Class 12th Biology 2017 Set2 Delhi Board Paper Solution
Question 8
How does the application of cyanobacteria help to improve agricultural output?
Answer
Cyanobacteria are autotrophic microbes widely distributed in aquatic and terrestrial environments. Most of these can fix atmospheric nitrogen, e.g. Anabaena, Nostoc, Oscillatoria, etc. In paddy fields, cyanobacteria serve as important biofertiliser. Blue green algae also add organic matter to the soil, thus increasing the fertility. Thus, application of cyanobacteria helps in improving agricultural output.
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