Antagonistic effect of Endophytic bacteria against Erwinia amylovora

Background and Aim : Recently, potential role of endophytic bacteria in control of phytopathogens has been demonstrated. In our country, Iran, few studies has been done about the role of these bacteria in controlling plant bacterial pathogens. Therefore, the aim of this study was to isolate and identify endophytic bacteria with antagonistic activity against Erwinia amylovora.Methods : Soil, root and leaf samples of apple and pear trees were collected from gardens located in vicinity of Gorgan, Golestan, Iran. The samples were disinfected by ethanol and sodium hypochlorite, rinsed three times with sterile distilled water (SDW). After cutting roots and leaves into small fragments in SDW, a loopful of the resulting suspension was streaked on nutrient agar and incubated at ۲۶°C for ۳ days. All colonies were distinguished based on their morphology and purified. Finally, the ability of the isolates to produce diffusible metabolites was tested according to the agar well diffusion assay.Results : Bacterial strains isolated from the samples were identified as follow: Bacillus spp., Brevibacillus spp., Paenibacillus spp. The inhibitory effect of these isolates was evaluated against E. amylovora and revealed that Bacillus spp. were able to inhibit E. amylovora growth in agar well diffusion assay.Conclusion : Based on the result of this study, Bacillus spp. are promising organisms for the control of plant diseases caused by Erwinia amylovora. However, further studies required to determine accurately the biochemical and molecular characteristics used to distinguish a given species and their potential application in biological control.

کلیدواژه ها:

Antagonistic effect ، Erwinia amylovora ، Endophyte ، Soil ، Leaves ، Root