AFLP fingerprinting: an efficient technique for detecting genetic variation of Xanthomonas axonopodis pv. manihotis.
Xanthomonas axonopodis pv. manihotis (Xam) is the causative agent of cassava bacterial blight (CBB), a worldwide disease that is particularly destructive in South America and Africa. CBB is controlled essentially through the use of resistant varieties. To develop an appropriate disease management strategy, the genetic diversity of the pathogen's populations must be assessed. Until now, the genetic diversity of Xam was characterized by RFLP analyses using ribotyping, and plasmid and genomic Xam probes. We used AFLP (amplified fragment length polymorphism), a novel PCR-based technique, to characterize the genetic diversity of Colombian Xam isolates. Six Xam strains were tested with 65 AFLP primer combinations to identify the best selective primers. Eight primer combinations were selected according to their reproducibility, number of polymorphic bands and polymorphism detected between Xam strains. Forty-seven Xam strains, originating from different Colombian ecozones, were analysed with the selected combinations. Results obtained with AFLP are consistent with those obtained with RFLP, using plasmid DNA as a probe. Some primer combinations differentiated Xam strains that were not distinguished by RFLP analyses, thus AFLP fingerprinting allowed a better definition of the genetic relationships between Xam strains.
Restrepo
Silvia
S
Biotechnology Unit, Centro Internacional de Agricultural Tropical (CIAT), AA 6713, Cali, Colombia.
Duque
Myriam
M
Biotechnology Unit, Centro Internacional de Agricultural Tropical (CIAT), AA 6713, Cali, Colombia.
Tohme
Joe
J
Biotechnology Unit, Centro Internacional de Agricultural Tropical (CIAT), AA 6713, Cali, Colombia.
Verdier
Valérie
V
Institut Français de Recherche Scientifique pour le Développement en Coopération (ORSTOM), Genetrop, Unité de Phytopathologie, BP5045, 34032 Montpellier, France.|Biotechnology Unit, Centro Internacional de Agricultural Tropical (CIAT), AA 6713, Cali, Colombia.
D015373:Bacterial Typing Techniques; D016000:Cluster Analysis; D016172:DNA Fingerprinting / Q000379:methods*; D017931:DNA Primers / Q000235:genetics; D015342:DNA Probes; D004591:Electrophoresis, Polyacrylamide Gel; D005819:Genetic Markers / Q000235:genetics; D014644:Genetic Variation; D006239:Haplotypes / Q000235:genetics; D002365:Manihot / Q000382:microbiology; D008970:Molecular Weight; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014974:Xanthomonas / Q000145:classification / Q000235:genetics*
D017931:DNA Primers; D015342:DNA Probes; D005819:Genetic Markers