Fungi, animals, and plants have coexisted since these three groups of higher organisms originated. Living close together for a long time can cause neighbors to be at each other’s throats or in each other’s pockets. Different fungi have followed both of these routes. We have already seen how the “at each other’s throats” metaphor emerges with fungal diseases and toxins that enable fungi to have some advantage over animal and plant adversaries. But there are several fungi that have taken the opposite route by treating plants and animals as partners in mutually beneficial relationships. Scientists call such arrangements symbiosis or mutualistic associations. The organisms concerned (often two but sometimes three) live in such close proximity to each other that their cells may intermingle and may even contribute to the formation of Joint tissues. In these associations the partners each gain something from the partnership and are more successful than they would be without the association. Fungi are involved in some very ancient mutualistic associations. Lichens, basically combinations of fungi and algae, can be found in some of the most inhospitable environments. Another association is a mycorrhiza, which is a fungal infection of plant roots. At least 95 percent of land plants rely on them, especially for mineral nutrients, and in return the fungus gets some sugar formed by the plant in photosynthesis. There’s more to it than that, though.
KeywordsMycorrhizal Fungus Tall Fescue Tropical Rain Forest Ergot Alkaloid Fungus Garden
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