mykorritasien

Mycorrhizas are symbiotic associations between fungi and plant roots that are found in the vast majority of land plants. In a mycorrhizal relationship, the fungal partner colonizes the root system and extends its hyphae into the surrounding soil, increasing the surface area for water and nutrient absorption while receiving carbohydrates from the plant. In Finnish, this group is known as mykorritasien.

There are several main forms. Arbuscular mycorrhizae (AM) are formed by fungi in the phylum Glomeromycota and penetrate root cortical cells to form arbuscules and sometimes vesicles. They are the most widespread type, associating with many agricultural crops and temperate grasslands, and they principally aid phosphorus uptake and micronutrient acquisition. Ectomycorrhizae (ECM) involve fungi such as members of the Basidiomycota and some Ascomycota; they form a sheath around the root tip and a network called the Hartig net between outer root cells. ECM are common in many trees, including pines and oaks, and often enhance nitrogen uptake in exchange for plant carbon. Ericoid mycorrhizae (ERM) occur in ericaceous plants and use very fine hyphae to access organic forms of nutrients in litter and soil. Orchid mycorrhizae are specialized associations essential for seed germination and early development in many orchid species, with the fungus providing carbon and nutrients during the seed’s seedling stage.

Ecologically, mycorrhizal networks can connect multiple plants, influence nutrient cycling, and contribute to soil structure through hyphal mats and soil proteins such as glomalin. In agriculture and restoration, mycorrhizal inoculation and sustainable management can improve nutrient efficiency, drought tolerance, and soil health, though benefits depend on plant species, soil conditions, and nutrient availability.