Bacterial Brown Spot of Wild Rice. R. L. Bowden, Former Research Assistant, Department of Plant Pathology, University of Minnesota, St. Paul 55108. J. A. Percich, Assistant Professor, Department of Plant Pathology, University of Minnesota, St. Paul 55108. Plant Dis. 67:941-943. Accepted for publication 11 March 1983. Copyright 1983 American Phytopathological Society. DOI: 10.1094/PD-67-941.

Bacterial brown spot (BBS) of wild rice (Zizania aquatica) is characterized by elliptical to spindle-shaped lesions 2–12 mm long and 1–10 mm wide, which may become irregularly shaped or diffuse with lengths exceeding 100 mm. Three strains from BBS lesions were pathogenic to wild rice but not corn, wheat, or barley. Nine strains from BBS lesions were identified as Pseudomonas syringae pv. syringae and were distinguished from 11 strains of pv. zizaniae from bacterial leaf streak of wild rice by utilization of trigonelline and l(+) lactate and by production of syringomycin but not tyrosinase.