Mycelium refers to the vegetative part of a fungus, consisting of a network of fine white filaments (hyphae). This structure plays a crucial role in the decomposition of organic matter in the ecosystem, enabling fungi to absorb nutrients from the environment. Mycelium types can vary based on their associations with other organisms, their structure, and their function. Here are some common types of mycelium and their characteristics:
Saprophytic Mycelium
This type of mycelium decomposes dead organic material, breaking it down into simpler substances. Saprophytic fungi are critical for nutrient cycling in ecosystems.
Parasitic Mycelium
Parasitic fungi depend on living organisms to survive, often to the detriment of their hosts. They penetrate host tissues to absorb nutrients, sometimes causing diseases in plants and animals.
Mycorrhizal Mycelium
Mycorrhizae form symbiotic associations with the roots of most plant species. There are two main types:
- Ectomycorrhizal fungi (ECM) form a sheathing layer around the roots and penetrate between root cells but not into the cells themselves, facilitating nutrient exchange.
- Arbuscular mycorrhizal fungi (AMF) penetrate the root cells, forming arbuscules within them, which are key sites for nutrient exchange between the fungus and the plant.
Endophytic Mycelium
These fungi live inside plants without causing any apparent disease symptoms. They can provide benefits to the host plant, such as increased resistance to pathogens, drought, and heavy metals.
Rhizomorphic Mycelium
Characterized by its root-like structures, rhizomorphic mycelium is efficient in nutrient and water absorption. It’s often associated with fungi that form large, complex fruiting bodies.
Tomentose Mycelium
This type forms dense, cottony mats that are less organized than rhizomorphic mycelium. It’s commonly found in the early growth stages of many fungi.
Dimorphic Mycelium
Some fungi can switch between yeast-like growth and filamentous growth depending on environmental conditions. This versatility allows them to adapt to varying environments.
Each type of mycelium plays a distinct role in its ecosystem, whether it’s decomposing organic matter, forming symbiotic relationships with plants, or surviving in a parasitic manner. The diversity of mycelial forms reflects the wide range of habitats and ecological niches that fungi occupy.