Question

2. Leguminous plants do not require nitrogenous fertilizers. Give reason.

Answer 1

Leguminous plants have bacteria Rhizobium in their roots.Rhizobium can fix atmospheric nitrogen into soluble nitrates and nitrites required by the plant.Hence, leguminous plants do not need nitrogenous fertilizers.

Answer 2

Leguminous plants do not require external nitrogenous fertilizers as they receive their nitrogen from "nitrogen fixing bacteria" through symbiosis. Nitrogen is used to produce proteins and nucleic acids and is necessary for the plant.

Bacterial species such as Rhizobium form an association with the leguminous plants such as Pisum sativum (garden pea), by entering their roots and multiplying to form structures called nodules. These nodules help in nitrogen fixation by converting "atmospheric nitrogen into ammonia", in return the bacteria depend on the plant body for shelter.