Interaction between the biogeochemical cycles of C, N and P in the rhizosphere of nodulated legumes (bean model) in reference agro-ecosystems of the Mediterranean basin

To test the MOMOS model for the common bean (Phaseolus vulgaris) in the spatial variability of bean nodulation in the Sétif agro-écosytem where 6 contrasting sites have been identified ; Isolate rhizobia and rhizobacterias from nodulated roots of legumes in identified sites with high nodulation and low differences between contrsating genotypes in order to verify in controled environment whether thees bacteria could contribute to cempensate the low efficiency of the host to use P for nitrogen fixation. The finalized objective would be the selection of legume – bactéria associations with potential to fix nitrogen with limited P supplies.