Question

A stem nodulating plant

• A. Glyricidia maculata
• B. Sesbania rostrata
• C. Pongamia pinnata
• D. Sesbania aculeata

Hint:

Remember: Sesbania rostrata is stem-nodulating, whereas the common Indian species Sesbania aculeata (Dhaincha) is solely root-nodulating.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Most nitrogen-fixing leguminous plants form symbiotic nodules exclusively on their roots. However, a few specialized species can also form functional nodules on their stems.

Step 2: Detailed Explanation:
Sesbania rostrata is a tropical leguminous green manure crop native to West Africa.
It is highly unique because it forms symbiotic nitrogen-fixing nodules on both its root system and its aerial stem.
This stem nodulation is initiated by infection with the bacterium Azorhizobium caulinodans.
This dual nodulation mechanism allows Sesbania rostrata to fix significantly more nitrogen per unit of land than traditional root-nodulated legumes.

Step 3: Final Answer:
Hence, Sesbania rostrata is the stem nodulating plant.