Potato growers in part of Australia have been affected by a new strain of bacterial potato wilt.

The problem has reduced interstate markets for some far North Queensland growers.

The disease, which has been found in small patches at Tolga and on parts of the Atherton Tablelands, will prevent growers within a 20-kilometre radius of the infection from exporting to Tasmania, South and Western Australia, and parts of Victoria and New South Wales.

Due to the quarantines, more growers are sending produce to Brisbane, Sydney and Melbourne causing an overload in the Eastern seaboard market, affecting price and availability.