Shallow bark canker of Persian walnut (Juglans regia L.) incited by Brenneria nigrifluens is considered one of the most dangerous disease for walnut timber production. Since a number of bacterial species are frequently isolated from cankers, we developed a PCR-based method for the specific detection of B. nigrifluens. Rep-PCR performed with REP primers on B. nigrifluens, on bacteria we found associated with bark cankers (Moretti et al., J. Plant Pathol. 89: 211-218, 2007) and on Agrobacterium tumefaciens, Brenneria rubrifaciens, Erwinia amylovora, Pectobacterium carotovorum subsp. carotovorum, Pectobacterium crysanthemi, Pseudomonas syringae pv. syringae and Xanthomonas arboricola pv. juglandis, permitted us to individuate a specific fragment for B. nigrifluens which was cloned and, on the basis of its sequence, a pair of primers designed. The deduced aminoacidic sequence of the fragment has an high identity with those of an exo-poly-α-D-galacturonosidase of Yersinia enterocolitica subsp. enterocolitica and Pectobacterium chrysanthemi. The primers specifically permitted the amplification of a 310 bp amplicon when the genomic DNA of 11 B. nigrifluens strains, type strain included, was used as template. No PCR products were detected for bacteria associated with bark cankers and for the above-mentioned phytopathogenic bacteria. At the present, we are validating this PCR assay to detect B. nigrifluens in infected Persian walnut plants.
Development of a PCR-based method for detection of Brenneria nigrifluens in Persian walnut plants.
MORETTI, Chiaraluce;BUONAURIO, Roberto
2007
Abstract
Shallow bark canker of Persian walnut (Juglans regia L.) incited by Brenneria nigrifluens is considered one of the most dangerous disease for walnut timber production. Since a number of bacterial species are frequently isolated from cankers, we developed a PCR-based method for the specific detection of B. nigrifluens. Rep-PCR performed with REP primers on B. nigrifluens, on bacteria we found associated with bark cankers (Moretti et al., J. Plant Pathol. 89: 211-218, 2007) and on Agrobacterium tumefaciens, Brenneria rubrifaciens, Erwinia amylovora, Pectobacterium carotovorum subsp. carotovorum, Pectobacterium crysanthemi, Pseudomonas syringae pv. syringae and Xanthomonas arboricola pv. juglandis, permitted us to individuate a specific fragment for B. nigrifluens which was cloned and, on the basis of its sequence, a pair of primers designed. The deduced aminoacidic sequence of the fragment has an high identity with those of an exo-poly-α-D-galacturonosidase of Yersinia enterocolitica subsp. enterocolitica and Pectobacterium chrysanthemi. The primers specifically permitted the amplification of a 310 bp amplicon when the genomic DNA of 11 B. nigrifluens strains, type strain included, was used as template. No PCR products were detected for bacteria associated with bark cankers and for the above-mentioned phytopathogenic bacteria. At the present, we are validating this PCR assay to detect B. nigrifluens in infected Persian walnut plants.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
