Key words: Azotobacter
vinelandii, mutated strain, hyper-production of alginate.
A diverse array of bacteria including species of Rhizobium, Pseudomonas, Azospirillum, Azotobacter
, Bacillus, Burkholderia, Klebsiella, Enterobacter, Xanthomonas, Serratia and many others have been shown to promote plant growth (Vessey, 2003; Bashan et al., 2004).
Nine bacterial strains were used: Azospirillum brasilense (C16 and SP7), Azospirillum lipoferum C15, Azotobacter
chroococcum AC1 and AC10, Azotobacter
vinelandii AV5, Bradyrhizobium japonicum USDA110, Rhizobium sp.
It has been reported that inoculation with auxin-releasing Azotobacter
strains increases growth, yield, and nitrogen uptake in wheat and maize and that the combined application of Azotobacter
and tryptophan, which is often implicated in IAA synthesis, enhances plant growth in a greater extent [5, 9, 10].
The predominant bacterial genera identified were Bacillus, Pseudomonas, Desulfotomaculum, Desulfovibrio, Desulfomonas, Methylococcus, Vibrio, Micrococcus, Klebsiella and Azotobacter
, free living nitrogen fixing bacteria is considered as economical, low cost bio-fertilizer in agricultural productions.
The bacteria were Bacillus subtilis, Pseudomonas putida, Pseudomonas fluorescens, Azotobacter
beijerinckii, Micrococcus luteus, Bacillus pumilus, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus brevis, Streptococcus salivarius, Bacillus megaterium and Staphylococcus saprophyticus.
development is usually found in chernozems in the spring, during the wet season; while is hardly found in dryland soil (Karaguyshieva and Illyaletdinov, 1957).