Valorisation de quelques isolats du genre Bacillus comme agent de biofertilisation

Abstract

Rhizobacteria play an important role in maintaining the balance of the soil, among these bacteria there are those which have shown their ability to promote plant growth (PGPR), they act positively on the growth of the plant. The objective of our work is to isolate bacteria belonging to the genus Bacillus sp which has been identified as such, in order to demonstrate that it has the capacity to solubilize phosphate and fix nitrogen. The results revealed to characterize 60 bacterial isolates isolated from the rhizosphere and the soil rhizoplan (arid and semi-arid region), from the two sites in western Algeria (Mostaganem and Oran). The results obtained were used to select and classify the best performing Bacillus for solubilizing phosphate, the solubilization diameter of which varies between 0.1 ± 00ed up to 0.63 ± 03d. The OD62 strain is the best performing with a value of 0.63 ± 03j. It is concluded that the use of Bacillus sp as a biofertilizer to promote plant growth, fix nitrogen and solubilize phosphate may present an important biotechnological approach to reduce the problems associated with the use of chemical fertilizers.