Bacterial soft rot of chrysanthemum

'Bacterial soft rot of chrysanthemum, caused by E. chrysanthemi, is a soft rot pathogen degrading succulent fleshy plant organs such as roots, tubers, stem cuttings and thick leaves. It is also a vascular wilt pathogen, colonizing the xylem and becoming systemic within the plant. This latter aspect is the most alarming when vegetative propagation is involved. The pathogen can remain latent in stock plants and can thus be spread in cuttings from them. Tubers are an important source of the disease for potatoes.

Symptoms
Since soft rots and particularly wilts are not symptoms specific to E. chrysanthemi, the identity of the causal bacterium must be checked.

Control
Control varies with the crop attacked. It entails strict attention to sanitation and plant hygiene in the nursery or glasshouse, and usually a rigidly controlled propagation programme to produce disease-free plants.