The common nitrogenfixer in paddy fields is
Rhizobium
Azospirillum
Oscillatoria
Frankia.
$VAM $ is important for
Some blue green algae can be used as biofertilizer as they are
Organic farming includes
$I.$ use of biofertilisers and biopesticides
$II.$ crop rotation
$III.$ locally developed pest resistant varieties
Choose the correct option
Aquatic fern which is an excellent biofertilizer
The main sources of biofertilisers are