( Erwinia caratovora )
Blackrot affected plant looks pale and weak Base of stem blackened and falls over
Blackleg is caused by a bacteria with many strains which also infect stored potatoes, carrots, bulbs, and damaged plant tissue, causing Soft Rot by dissolving the cell walls. When it affects potato crops, the foliage turns yellow, the base of the stems turn black and rot, then collapse. Then it travels along the underground stems to the developing tubers which get a brown or grey, slimey rot inside. If not removed they will infect other tubers later when they are stored.
Tuber flesh rots and has a distinctive smell.
It is more prevelant during periods of increased temperature and humidity. There is no treatment so prevention is the only measure that can be taken.
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