One of the freeliving, anaerobic nitrogen fixer is (a) Beijernickia (b) Rhodospirillum (c) Rhizobium (d) Azotobacter.
Option B Many free living bacteria and blue green algae are capable to fix atmospheric nitrogen Rhodospirillum is a free living photosynthetic anaerobic nitrogen fixing nonsulphur bacteria. It is capable of synthesizing its organic food in presence of light and in absence of O 2 by a process known as bacterial photosynthesis. Beijernickia and Azotobacter are free living but aerobic nitrogen fixing bacteria. Rhizobium is a symbiotic nitrogen fixing bacteria.
