Which legume is commonly used in crop rotations to fix nitrogen?

The legume commonly used in crop rotations to fix nitrogen is soybean. Soybeans are part of the legume family and have a symbiotic relationship with specific soil bacteria, particularly Rhizobium. This relationship allows soybeans to convert atmospheric nitrogen into a form that plants can use, significantly enhancing the nitrogen content in the soil.

This nitrogen-fixing ability makes soybeans especially valuable in agricultural systems, as they can reduce the need for synthetic fertilizers, promote soil health, and improve the overall nutrient balance of the soil when rotated with non-leguminous crops. When included in a crop rotation plan, soybeans can lead to improved yields in subsequent crops due to the increased available nitrogen in the soil, which is vital for plant growth and development.

Other legumes such as alfalfa, clover, and peas also have nitrogen-fixing capabilities, but soybeans are particularly noted in crop rotations for their high yield potential and the economic advantages they provide to farmers.