Résumé:
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.
