VIEW ARTICLE

Physiology and Biochemistry

Hypersensitivity of Suspension-Cultured Tobacco Cells to Pathogenic Bacteria. Merelee M. Atkinson, Department of Plant Pathology, North Carolina State University, Raleigh 27695-7616, Present address: USDA-ARS Plant Pathology Laboratory, Bldg. 004, Rm. 201, Beltsville, MD 20705; Jeng-sheng Huang(2), and James A. Knopp(3). (2)Department of Plant Pathology, North Carolina State University, Raleigh 27695-7616; (3)Department of Biochemistry, North Carolina State University, Raleigh 27695-7616. Phytopathology 75:1270-1274. Accepted for publication 23 July 1985. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/Phyto-75-1270.

The hypersensitive reaction of suspension-cultured tobacco cells to pathogenic bacteria was investigated. Net electrolyte efflux, an initial stimulation and subsequent decline in respiration rate, the development of brown pigmentation, and finally cell death were observed in tobacco cells after inoculation with Pseudomonas syringae pv. pisi (incompatible with tobacco) or avirulent isolate B1 of P. solanacearum strain K60. The specificity of the reaction was tested by measuring electrolyte efflux and cell death induced by P. solanacearum K60 and Agrobacterium tumefaciens (both compatible with tobacco), P. fluorescens (a saprophyte), and cells of heat-killed P. s. pv. pisi. With the exception of P. solanacearum K60, these bacteria induced little electrolyte loss and did not kill tobacco cells. These results demonstrate that the hypersensitive reaction of suspension-cultured tobacco cells is similar to that of tobacco leaf tissue with respect to symptom development and specificity of induction. Suspension-cultured tobacco cells thus provide a model system for further studies of hypersensitivity.