Alternatively, PSB can applied through fertigation or in hydroponic operations. Many different strains of these bacteria have been identified as PSB, including Pantoea agglomerans (P5), Microbacterium laevaniformans (P7) and Pseudomonas putida (P13) strains are highly efficient insoluble phosphate solubilizers. Recently, researchers at Colorado State University demonstrated that a consortia of four bacteria (sold commercially as Mammoth P) synergistically solubilize phosphorus at a much faster rate than any single strain alone