GENETIC FINGERPRINTING OF ERWINIA AMYLOVORA BY REPETITIVE SEQUENCE-PCR AND PCR-RIBOTYPING

Genomic fingerprints of Erwinia amylovora isolated from fruit trees and Rubus spp. from different geographic locations in North America and New Zealand were obtained by repetitive element-PCR (rep-PCR) and PCR-ribotyping.
For rep-PCR, outwardly-directed primers corresponding to conserved repetitive (REP, ERIC, and BOX) elements in bacteria were used to amplify sequences located between the elements.
Electrophoresis of rep-PCR products revealed identical REP-, ERIC-, and BOX-PCR fingerprints for 87% of 140 tree-fruit isolates.
Among 14 Rubus isolates, no single REP-, ERIC-, or BOX-PCR fingerprint was predominant.
Rep-PCR fingerprints were unaffected by the presence of the self-transmissible plasmid pEA34 and streptomycin-resistance determinants, whether chromosomally- or plasmid-borne.
For PCR-ribotyping, DNA primers were used to amplify sequences in the spacer region between 16S and 23S ribosomal RNA genes.
PCR-ribotype fingerprints distinguished tree-fruit isolates from Rubus isolates, but were similar among isolates within the tree-fruit group or within the Rubus group.
PCR-ribotype fingerprints were not strictly correlated with geographic origin or streptomycin-resistance phenotype.
We conclude that tree-fruit isolates of E. amylovora from widely separated geographic regions are genetically homogeneous.

VII International Workshop on Fire Blight

P.S. McManus, A.L. Jones

https://doi.org/10.17660/ActaHortic.1996.411.55