Beneficial traits of root endophytes and rhizobacteria associated with plants growing in phytomanaged soils with mixed trace metal-polycyclic aromatic hydrocarbon contamination

The diversity of cultivable bacteria associated with plants from phytomanaged soils mixed trace metal (TM) and polycyclic aromatic hydrocarbon (PAH) contamination in Pierrelaye (France) was evaluated. emphasis on the bacterial community since overall objective is to obtain inoculants improve remediation this type contaminated site. Root endophytic rhizosphere soil counts were determined, isolates pooled by amplified rDNA restriction analysis identified 16S sequencing. Isolates further characterized for production plant growth-promoting (PGP) substances, resistance TM. selected strains evaluated their ability degrade PAHs. potential cell-free microbial supernatant increase mobilisation PAHs polluted also Proteobacteria Actinobacteria dominated collection isolates, differences taxonomic observed between species (Populus or Zea mays) depending treatment inoculation mycorrhizae Populus intercropping Alnus). majority exhibited at least one tested PGP traits, as well more than Several rhizosphere, endophyte even bulk isolate showed high rates fluoranthene pyrene reduction. Rhizobium strain MR28 isolated maize degrading produced bioemulsifying molecules capable improving availability Pierrelaye. A selection most interesting made re-inoculation experiments order assess rhizoremediation processes.