Is Azotobacter a free-living nitrogen-fixing bacteria?

Azotobacter spp. are Gram negative, free-living, aerobic soil dwelling,1 oval or spherical bacteria that form thick-walled cysts (means of asexual reproduction under favorable condition). A chroococcum is the first aerobic free-living nitrogen fixer.

Is Azotobacter a free-living bacteria?

Azotobacter vinelandii is a free-living N2-fixing bacterium that has been shown to degrade phenolic compounds and use them as a carbon and energy source.

What type of bacteria can use free nitrogen?

Two kinds of nitrogen-fixing microorganisms are recognized: free-living (nonsymbiotic) bacteria, including the cyanobacteria (or blue-green algae) Anabaena and Nostoc and genera such as Azotobacter, Beijerinckia, and Clostridium; and mutualistic (symbiotic) bacteria such as Rhizobium, associated with leguminous plants.

Which medium used for the Azotobacter isolation?

Mannitol
Azotobacter Agar (Mannitol) is used for isolation and cultivation of mannitol positive Azotobacter species from soil (2). It is also useful for maintenance of Azotobacter species by adding extra 1% Mannitol to the medium as specified by the American Type Culture Collection (3).

What kind of bacteria fix nitrogen in the atmosphere?

Azotobacter species are free-living, nitrogen-fixing bacteria; in contrast to Rhizobium species, they normally fix molecular nitrogen from the atmosphere without symbiotic relations with plants, although some Azotobacter species are associated with plants.

What kind of nitrogen fixer is Azotobacter?

Azotobacter is a well-known nonsymbiotic nitrogen fixer. Although Azotobacter was described in 1901, the organism is attracting microbiologist attention for its interesting potential applications.

What kind of climate does Azotobacter bacteria live in?

The growth is favoured at a temperature of 20–30°C. Azotobacter species are free-living, nitrogen-fixing bacteria; in contrast to Rhizobium species, they normally fix molecular nitrogen from the atmosphere without symbiotic relations with plants, although some Azotobacter species are associated with plants.

Which is the most dominant non symbiotic nitrogen fixing bacterium?

There are different kinds of microorganism which could assimilate atmospheric nitrogen. They are symbionts like Rhizobiumor Mycorrhiza free living non symbiont like Azotobacter, Azospirillum, Azolla, Cyanobacteria etc. The most dominant non-symbiotic nitrogen-fixing heterotrophic bacterium in Indian soils is Azotobacter chroococcum.