no sprays for common scab in potatoes
I get scab because my soil’s rather light. I don’t find it affects taste or storage potential, though. Of all the potato problems, it’s the one that worries me least. It’s this wretched blight that blows my mind!
Comment by Soilman - August 2, 2007 6:23 am
Hi Soilman
I agree - and what a blighty year we are having!
TopVeg
Comment by TopVeg - August 2, 2007 6:53 am