mycorrhizán

Mycorrhizan is a term that can refer to a few related concepts, primarily concerning symbiotic relationships between fungi and plants. In its most common usage, it refers to the symbiotic association between a fungus and the roots of a vascular plant. This relationship is crucial for the survival and growth of many plants. The fungus extends its hyphae (thread-like structures) into the soil, significantly increasing the surface area for nutrient and water absorption. In return, the plant provides the fungus with carbohydrates, such as sugars, produced during photosynthesis.

There are two main types of mycorrhizae. Ectomycorrhizae form a sheath around the root tips and grow between the root cells, but do not penetrate them. They are common with trees like pines and oaks. Arbuscular mycorrhizae, also known as endomycorrhizae, penetrate the root cells, forming tree-like structures called arbuscules where nutrient exchange occurs. These are far more common, found in about 80% of plant species, including many crops.

The benefits of mycorrhizal associations are numerous. Plants with mycorrhizae are generally more resistant to drought, disease, and soil toxins. The fungi can also help mobilize nutrients that are otherwise unavailable to plants, such as phosphorus and nitrogen. This symbiotic relationship plays a vital role in ecosystem health and productivity, influencing plant community structure and soil fertility. The study of these fungal associations is known as mycorrhizal ecology.