Rhizoplane colonization under gnotobiotic (aec) or non sterile conditions (def) of a beneficial bacteria, Burkholderia phytofirmans strain PsJN, tagged with gfp showing (a and
d) single bacterial cells attached to the root surfaces of grapevine, (b and e) lines of bacteria or (c and f) bacteria colonizing the whole outline of some rhizodermal cells. Scale bars:
(a) 15 mm, (bed) 30 mm, (e) 15 mm and (f) 40 mm. Pictures by S. Compant.