ANTHRACNOSE

plant disease of warm humid areas that infects a variety of plants from trees to grasses. It is caused by certain fungi (usually Colletotrichum or Gloeosporium) producing spores in tiny, sunken, saucer-shaped fruiting bodies (acervuli). Symptoms include sunken spots of various colours in leaves, stems, fruits, or flowers. The spots often enlarge, leading to wilting, withering, and dying of tissues. In the late 1970s a new form of the disease, which is known as dogwood anthracnose, was identified in North America. Unlike other forms of anthracnose, it thrives in cool climates. Dogwood anthracnose first appeared in the Pacific Northwest, and it soon spread to the eastern United States, eventually resulting in severe losses to natural stands of dogwoods in mountainous regions. The causative agent, Discula destructiva, was not described until 1991. Anthracnose can be avoided by destroying diseased parts, using disease-free seed and disease-resistant varieties, applying fungicides, and controlling insects and mites that spread anthracnose fungi from plant to plant.