20 September 2000
No brown rot spread in Perth

By FWi staff

SCIENTISTS have to date found no evidence that the bacterium which causes potato brown rot discovered in a Perthshire watercourse has spread any further.

The bacterium Ralstonia solancearum was found for the first time in Scotland last week, near Carsie in the Lunan Burn, which eventually flows into the River Tay.

Extensive testing of potato tubers on farms on both sides of the watercourse showed no evidence of brown rot.

Subsequent tests have been carried out for outbreaks of the disease, other infected watercourses and the source of the bacterium.

A Scottish Executive spokesman on Wednesday (20 September) said these had found no trace of the brown rot, nor evidence of the bacterium in other watercourses.

He added that tests were also continuing to establish the source of the outbreak.

Only one field being grown for seed was irrigated from the affected watercourse, and these crops were withdrawn from seed use.

A ban will also be introduced on water abstraction from the watercourse for potato irrigation. This is likely to last for at least three years.

The Scottish Executive has written to importing countries of Scottish seed potatoes to reassure them about the brown rot-free status of Scottish seed potatoes.

A spokesman for the Scottish Potato Trade Association said: “The key point at this stage is that the infection has not been found in any crop of Scottish potatoes.”

The SPTA suspects contaminated imports may be the source of the outbreak.

The disease can be introduced to waterways through the discharge of water used to wash infected potatoes.

Potato brown rot causes leaves to wilt, and stains and rots tubers but, according to the government, has no known implications for humans.