Abstract:A mutant strain of Pseudomonas aeruginosa ZB27 resistant to chloramphenicol was obtained using the antibiotic label method.The colonization ability and control effect were determined with the spray and diluting plate methods. The result indicated that the concentration of labeled strain ZB27 resistant to chloramphenicol was 750μg/mL with stable characterization and high recovery. The labeled strain ZB27 could colonize rapidly on the leaves and branches and maintain steady colonization amount in a considerably long time. The number of colonization with high-concentration (109, 107CFU/mL) were higher than that with the low-concentration. The colonization on the leaves was higher and had longer alive period, which reached the peak at 8thd and kept high level till 40thd. The colonization of pathogen to biocontrol bacteria had great effects on leaves but little on branches. The control effect of inoculation bacterial suspensions or secondary metabolites was significant higher than the other treatments with 70.07% or 68.05%, respectively, indicating that bacterial suspensions and secondary metabolites had good effects for controlling hybrid bamboo blight.