A case of potato brown rot has been confirmed in the Irish Republic for the first time, sparking a major alert across the industry.

The disease, which has been termed the foot and mouth of the potato sector, has been identified on a farm in the south-east of the country. Supplies have been recalled and the movement of all stocks halted as an army of inspectors from the department of agriculture tries to trace the source of the infection.

Brown rot poses no risk to animal or human health but is highly infectious and, if allowed to spread, could have devastating consequences for the £56 million Irish industry and its 700-plus growers. It could also affect the previously high-grade status enjoyed by Irish seed exports.

The usual source of the disease is infected seed or water. In this case, the disease was initially detected in water samples taken at a potato packing premises as part of the department’s routine control programme. It was then traced back to a substantial player in the Irish industry, which also supplies seed.

These supplies have been recalled for testing and the movement of all stocks on the farm and at packhouses halted, in a bid to prevent the disease spreading. Extensive sampling is being carried out at the farm by department inspectors, but so far the source of the infection has not been identified.

Growers across the republic have been put on alert by the department, and urged to report any signs or suspicions of the disease. “We are working closely with the industry to ensure the outbreak is brought under control as quickly as possible,” said a spokesman.

Brown rot is caused by a bacterium called ralstonia solanacearum. Plants start to wilt shortly after infection, stems become discoloured and the plants eventually die. Potatoes that are affected have a sticky ooze on the eyes and heel of the tuber.

Detection of the disease and the current alert could scarcely have been more ill-timed. Horticulture minister Trevor Sargent has just announced a grant aid programme to develop “a vibrant potato seed sector”, which he said is critical for the future of the industry. Funding of around £1.4m is aimed at improving the production and marketing infrastructure through investment.