Juurisymbioosit

Juurisymbioosit refers to symbiotic relationships between plants and fungi that occur in the root systems of plants. These associations are mutually beneficial, meaning both the plant and the fungus derive advantages from the interaction. The most common type of juurisymbioosi is mycorrhiza, a term derived from Greek words meaning "fungus" and "root".

There are two main types of mycorrhizae. Ectomycorrhizae form a sheath of fungal hyphae around the root tip and penetrate the spaces between root cells, but not into the cells themselves. This type is commonly found in association with trees like pines, oaks, and birches. Endomycorrhizae, also known as arbuscular mycorrhizae (AM), penetrate directly into the root cells, forming branched structures called arbuscules within the cells where nutrient exchange occurs. AM fungi are widespread and associate with a vast majority of plant species, including many crops, vegetables, and grasses.

In these symbiotic relationships, the fungus enhances the plant's ability to absorb water and nutrients, particularly phosphorus and nitrogen, from the soil. The extensive network of fungal hyphae increases the surface area for absorption, effectively extending the plant's root system. In return, the plant provides the fungus with carbohydrates, such as sugars produced during photosynthesis, which the fungus cannot produce itself. This exchange of resources is crucial for the survival and growth of both partners, especially in nutrient-poor environments. Juurisymbioosit play a vital role in terrestrial ecosystems, influencing plant community structure and soil health.