Consider the following:
1. Rhizobium
2. Azotobacter
3. Mycorrhiza
4. Azolla
Which among the above are Biofertilizers?

Answer: [D] 1, 2, 3 & 4

Rhizobium, Azotobacter, Azospirillum, Phosphate Solubilizing Bacteria and mycorrhiza; these are the biofertilizers incorporated in India’s  Fertilizer Control Order (FCO), 1985.  Azolla, Rhizobium, Azotobacter, Azospirillum and blue green algae(BGA) have been traditionally used as Biofertilizers.  Blue  green algae such as Nostoc, Anabaena, Tolypothrix and Aulosira fix atmospheric nitrogen and are used as inoculants for paddy crop.  Azolla or mosquito fern has been used as a companion crop for paddy for at least a millennium.

This question is a part of GKToday's Integrated IAS General Studies Module