23.3 Symbiosis in Kingdom Fungi

Symbiotic Relationships in Kingdom Fungi

Symbiotic associations between fungi and algae or plants are important mutualistic relationships in Earth's ecology.
Mutualism: A type of symbiosis in which each partner benefits.
- Fungus provides minerals it has absorbed.
- Algae or plant provides the ability to use sunlight to power the building of carbohydrates.

Mutualistic relationship between vascular plant roots and fungi.
- Fungus transfers phosphorus and other minerals from the soil to the roots.
- Plant provides carbohydrates to the fungus.
Often involves a zygomycete and a plant.
- Hyphae either wraps around the plant root or penetrates its outer cells.
Integral in the land invasion of plants by enabling them to grow in infertile soil.
Pivotal in the growth of many commercially important trees, including willows, oaks, pines, and beaches.
Some Mycorrhizae of Ascomycetes produce an edible fruiting body known as a truffle.

Symbiotic relationship between a fungus and a photosynthetic partner such as cyanobacterium, green algae, or both.
- Photosynthetic partner provides carbohydrates to the fungal partner through photosynthesis.
- Fungus provides mineral nutrients back to the photosynthetic partner.
The photosynthetic partner is often concealed inside the layers of hyphae of the fungus, which is usually an ascomycete.
This partnership enables both to survive in harsh conditions, such as desert regions, the Arctic, bare soil, tree trunks, and sunbathed rocks.
Lichens are also able to survive drought and freezing by becoming dormant, and when moisture and warmth return, they resume their normal activities.
Lichens break down rocks into soil matter, considered important for primary succession.
Lichens are susceptible to chemical changes in their environment and therefore have become good living indicators as to whether pollution or other chemicals are present.