This disease is caused by Erwinia chrysanthemi.
The most pronounced symptom is a rot of the upper part of the stem, resulting in wilt and collapse of the distal portion. Infected cuttings may show a brown to black decay at their bases. Occasionally, the only symptom is a marginal leaf scorch.
Prevention and Treatment: Soil in which diseased plants
grew should be pasteurized with heat before reuse. Use cuttings that are disease-free, or dip cuttings for 4 hours in solutions of antibiotics such as streptomycin or aureomycin.
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