Methods employed in the study of the fluorescent culture filtrates of Azotobacter are described. The use of a fluorescence meter in the characterization of the fluorescent substances elaborated by Azotobacter agile, Azotobacter vinelandii, and Azotobacter macrocytogenes n. sp. is discussed. A. macrocytogenes, a fluorescent species, is included with the two previously reported fluorescent Azotob...

Ten Azotobacter cultures were isolated from the maize rhizosphere and their auxin producing ability was measured colourimetrically. The auxin production by three efficient Azotobacter cultures (Z1, Z3, Z4) was also measured in the presence of filter sterilized L-tryptophan (at 10G, 10G and 10G M). Azotobacter culture Z4 gave relatively higher auxin production and was selected for further experi...

Azotobacter strains were isolated by serial dilution method and colonies were viscous, smooth, glistening, and brown to black colour on Jenson's N-free agar. Morphological and biochemical tests showed characteristic features of Azotobacter. Further, molecular analyses revealed the presence of different Azotobacter species viz., A. armeniacus, A. chroococcum, A. salinestris, A. tropicalis and A....

The objectives of this study were to count and culture Azotobacter spp. in sampled soils, to determine the nitrogen (N) fixing capacity byAzotobacter spp. in pure culture and different soils, and to explore the relationships between N fixation capacity of Azotobacter spp. and microbiological properties of soils in Northern Anatolia, Turkey. Statistically significant relationships were found bet...

L6hnis and Smith (1923) pointed out that not less than seven different morphological types can be developed and stabilized from Azotobacter cultures. This extreme transmutation of cells has been questioned by subsequent investigators (Lewis, 1937, 1941). Nevertheless, peculiar morphological phases do occur in Azotobacter cultures and no satisfactory explanation has been given as to their functi...

Four laboratory strains and two isolates of Azotobacter vinelandii were found to contain plasmids. Twenty-five laboratory strains which could fix nitrogen did not have free, covalently closed circular plasmid DNA. The plasmids varied in size from 9 to 52 megadaltons, and each strain yielded only one plasmid. No discernible differences in ability to fix nitrogen were found between plasmid-bearin...

A new type of ferredoxin was isolated from Azotobacter vinelandii cells. The protein was able to replace the native chloroplast ferredoxin in the photoreduction of nicotinamide adenine dinucleotide phosphate (NADP) and functioned as a reductant for the Azotobacter nitrogenase.

Nitrogen fixation is mainly responsible for improvement of crop yield. In this regard, diazotrophs like Rhizobium, Azotobacter and Azospirillum are important as they enrich nitrogen nutrition in N-deficient soils. Of these, Azotobacter promotes plant growth as well as nitrogen fixation. Thus technology has been developed for making use of Azotobacter biofertilizer for nitrogen and non-nitrogen ...