Which of the following is common to Azospirillum, Anabaena, Nostoc and Oscillatoria
$N_{2}$-fixer microbes
Prokaryotic organism
Both $(a)$ and $(b)$
Eukaryotic organism
Azotobacter and Bacillus polymyxa are
Which of the following is not a symbiotic nitrogen fixing bacterium?
Symbiotic nitrogen fixation in root nodules of some legumes is caused by
Farmers have reported $50\%$ higher yield of rice by using biofertilizer
Agricultural chemicals include