6. Mr. Aasfar Abderrahim

Due to their ability to convert atmospheric N2 into plant-usable ammonia, nitrogen-fixing rhizobacteria should be explored as a sustainable alternative to chemical nitrogen fertilizers for several economically important crops. In this work, nitrogen-fixing strains were isolated and screened from several rhizospheric soils of Morocco, 23 nif-H+ strains belonging to Bacillus sp, pseudomonas sp, Arthrobacter sp, Burkholderia sp and yeasts were selected to evaluate their PGPR traits. The results showed that almost all selected strains have significant abilities in atmospheric nitrogen fixation, phosphate solubilization, phytohormone production and their effects on plant growth parameters under controlled conditions. Then, 3 strains were selected to evaluate their ability to reduce chemical nitrogen supply and to evaluate their behavior in combination with TSP fertilizer and rock phosphate as two sources of phosphate. The yeast strain AZ-516, Arthrobacter sp. and Pseudomonas sp used individually or in combination have been shown to reduce nitrogen fertilization by up to 50% without impacting wheat plant yields.