The effect of the microalgae-growth promoting bacterium Azospirillum brasilense on accumulation of total carbohydrates and starch in two species of Chlorella (Chlorella vulgaris and Chlorella sorokiniana), when the bacterium and each microalga were jointly immobilized in alginate beads was studied under autotrophic conditions for 144 h in synthetic medium. The interaction of the bacterium with ...

this study in order to evaluate the possibility of improving the root growth of lentil with use mycorrhiza symbiosis with cooperation azospirillum bacteria under rainfed conditions was conducted. a tri-factorial experiment was organized on the basis of randomized complete block design with four replicates, in which factor m was the mycorrhizal inoculums in three levels including (not use, use m...

Azospirillum lipoferum 4T has original properties such as nonmotility, melanin synthesis, and laccase activity. Following random Tn5 mutagenesis in A. lipoferum 4T, we obtained 10 mutants which were affected in melanization and laccase activity. The class 1 mutants, with intermediate levels of laccase activity, showed some coloration; the class 2 mutants, which were completely negative for lacc...

Mixed cultures of Cellulomonas sp. and Azospirillum brasilense were grown with straw or cellulose as the carbon source under conditions favoring the fixation of atmospheric nitrogen. Rapid increases in cell numbers, up to 10 cells per g of substrate, were evident after 4 and 5 days of incubation at 30 degrees C for cellulose and straw, respectively. Nitrogen fixation (detected by acetylene redu...

HIGHLIGHTS Azospirillum brasilense stimulates root growth in maize under water deficit. Maize inoculated with A. shows greater photosynthesis drought conditions. Under deficit, plants showed use efficiency (WUE).

A lepidopteran toxin gene, cryIC (pSB607) from entomopathogenic Bacillus thuringiensis subsp. aizawai was introduced into nitrogen-fixing Azospirillum lipoferum by transformation. Regeneration of spheroplasts was achieved at 99% with 39% frequency of regeneration. Transformants were screened on NB kanamycin with ampicillin plates and 4 transformants were selected after ten generations. SDS-PAGE...

Azospirillum brasilense Sp7 and its ntrA (rpoN), ntrBC, and ntrC mutants have been evaluated for their capabilities of poly-3-hydroxybutyrate (PHB) accumulation in media with high and low ammonia concentrations. It was observed that the ntrBC and ntrC mutants can produce PHB in both low- and high-C/N-ratio media, while no significant PHB production was observed for the wild type or the ntrA mut...

Azospirillum brasilense is a nitrogen fixing bacterium that has been shown to have various beneficial effects on plant growth and yield. Under normal conditions A. brasilense exists in a motile flagellated form, which, under starvation or stress conditions, can undergo differentiation into an encapsulated, cyst-like form. Quantitative RT-PCR can be used to analyse changes in gene expression dur...

Pot greenhouse experiments were carried out to attempt to increase the salinity tolerance of one of the most popular legume of the world; cowpea; by using dual inoculation of an Am fungus Glomus clarum and a nitrogen-fixer Azospirillum brasilense. The effect of these beneficial microbes, as single- or dual inoculation-treatments, was assessed in sterilized loamy sand soil at five NaCl levels (0...

The microaerophilic nitrogen-fixing bacterium Azospirillum brasilense formed a sharply defined band in a spatial gradient of oxygen. As a result of aerotaxis, the bacteria were attracted to a specific low concentration of oxygen (3 to 5 microM). Bacteria swimming away from the aerotactic band were repelled by the higher or lower concentration of oxygen that they encountered and returned to the ...