Fungal Diseases in Plants
Fungi take energy from the plants on which they live, causing damage to the plant. Fungal infections are responsible for approximately two-thirds of infectious plant diseases and cause wilting, molding, rusts, scabs, rotted tissue, and other problems.
Signs of damage
A sign of plant disease is physical evidence of the pathogen. For example, fungal fruiting bodies are a sign of disease. When you look at powdery mildew on a lilac leaf, you’re actually looking at the parasitic fungal disease organism itself (Microsphaera alni). Bacterial canker of stone fruits causes gummosis, a bacterial exudate emerging from the cankers. The thick, liquid exudate is primarily composed of bacteria and is a sign of the disease, although the canker itself is composed of plant tissue and is a symptom.