ROOT COLONIZATION CAPACITY BY PLANT BENEFICIAL BACTERIA

Abstract

An important characteristic of a microorganism in order to be suitable as a biocontrol agent is to be an efficient rhizosphere colonizer. Plant root colonization is the major step which initiates different and complex interactions between plants and surrounding soil microorganisms. In this study, we tested the capacity of different bacterial strains (Bacillus licheniformis B40, Bacillus amyloliquefaciens Bw, Bacillus sp. Bw1and Pseudomonas aeruginosa P14) to colonize plant root and seed coat. Scanning electron microscopy was employed to analyze cucumber Cucumis sativus L. seed tegument and roots colonized by these strains. The results showed an abundant colonization of seed coat by three of the bacterial strains used, but only Pseudomonas aeruginosa P14 strain managed to colonize more efficiently the cucumber roots.