[Ropster]

anyone know what this is and if it is harmfull

[mumofstig]

Have alook here to see if you can identify what it is

potato diseases

[RIKJD89]

That link has put me right off my chips!

[Ropster]

yes I have looked at that site but cant see anything similar

[Jay The Digger]

Try this.

http://www.potato.org.uk/department/knowledge_transfer/pests_and_diseases/ref.html?item=40

Internal Browning.  Looks like this even has the experts stumped.  Is the whole crop affected or just the odd one?

[davethespread]

i just consulted a book i have and it looks like something called spraing apparently caused by trace element deficiency or water shortage.
hope this is of help.