Screening of Novel Bacteriophage Infection in Pseudomonas putida Isolated From Potato Disease

Background: In recent decades bacteriophages have been used as treating agents against some pathogens. Also, bacteriophages could be considered as alternatives of antimicrobial agents in plant protection. Objectives: This study aimed to isolate a pathogen from potato (Solanum tubersom) tubers (Pseudomonas putida), and of its specific bacteriophage from soil and wastewater. Materials and Methods: Infected samples of soft rot potato tubers were collected from Flavarjan farms (Isfahan province, Iran) to isolate and identify P. putida by biochemical and molecular methods. Soil and wastewater samples were obtained locally to isolate the bacteriophage attributed to P. putida. Soil suspension was centrifuged and then filtrated by 0.2 micrometer Millipore filter. The wastewater was directly filtrated by 0.2 micrometer filter after centrifugation. After incubation of isolated bacteria together with phage contained solution, plaques were detected in nutrient agar. Subsequently, clearance of P. putida liquid culture incubated by added filtrated bacteriophage was observed. The structure and morphological characteristics of P. putida related bacteriophage was remarked by transmission electron microscopy (TEM). Results: Isolated strain sda2 was identified as Pseudomonas putida with related accession number HQ423667. The result showed that isolated bacteriophage belonged to Cystoviridae family. Conclusions: We isolated a new strain of P. putida as well as a novel bacteriophage through which potato disease caused by the bacterium could be treated.