Wounding roots of bedding plants during transplanting provides entry for root-rotting fungi. The mouthparts of an insect also result in openings for penetration. The fourth stage is infection. The pathogen grows within the plant and begins damaging the plant tissue. As the pathogen consumes nutrients, the plant reacts by showing symptoms.
Symptoms are evidence of the pathogens causing damage to the plant.
Symptoms include mottling, dwarfing, distortion, discoloration, wilting, and shriveling of any plant part. Many plant diseases survive from one growing season to the next on plant debris, seeds, alternate hosts or in soil. Because of pathogen survival, it is important to remove and properly dispose of any infected plant materials. It is also important for the gardener to know about the diseases that affect each plant throughout the home landscape, as well as the conditions needed for proper culture.