Mycorrhizal fungi: the symbiotic friends of plants

Plants perform photosynthesis, using sunlight to convert carbon dioxide and water into food for growth, flowers, seeds, and new plants, while releasing oxygen essential for life. While most life depends on plant photosynthesis, plants also need minerals from the soil for healthy growth. Soils must contain adequate nutrients, which plants absorb through water. These nutrients, sourced from decaying organic matter, the atmosphere, and rocks, are vital for all living organisms, as animals feed on plants and we rely on both plants and animals for food.

Minerals such as nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur are present in low quantities in soil, often leaving plants nutrient-starved. Fortunately, plants receive help from microorganisms like rhizobia, which fix nitrogen, and fungi that form symbiotic relationships with plant roots. Over 90% of land plants, including crops like rice, wheat, tomatoes, and fruits like apples, host arbuscular mycorrhizal fungi (AM fungi), while trees like pines and oaks associate with ectomycorrhizal fungi (ECM fungi).

These fungi expand the plant's root system, acquiring minerals from the soil and providing them to the plant. In return, the plant supplies organic carbon from photosynthesis to the fungi. This mutual relationship also protects plants from harmful microbes, demonstrating a powerful example of cooperation among organisms.