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Microbes in Human Welfare — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMicrobes in Human Welfare1 Mark
MCQ
Azolla is used as a biofertilizer, because it:
  • A
    Multiplies very fast to produce massive biomass
  • B
    Has association of nitrogen-fixing Rhizobium
  • C
    Has association of nitrogen-fixing Cyanobacteria
  • D
    Has association of Mycorrhiza
✓

Answer

  1. Has association of nitrogen-fixing Cyanobacteria

Explanation:

Azolla can be used as a biofertilizer as cyanobacteria. Cyanobacteria live in symbiotic association with the roots. As a result, Azolla-Anabaena can fix almost three times more atmospheric nitrogen than legumes. Typical rates for legumes are 400 kg of nitrogen per hectare per year those for Azolla-Anabaena are 1100 kg of nitrogen per hectare per year.

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