Mycorrhiza is a symbiotic association between a fungus and a plant, where the fungus colonizes the roots of the plant and helps it to absorb water and nutrients from the soil. The term mycorrhiza refers to the role of the fungus in the plants rhizosphere, its root system. The plant supplies the fungus with organic molecules produced by photosynthesis, while the fungus supplies the plant with water and mineral nutrients, such as phosphorus, taken from the soil. Mycorrhizae play important roles in plant nutrition, soil biology, and soil health.

There are two main classes of mycorrhizae: ectomycorrhizae and endomycorrhizae. Ectomycorrhizae are found on many evergreen trees and shrubs, and the fungus covers the ends of young roots and only penetrates the cell wall of the cortex; no further cellular penetration occurs. Endomycorrhizae, also known as arbuscular mycorrhizae, are the ancestral and predominant form, and the most prevalent symbiotic association found in the plant kingdom. The structure of arbuscular mycorrhizae has been highly conserved since their first appearance in the fossil record.

Mycorrhizae are present in 92% of plant families studied (80% of species) . They are essential in areas where soils are deficient in water and certain nutrients, such as in the desert. Even when there is an ample amount of a nutrient, it may not be readily accessible to the plant. Mycorrhizae can play an important role in plant health, and their effects can be remarkable, particularly in the case of their absence.

In agriculture, mycorrhizal fungi are partnering with plants in symbiosis to contribute to sustainably feeding our growing global population, even in drought-affected areas, salty soils, desertified farmland, etc. . Research has shown that diversity of mycorrhizae in the plant’s root system is important, as different species of mycorrhizae provide different benefits to the plant under variable circumstances.