Question

why is nitrogen fertilizer not added in the soil which leguminous plant are grown​

Answer 1

Leguminous plants contain Rhizobium bacteria in their root nodules. These bacteria have the ability to convert atmospheric nitrogen into a plant-usable form of nitrogen. Hence, farmers need not add nitrogenous fertilisers in the fields where leguminous plants grow.

Answer 2

Answer:

Leguminous plants have special root nodules where nitrogen fixation takes place with the help of rhizobium bacteria. So, it doesn't need any further nitrogen, also the soil where these plants are grown ,get enriched by nitrogen. Hence, nitrogen fertilizer is not added in soil in which leguminous plants are grown