The mutualistic, symbiotic relationship between a fungus and the roots of a plant is called Mycorrhizal association. This relationship is beneficial for both the plant and the fungus. Here's why:
1. **Nutrient exchange**: The fungus helps the plant absorb essential nutrients like phosphorus and nitrogen from the soil, which may be difficult for the plant to obtain on its own.
2. **Water absorption**: The fungal hyphae (filaments) extend into the soil and increase the surface area for water absorption, helping the plant during times of drought.
3. **Plant growth**: By forming mycorrhizal associations, plants can experience improved growth, better resistance to diseases, and increased tolerance to environmental stresses.
4. **Types of mycorrhizae**: There are different types of mycorrhizae, with arbuscular mycorrhizae being the most common and forming associations with the roots of a wide range of plants.
Therefore, in the context of the question, the correct answer is Mycorrhizal. It signifies the important relationship between certain fungi and plant roots, showcasing the interconnectedness and interdependence of organisms in ecosystems.
