Bacterial Blight of Mock Orange (Philadelphus spp.) Caused by Pseudomonas syringae. B. W. Kennedy, Professor, Department of Plant Pathology, University of Minnesota, St. Paul 55108. J. Froyd, Research Scientist, Eli Lilly & Company, Greenfield, IN 46140; and R. Bowden, Former Graduate Research Assistant, University of Minnesota.. Plant Dis. 68:916-917. . Copyright 1984 The American Phytopathological Society. DOI: 10.1094/PD-68-916.

A bacterial leaf and shoot blight occurs regularly on mock orange, a popular woody ornamental shrub in Minnesota. The disease is caused by two variants of Pseudomonas syringae that persist in field-grown plants and in planting stock stored from one season to the next. Considerable difference in susceptibility exists among eight cultivars of Philadelphus commonly grown in Minnesota. Species of Viburnum and Hydrangea, ornamental plants in the same subfamily, were resistant.

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