RESUMEN
The aim of this study was to develop a method to detect a point mutation in the ribosomal S12 protein (rpsL) gene in streptomycin-resistant strains of Xanthomonas oryzae pv. oryzicola and X. oryzae pv. oryzae. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was developed to detect a point mutation in codon 43 of the rpsL gene in X. oryzae pv. oryzicola and X. oryzae pv. oryzae. The 304-bp PCR product from the rpsL gene was digested by MboII to form two fragments (201 and 103 bp) if there was a mutation at codon 43, or three fragments (146, 103, and 55 bp) if there was no mutation. Compared with the results from nucleotide sequencing, the PCR-RFLP method was accurate in detecting the point mutation at codon 43 of the rpsL gene in streptomycin-resistant strains of X. oryzae pv. oryzicola and X. oryzae pv. oryzae. These results indicate that the PCR-RFLP is a simple, rapid and reliable method for detecting the point mutation at codon 43 of the rpsL gene.
