Bacteria which causes a serious potato disease has been found for the first time in the UK, it emerged today.
The bacterium c lavibacter michiganensis sepedonicus, which causes ring rot, has been confirmed in a sample of potatoes produced from Dutch seed potatoes at a farm in mid Wales.
Information on the notifiable disease issued by the Department for Environment, Food and Rural Affairs (Defra) says that annual losses from ring rot had been as high as 50% in the US.
The Farmers' Union of Wales (FUW) said that spread of the disease could cause a "catastrophe" in the UK potato industry.
The discovery, reported on the BBC Radio 4 Farming Today programme today, is the first in the UK.
The affected potatoes came from a consignment produced as seed potatoes for export to the Canary Isles and were checked as part of the annual survey for ring rot, said Defra.
It said that if ring rot were to become established in the UK, the potato industry would suffer direct yield losses and the knock-on effect for the seed potato industry could be "substantial".
A Defra statement said: "Action is being taken to prevent any spread of the disease from the infected farm and to trace any related potato stocks."
Dutch authorities are being contacted to identify other UK locations to which seed of the same variety and origin may have gone.
Buyers of any potatoes from the affected Welsh farm will be traced and the relevant authorities informed, the department said.
It says that the disease favours cool climates and could easily become established in the UK.
FUW spokesman Alan Morris said the finding was of great concern to a farming community which had already had to endure the foot-and-mouth disease crisis of 2001.
"We hope swift action will be taken to contain and eradicate this disease before it gets a foothold and spreads," he said. "The economic consequences if it gets a grip are enormous and could cause a catastrophe in the potato industry in the UK.
"It is no risk to human health at all but the financial losses could be enormous."