Question
Anabaena as a biofertilizer
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Answer
- Anabaena is a cyanobacterial biofertilizer.
- It is multicellular, filamentous nitrogen fixing organism that exits as plankton.
- It can fix nitrogen both in free living conditions as well as by forming symbiotic associations.
- Anabaena forms symbiotic relationship with Azolla, Anthoceros and Cycas.
- It is found in dorsal leaf lobe in Azolla, thallus of Anthoceros and in coralloid roots of Cycas.
- It has specialized colourless cells known as heterocysts.
- Heterocysts are the sites for nitrogen fixation.
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