Treatment with a recommended fungicide may be necessary. Infection only occurs under moist air conditions or if standing water is left on the foliage for prolonged periods. Affected plants collapse and die. Damping off fungi also cause seed decay. This should not occur in proper conditions.
Viruses multiply only in living plant cells.
These parasitic micro-organisms are spread by certain sucking insects, on tools or through handling. They seldom cause serious problems with house plants. They cause root and stem rots, wilts, leaf spots and galls on the different plant parts. To reduce the chances of bacterial infection, soil sterilization and good cultural practices are essential. Nematodes are microscopic pests that burrow into root tissue or foliage.