Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: August 4, 2004
Publication Date: June 1, 2004
Citation: Medrano, E.G., Jones, M., Bell, A.A. 2004. Association of Pantoea agglomerans with seed rot of South Carolina cotton [abstract]. Phytopathology. 94:S69. Technical Abstract: In recent years, seed rot of cotton has occurred extensively in southeastern states causing considerable yield losses particularly in South Carolina. The causative agent(s) of the disease syndrome has not been identified. Symptoms of infected fruits include stunted fiber development and macerated locules. Microorganisms were isolated on TSA plates from seeds that were excised from diseased bolls. Presumptive P. agglomerans isolates were recovered from 10 of 20 bolls tested based on colony morphology, Gram staining, and carbon utilization testing. Two randomly selected isolates were marked with resistance to rifampicin (Rif) by incremental exposure to the antibiotic up to 200 micrograms / ml. Pathogenicity testing was conducted by injecting the Rif resistant isolates into healthy cotton bolls. Rifampicin resistant mutants were recovered from diseased fruits harvested two weeks post inoculation whereas, mock inoculated controls demonstrated no disease symptoms. Thus, P. agglomerans was determined to be capable of producing symptoms analogous to those of the seed rot of cotton observed in South Carolina.