Question

Which of the following is a symbiotic nitrogen fixer ?

• A. Frankia
• B. Azolla
• C. Glomus
• D. Azotobacter

Answer 1

Answer: (C)

Symbiotic nitrogen fixation is part of a mutualistic relationship in which plants provide a niche and fixed carbon to bacteria in exchange for fixed nitrogen. Glomus is a genus of arbuscular mycorrhizal (AM) fungi, and all species form symbiotic relationships (mycorrhizas) with plant roots. All species of Glomus are symbiotic nitrogen fixers.

Thus the correct answer is option B.