A distinct pathotype of Ralstonia (Pseudomonas) solanacearum race 1, biovar 1 entering Florida in pothos (Epipremnum aureum) cuttings

Ralstonia solanacearum was isolated from diseased pothos (Epipremnum aureum ) cuttings imported to Florida from Costa Pica. Epipremnum aureum has not p reviously been described as a host of R. solanacearum. Bacterial isolates w ere identified by standard bacteriological tests, FAME analysis (MIDI (R)), metabolic profile (Biolog (R)), and by PCP using species-specific primers. All isolates were biovar 1, Gram-negative, oxidase negative, catalase posi tive, motile,strictly aerobic, and accumulated poly-beta-hydroxybutyrate. S imilarity indices using MIDI matched in most cases to R. solanacearum; howe ver, low similarity indices were obtained with the Biolog data base. PCP am plification and electrophoretic analysis revealed a 148 bp product for all pothos isolates, identical to that in R. solanacearum control strains. Path ogenicity of isolates from pothos were compared with tomato and potato isol ates from Florida on tomato, potato, pothos, tobacco; and triploid banana. Isolates from pothos caused wilt of tomato and potato, variable symptoms on tobacco, and mild symptoms on banana; they were identified as race 1. Rals tonia solanacearum isolates from pothos represent a distinct pathotype of r ace 1, biovar 1 and differ from other race 1, biovar 1 strains by being pat hogenic on pothos.