Rapid and efficient identification protocols for xanthomonas campestris pv. citri for quarantine investigations

Abstract

The bacterial pathogen, Xanthomonas campestris pv. citri Group A, causing Oriental canker of Citrus spp., is regarded as a serious microbial threat to New Zealand horticulture. Rapid identification following a breach of biosecurity is essential if eradication is to be achieved. Confirmation of the presence of Oriental canker pathogen can be achieved with a single primer set obtained by DNA subtraction. Primers to X campestris pv. citri Group B, a pathogen of lesser severity, causing a cankrosis B or false canker, were also developed to discriminate these two pathogens. Specificity of primers for identification of these pathogens was investigated, and the sensitivity of primers for the detection of a specific pathogen in the field was assessed using X campestris pv. pruni as a surrogate pathogen. The pathogen can be detected from plant tissue without isolating the bacterium by amplifying DNA sequences specific to the pathogen from contaminated tissue washings. © 2006 Taylor & Francis Group, LLC.