Question

Ravi wanted to grow rice in his field. He was very concerned about environmental degradation, so he did not want to use chemical fertilisers. Suggest a suitable biological method to Ravi.

Answer 1

He should use biofertilisers such as cyanobacteria (Anabaena, Nostoc, Aulosira), nitrogen-fixing bacteria like Azospirillum, or Azolla (a fern that harbours Anabaena) to enrich the soil without using chemical fertilisers.