Influence of Phosphate Dissolving Bacteria on the Efficiency of Superphosphate in a Calcareous Soil Cultivated with Vicia faba

In a pot experiment with Vicia faba grown in a calcareous soil and fertilized with three rates on superphosphate, inoculation with phosphate dissolving bacteria (PDB) increased P‐uptake and dry weight. The effect of inoculation exceeded that of the fertilization with half of the usual rate. Dry weight and P‐uptake of plants grown in inoculated soils receiving one half of the usual rate of superphosphate were higher than those for plants grown in pots receiving the usual rate of superphosphate in the absence of the inoculation. The usual rate of superphosphate in the presence of inoculation doubled both P‐uptake and dry weight of Vicia faba. However, one half of the usual rate of superphosphate in the presence of inoculation with PDB increased P‐uptake and dry weight of faba plants by one half more than the control.