Rapid Identification of Xanthomonas campestris pv. campestris by ELISA. A. M. Alvarez, Associate Professor, Department of Plant Pathology, University of Hawaii, Honolulu 96822. K. Lou, Assistant Researcher, Department of Plant Pathology, University of Hawaii, Honolulu 96822. Plant Dis. 69:1082-1086. Accepted for publication 3 June 1985. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/PD-69-1082.

A double-antibody sandwich (DAS)-ELISA was developed to detect Xanthomonas campestris pv. campestris in leaf disks sampled from cabbage in the field. Assay time was reduced from 3–5 days with semiselective media to 5 hr with DAS-ELISA. Sheep and rabbit antisera were used as primary and secondary antibodies. Goat antirabbit peroxidase and purified 5-aminosalicylic acid were used as the enzyme indicator system, measured at 450 nm. On the basis of 510 samples with a disease incidence of 56%, 96.8% of known positives were detected by DAS-ELISA as confirmed by isolation and pathogenicity tests. DAS-ELISA permitted the processing of large numbers of samples and facilitated identification of the pathogen in seedbeds, on weeds, and on cabbage plants that showed unusual symptoms.

Keyword(s): black rot.