Blackleg potato disease symptoms are blackening and rotting at the base of the stem of potato plants. Soft, slimy rot often starting at stem end of tuber. It is hollowing above the blackened area.
Other symptoms are stunting and yellowing of the foliage, and upward curling of leaflets.
As the disease progresses the potato plant wilts and dies. The bacteria survive in plant residues remaining in the soil, are transmitted by flow water, and can transmit infection to neighboring plants. The disease penetrates through cracks in the tubers and lenticels.
It is more prevalent during periods of increased temperature and humidity. There is no treatment of blackleg potato disease so prevention is the only measure that can be taken.

Management and control

• Plant whole seed that is free from blackleg. Plant in well-drained soil, especially when using cut seed.

• Process cut seed with approved fungicides then plant immediately or suberize it well before planting to reduce infection blackleg potato disease.

• Always do plant potatoes on fields with at least two or three years between potato crops.

• Avoid excessive irrigation to prevent seed-piece decay and subsequent stem invasion.

• Remove potato culls and other plant refuse to avoid insect transmission.

• Frequently clean and disinfest seed cutting and handling equipment as well as planters, harvesters and conveyers to eliminate contamination.

These simple arrangements can help to prevent your potato plants from infection of blackleg potato disease.