Question

Rhizobium is found in

• A. Maize root.
• B. Gram root.
• C. Branch of a plant.
• D. Sugarcane root.

Answer 1

Answer: (B)

Gram root.

Rhizobium is the bacterium which fixes nitrogen in symbiotic association with roots of leguminous plants. Gram is one of the examples of the dicot legume plant. Initially, the bacteria grow in soil near the roots of higher plants where they fail to fix the nitrogen. These bacteria when coming in contact with leguminous plants, interact chemically and enter into roots through root hairs, and fix nitrogen with the help of the enzyme nitrogenase.

Thus, the correct answer is option B.