Mutualism: A Relationship That Benefits Both Species
- Mutualism plays a crucial role in ecosystem stability, enhancing survival, growth, and reproduction.
Root Nodules in Fabaceae (Legume Family)
- Most plants cannot use atmospheric nitrogen (N2) directly.
- Legumes (e.g., peas, beans, and clover) form a mutualistic relationship with nitrogen-fixing bacteria (Rhizobium) to overcome this limitation.
How It Works
- Root Nodule Formation: Legumes develop root nodules, which provide a habitat for Rhizobium bacteria.
- Nitrogen Fixation: Rhizobium converts atmospheric N2 into ammonium (NH4), which plants can absorb and use for growth.
Benefits to Both Organisms
- Legumes: Receive a steady supply of nitrogen, boosting growth and survival in nitrogen-poor soils.
- Rhizobium: Gains a protected environment inside the root nodules and receives sugars and nutrients from the plant for energy.
Farmers use crop rotation with legumes to naturally replenish soil nitrogen.
TipMutualism differs from parasitism because both species benefit, while in parasitism, one species suffers.
Mycorrhizae in Orchidaceae (Orchid Family)
- Orchids cannot germinate and survive alone in the wild.
- Instead, they rely on a mycorrhizal relationship with fungi, particularly in nutrient-poor environments.
How It Works
- Fungal Hyphae Penetration: The fungus grows into the orchid’s roots, forming a network around root cells.
- Nutrient Exchange: The fungus absorbs nutrients (nitrogen, phosphorus, water) from the soil and transfers them to the orchid.
