Inoculation with Phosphate Solubilizing Mesorhizobium Strains Improves the Performance of Chickpea (Cicer aritenium L.) Under Phosphorus Deficiency

The use of phosphate-solubilising bacteria as inoculants increases plant phosphorus (P) uptake and thus crop yield. Strains from the genus Mesorhizobium are among the most powerful phosphate solubilizing microorganisms. In order to study efficiency in P uptake and N2 fixation in chickpea (Cicer aritenium), forty-two rhizobia strains natively from Tunisian soils were studied in symbiosis with the chickpea variety “Beja1” which is frequently cultivated in Tunisia. Plants were inoculated separately with these strains under controlled conditions in perlite under two sources of P i.e. soluble (KH2PO4) and insoluble P (Ca2HPO4). At flowering stage, growth, nodulation, P uptake and N2 fixation were assessed in all symbiotic combinations. The results showed that the S27 strain efficiently mobilized P into plants, observed as a significant increase of plant P content when insoluble P (Ca2HPO4) was supplied to the soil. This was associated with a significant increase in plant biomass, nodule number and N content un...