VIEW ARTICLE

Ornamental Plants as Carriers of Pseudomonas aeruginosa. J. J. Cho, Former Research Assistant, Department of Plant Pathology, University of California, Berkeley 94720, Present address of senior author: Hawaiian Agricultural Experiment Station, Kula, Hawaii 96790; M. N. Schroth(2), S. D. Kominos(3), and S. K. Green(4). (2)Professor, Department of Plant Pathology, University of California, Berkeley 94720; (3)Clinical Microbiologist, Mercy Hospital, Pittsburgh, Pennsylvania 15219; (4)Former Graduate Student, Department of Plant Pathology, University of California, Berkeley. Phytopathology 65:425-431. Accepted for publication 1 November 1974. DOI: 10.1094/Phyto-65-425.

Pseudomonas aeruginosa was isolated from foliage and soil of healthy potted ornamental plants, including African violet, azalea, chrysanthemum, hydrangea, and petunia. These plants were obtained from propagation houses, nurseries, and retail outlets. With chrysanthemums, populations of P. aeruginosa were as high as 50 cells/leaf and 5 × 10⁵ cells/g of soil. Sixty-one percent of the isolates from the foliage and 5% of the isolates from the soil were identified as distinct pyocin types. The principal types, B-7, F-6, and F-2, belong to the major groups of clinical strains which cause hospital-associated infections in humans. Although potted ornamental plants present another potential source for the introduction of P. aeruginosa into the hospital environment, its relative importance as a disseminating agent appears inconsequential compared to other sources. Many agricultural strains of P. aeruginosa and corresponding clinical pyocin types were capable of rotting lettuce, celery, and potatoes, but varied in virulence.