Alginate-perlite encapsulated Pseudomonas putida A (ATCC 12633) cells: preparation, characterization and potential use as plant inoculants.

•Immobilization of Pseudomonas putida in Ca-alginate-perlite microbeads.•Progressive release of cells into the medium for microbeads containing 0.4% perlite.•High colonization of A. thaliana rhizosphere using Ca-alginate-perlite microbeads.•Advantage of the immobilized system over free P. putida cells to promote growth of A. thaliana.