Diagnosis of Bacterial Infections by Immunological Methods

Abstract

Plant diseases caused by bacteria may be difficult to diagnose. Correct diagnosis often cannot be made on the presence of symptoms alone, since similar pathological conditions may be caused by quite different bacterial pathogens. Thus, isolation and subsequent identification of the bacteria by means of different biochemical tests and inoculation of plants may be necessary to fulfil the requirements of Koch’s postulates. Such methods may be rather time-consuming, and in an effort to simplify and speed up the detection and identification of phytopathogenic bacteria, the use of different immunological methods have come into widespread use. For many years traditional techniques, such as agglutination and immunodiffusion were the only ones applied, but in recent years new methods like fluorescent immunoassay, FIA, and enzyme-linked immunosorbent assay, ELISA, have been developed for use in the diagnosis and study of many bacterial diseases. Fluorescent immuno assay (FIA), and enzyme-linked imrnunosorbent assay (ELISA), were evaluated for routine diagnosis and research on the etiology of potato ring rot, (Clavibacter michiganensis subsp, sepedonicus), leaf spot and blight of begonia, (Xanthomonas campestris pv. begonia), pelargonium, (X. c. pv. pelargonii), and bacterial wilt of forage grasses (Xanthomonas campestris pv. graminis).