Ericoid mycorrhiza

Ericoid mycorrhiza is a type of symbiosis between certain species of fungi and the roots of plants in the family Ericaceae, which includes heathers and their relatives. This mutualistic relationship is characterized by the fungus colonizing the root cells of the host plant, forming a structure known as an ericoid mycorrhizal root. This association is particularly important for nutrient uptake in poor soils, where these plants often grow.

Characteristics

Ericoid mycorrhizae are distinguished by the penetration of the fungal hyphae into the root cells of the host plant, forming a dense network called a hyphal coil. These coils facilitate the transfer of nutrients, particularly nitrogen and phosphorus, from the fungus to the plant. In return, the plant supplies the fungus with carbohydrates produced through photosynthesis.

Function

The primary function of ericoid mycorrhiza is to enhance nutrient uptake in nutrient-poor environments. Ericaceous plants are often found in acidic, nutrient-deficient soils, where the availability of essential nutrients like nitrogen and phosphorus is limited. The fungi involved in ericoid mycorrhizal associations are capable of breaking down complex organic materials in the soil, making nutrients available to the host plant. This ability allows ericaceous plants to thrive in environments where other plants would struggle to survive.

Ecological Importance

Ericoid mycorrhizae play a crucial role in the ecology of heathlands and other ecosystems dominated by Ericaceae. They contribute to the nutrient cycling and soil structure in these environments. Additionally, by enabling their host plants to dominate in nutrient-poor soils, ericoid mycorrhizae help to maintain the biodiversity of these ecosystems by supporting a unique flora adapted to these conditions.

Types of Fungi Involved

The fungi that form ericoid mycorrhizal associations belong primarily to the Ascomycota phylum, with some species from the Basidiomycota. Genera such as Rhizoscyphus (formerly Hymenoscyphus), Oidiodendron, and Meliniomyces are among the most commonly associated with ericoid mycorrhiza.

Research and Applications

Research into ericoid mycorrhiza has implications for ecology, agriculture, and environmental science. Understanding how these associations work can help in the restoration of degraded lands, improve the cultivation of Ericaceae plants, and offer insights into the adaptation of plants and fungi to challenging environments.

See Also

• Mycorrhiza
• Arbuscular mycorrhiza
• Ectomycorrhiza
• Orchid mycorrhiza