Isolation of a photosynthetic microbial consortium formed mainly by cyanobacteria with capacity to fix nitrogen

The aim of this work was to isolate a photosynthetic Microbial Consortium (MC) with capacity to fix nitrogen, from biological material collected in a rice field. The isolated MC was maintained at BG–11₀ medium, free of nitrogen source and progressively scaled up at 0.5 L, 1 L, 1.9 L and 11 L working volume. The nitrogen fixing rates obtained in the 11 L reactor were three times higher to the reported by other nitrogen fixing cultures at laboratory scale, so it is recommended the MC application isolated at this investigation as biofertilizer for rice crops.

Keywords: biofertilizers, cyanobacteria, photosynthetic microbial consortium, biological nitrogen fixation, rice crops, fertilizers