Detection and identification of the crucifer pathogen, Xanthomonas campestris pv. campestris, by PCR amplification of the conserved Hrp/type III secretion system gene hrcC

Abstract

The development of a rapid detection method for Xanthomonas campestris pv. campestris (Xcc) in crucifer seeds and plants is essential for high-throughput certification purposes. Here we describe a diagnostic protocol for the identification/ detection of Xcc by PCR amplification of fragments from the pathogenicity-associated gene hrcC. Under stringent conditions of amplification, a PCR product of 519 bp from hrcC was obtained from a collection of 46 isolates of Xcc, with the exception of two isolates from radish. No amplicons were obtained from 39 pure cultures of the phytopathogenic bacteria Xanthomonas campestris pv. cerealicola, X. campestris pv. juglandis, X. campestris pv. pelargonii, X. campestris pv. vitians, X. arboricola pv. pruni, X. axonopodis pv. phaseoli, X. axonopodis pv. vesicatoria, X. vesicatoria, Pseudomonas syringae pv. phaseolicola, P. syringae pv. syringae, P. syringae pv. tomato, P. fluorescens, P. marginalis, Pectobacterium atrosepticum, P. carotovorum subsp. carotovorum. In addition, PCR reactions were negative for fifty unidentified environmental isolates M. Zaccardelli (&) Á F. Campanile Á A. Spasiano C.R.A-Istituto Sperimentale per le Colture Industriali, SS 18 n8 204,

Multilocus sequence typing analysis of Italian Xanthomonas campestris pv. campestris strains suggests the evolution of local endemic populations of the pathogen and does not correlate with race distribution

“…Overall, strains were collected from six regions representing more than 80% of the Italian production of brassicas and from eight different brassicas (broccoli, cabbage, cauliflower, seakale, kale, kohlrabi, Savoy cabbage and rutabaga) over a period of approximately 15 years (data not shown). The identification of these strains was confirmed by PCR with Xcc‐specific primers based on the hrcC gene (Zaccardelli et al ., ; data not shown). Representative isolates of Xcc races 1, 4 and 6 obtained from the LMG and WHRI culture collections were included for comparative purposes (Table ).…”

Plant Dynamic Metabolic Response to Bacteriophage Treatment After Xanthomonas campestris pv. campestris Infection

“…Molecular diagnosis of Xcc was carried out using the primers HrcCF2 (5 -CGTGTGGATGT GCAGACC-3 ) and HrcCR2 (5 -CAGATCTGTCT GATCGGTGTCG-3 ), which amplify an internal fragment of 519 bp of hrcC (Zaccardelli et al, 2007).…”

A Polymerase Chain Reaction Assay for the Detection ofXanthomonas campestrispv.musacearumin Banana

“…(21), variability in the rDNA sequences is limited and alternative targets are needed. Primers targeting functional genes, such as gyrB (44), endogluconase (40), the coronatine (COR) biosynthetic gene cluster, the phaseolotoxin (tox) gene cluster (5,10,11,41), fliC (47), and the hrp gene cluster (6,22,24,25,35,38,61,62), have a higher resolution than rDNA-based genes and are good candidates for speciesspecific primer development.…”