Archivio Journal of Plant Pathology

Abstract:

Bacterial soft rot can be a destructive disease of ornamental plants. To identify the pathogenic soft rot bacteria occurring in ornamental plants in Tehran and Markazi provinces (Iran), 57 isolates were obtained from 12 different mono- and dicotyledonous hosts and investigated with regard to phenotypic, genotypic and pathogenicity features. Based on phenotypic characteristics, the bacterial strains were identified as Pectobacterium carotovorum subsp. carotovorum. This was confirmed by subspecies-specific primers using PCR. Inoculation of all isolates into Aglaonema leaves confirmed the pathogenecity of the isolated strains. To assess the genetic diversity within Pectobacterium carotovorum subsp. carotovorum populations by rep-PCR, 26 isolates were selected according to their host and geographic distribution as well as two strains from Guilan province. Cluster analysis was conducted using the UPGMA method and revealed a possible close relationship between DNA fingerprints and geographical origins of isolates. Our results showed significant genetic variation among the populations of this pathogen. To the best of our knowledge, this is the first report of Pectobacterium carotovorum subsp. carotovorum on Peperomia obtusifolia, P. caperata, Pilea cadierei, Plectranthus australis, Saintpaulia ionantha and Kalanchoe tubiflora in Iran.