Question

Azolla is used as a biofertilizer because

• A. Azolla multiplies very fast to produce massive biomass.
• B. Azolla has association of mycorrhiza.
• C. Azolla has association of nitrogen-fixing Rhizobium.
• D. Azolla has association of nitrogen fixing cyanobacteria.

Answer 1

Answer: (D)

Azolla is used as biofertilizer as it is known to contribute 40-60 kg N/ha per crop. Azolla, contain symbiotic cyanobacteria, that provide some of their nitrogen directly from the atmosphere. In Azolla the cyanobacteria are directly transmitted to the next generation during the plant's reproductive cycle, so that the two organisms have co-evolved together for million of years, resulting in a superorganism, that is incredibly efficient.

So, the correct answer is option C.