Bacterial Barn Rot of Flue-Cured Tobacco in North Carolina. Harvey W. Spurr, Jr., Research Plant Pathologist, Southern Region, SEA/AR, USDA, Oxford Tobacco Research Laboratory, Oxford, NC 27565, and Professor of Plant Pathology, North Carolina State University, Raleigh. Eddie Echandi, Professor, B. C. Haning, Assistant Professor, and F. A. Todd, Philip Morris Extension Professor of Plant Pathology, North Carolina State University, Raleigh 27650. Plant Dis. 64:1020-1022. Copyright 1980 American Phytopathological Society. DOI: 10.1094/PD-64-1020.

Barn rot has become an important postharvest disease of flue-cured tobacco in North Carolina and the southeastern United States. This coincides with and may be related to an increase in the use of mechanized harvesters and bulk curing of leaf. Strains of Erwinia carotovora and E. chrysanthemi isolated from barn rotted leaves were pathogenic to tobacco. Reactions were significantly different among 20 tobacco cultivars representing eight tobacco types inoculated with a pathogenic strain of E. carotovora var. carotovora, but all cultivars were susceptible. Both commercial and noncommercial flue-cured tobacco seed were infested with numerous bacteria. Pectolytic positive bacteria infested 3–21% of the seed in the samples tested. Infested tobacco seed may be an important source of inoculum.