PCR amplification of the hrcV gene through specific primers for detecting Pseudomonas syringae pathovars.

Pseudomonas syringae pathovars are important pathogens among phytopathogenic bacteria causing a variety of diseases in plants. These pathogens can rapidly disseminate in a large area leading to infection and destruction of plants. To prevent the incidence of the bacteria, appropriate detection methods should be employed. Routinely serological tests, being time-consuming and costly, are exploited to detect these pathogens in plants, soil, water and other resources. Over the recent years, DNA-based detection approaches which are stable, rapid, specific and reliable have been developed and sequence analysis of various genes are widely utilized to identify different strains of P. syringe. However, the greatest limitation of these genes is inability to detect numerous pathovars of P. syringae. Herein, by using bioinformatic analysis, we found the hrcV gene located at pathogenicity islands of bacterial genome with the potential of being used as a new marker for phylogenetic detection of numerous pathovars of P. syringae. Following design of specific primers to hrcV, we amplified a 440 bp fragment. Of 13 assayed pathovars, 11 were detected. Also, through experimental procedures and bioinformatic analysis it was revealed that the designed primers have the capacity to detect 19 pathovars. Our findings suggest that hrcV could be used as a gene with the merit of detecting more pathovars of P. syringae in comparison with other genes used frequently for detection purposes.