Introduction to Plant Diseases

There are many types of organisms that cause plant diseases, but fungi are the most common cause of dieases in landscape plants. A susceptible host plant, a virulent pathogen, and a favorable environment must be present for plant diseases to occur. The amount of overlap among these three components determines the severity of the disease. A specific chain of events must occur for diseases to develop. This process includes pathogen inoculation, penetration, infection, incubation, reproduction, and survival. Gardeners and landscape managers will need to manipulate at least one of the three diseases components to reduce disease severity in landscapes.