Pseudomonas fluorescens Pseudomonas fluorescent bacteria are the scientific name Pseudomonadaceae from the family living in the runaways of plants. Since runaway is the first defense bridge root against soil pathogens, these microorganisms and root colonizing rhizobacteria play a prominent role in this region. The advantages of these bacteria include increased germination rate, root growth and biocontrol of pathogenic agents. The characteristics of these bacteria are influenced by the environmental factors and host plants, and therefore finding suitable strains of this bacterium that can be well controlled against pathogens is valuable. Therefore, this study was conducted to determine the frequency of populations of Pseudomonas fluorescent bacteria in the soil samples of different host plants in some fields of Bushehr province.