mikorrhízája

Mycorrhiza is a symbiotic association between a fungus and the roots of a plant. The term mycorrhiza comes from the Greek words "mykes" meaning fungus and "rhiza" meaning root. This mutually beneficial relationship plays a crucial role in nutrient uptake for most terrestrial plants.

In a mycorrhizal association, the fungus colonizes the root system of the host plant, either intracellularly or extracellularly. In return for the plant's carbohydrates, which it provides through photosynthesis, the fungus enhances the plant's ability to absorb water and essential nutrients, particularly phosphorus and nitrogen, from the soil. Fungal hyphae, which are much finer than plant roots, can explore a larger volume of soil, accessing nutrients that might otherwise be unavailable to the plant.

There are two main types of mycorrhizae: ectomycorrhizae and endomycorrhizae. Ectomycorrhizae form a sheath around the root tips, and their hyphae penetrate between the root cells but do not enter them. Endomycorrhizae, also known as arbuscular mycorrhizae (AM), penetrate the root cells, forming branched structures called arbuscules within the cells, which are the primary sites of nutrient exchange.

Mycorrhizal fungi also contribute to soil aggregation, improving soil structure and water retention. They can help protect plants from pathogens and can also facilitate communication between plants through the "wood wide web" of fungal hyphae. This intricate relationship is vital for the health and productivity of many ecosystems.