Use of Xanthomonas campestris pv. vesicatoria to Evaluate Surface Disinfectants for Canker Quarantine Treatment of Citrus Fruit. G. Eldon Brown, Scientific Research Department, Florida Department of Citrus, Lake Alfred 33850. T. S. Schubert, Florida Division of Plant Industry, Gainesville 32602. Plant Dis. 71:319-323. Accepted for publication 31 October 1986. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1987. DOI: 10.1094/PD-71-0319.

Florida citrus packinghouses are required by quarantine regulations to use chlorine or sodium orthophenylphenate (SOPP) to surface-sanitize asymptomatic fruit to eradicate a bacterial disease currently classified as citrus canker (Xanthomonas campestris pv. citri). Treatments with chlorine or SOPP in soak or spray applications require exposures for 2 and 1 min, respectively, whereas soap formulations of SOPP applied during washing require 45 sec. In this study, applications of chlorine or SOPP during washing for 30 sec were as effective as the longer exposures currently required. Wash applications of dual quaternary ammonium compounds, formulations of chlorine dioxide, or peracetic acid for a similar time were equally effective. X. campestris pv. vesicatoria was used in these studies as the assay bacterium because it responded similarly to the canker bacterium in in vitro disinfectant tests and could be used outside of quarantine facilities.

Keyword(s): Citrus sinensis, postharvest pathology.