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Introduction to Organisms

Author(s): Deanne Erdmann, MS

Ecological Importance of Fungi

As major decomposers, fungi serve an important role in ecosystems. Without decomposition, there would not be enough available nutrients to sustain or create new life. 

Many fungi are parasites and thrive on living things, which is an association harmful to the host. Fungi cause plant diseases such as black spot, corn smut, wheat rust, and mildews that affect a variety of fruits. Most of us are familiar with fungi that cause human discomforts like athlete's foot, ringworm, and thrush.

Other kinds of fungi live together in a mutually beneficial relationship with other organisms. Lichens are symbionts of a fungus and a green algae, or a cyanobacterium. Mycorrhizae are mutualistic relationships between fungi and the roots of vascular plants. Fungi cells supply the plant with more nutrients and water than normally would be absorbed by the roots alone, and the plant provides the fungus with products of photosynthesis.