Isolement et caractérisation du potentiel PGP des PSB rhizosphèrique

Abstract

The PSBs plays a very important role in the growth and development of plants, their action is necessary for the availability of P, which increases and improves the plant productivity, as long as they are common in the rhizosphere. They are part of the PGPR (Plant growth promoting rhizobacteria), their PGP activity shows a beneficial interest for agriculture, because of the promotion of certain character in the rhizosphere. Through our work we isolated phosphate solubilizing bacteria, from the 3 compartments of the rhizosphere of 4 soil samples from the region of Douar Shaibia of the Wilaya of Mostaganem by selecting the isolates having presented a clear halo around the colonies, and making identification test which showed us that the majority of the isolates are Gram-, Bacillus form, and of different color and consistency, and of strict Aerobic respiratory type for the majority IV of the isolates, The analysis of the results obtained, from the PGP activity tests showed us that our isolates have the capacity to produce IAA with a maximum production of 12.33a±0.3, and all isolates were able to fix nitrogen. 11% of the isolates have the ability to produce HCN and for zinc solubilization we scored the highest solubilization rate with a value of 699.66g±35.1 in isolate VAY12. The phosphate solubilization of these isolates allowed to mark a quantity of phosphate up to 349k, 33 for isolate VAY110, and minimal solubilization 188,66f±32,1, in isolate VCZ8.