Genetic Diversity Of Xanthomonas Oryzae Pv. Oryzae

The IS-PCR(J3,IS1112,IS1113),Rep-PCR(ERIC),HXA primers(HXA-9, HXA-14,HXA-15),and RFLP were used to analyze Xanthomonas oryzae pv.oryzae strains from China,Japan and the Philippines.First,IS-PCR and Rep-PCR were used to analyze genetic diversity of Xoo strains. The strains had variance among locations,based on the PCR result.Combined the data from four primers,6 clusters were obtained by using UPGMA analysis at level of 70% similarity.Cluster 1(60.5%) were the major clusters,this result suggested there were phylogenetic relationship between the most strains.The results of 17 tested groups(56 strains and their mono-cell-clones) showed:â…°) The percentage were 52.9%(J3),23.5%(IS1112),29.4%(IS1113) and 35.3%(ERIC) which strains and their mono-cell-clones were in one patten of each primer,respectively.â…±) UPGMA results showed only 1 group were same between strains and their mono-cell-clones of 17 tested groups,while 52.9%of dissimilarity were 30%-41%;at level of 70%similarity,12 tested groups which strains and their mono-cell clones were in one cluster(70.6%of 17 tested groups),these results suggested there were phylogenetic relationship between the strains and their mono-cell-clones.Also the differentiation were exits.Such as,strains of group Pxo79 were distributed into 3 clusters;the dissimilarity were 41%between strains and their mono-cell-clones of Pxo79,Pxo86,Pxo99,and Pxo112.These results indicated the strains were combined by different cells.â…²) There was only 11.8%of tested strains which virulence of strains were equal to their mono-cell-clones in 17 tested groups;The result indicated that there were virulent difference between strains and their mono-cell-clones.Second,We designed three PCR primers(HXA-9,HXA-14,HXA-15) based on the sequences of avr genes,in order to try to analyze the virulent of Xanthomonas oryzae pv. oryzae from China,Japan and the Philippines at molecular level.The results indicated that the genomes of tested strains contains the homologs of avr genes.Also the results indicated that the primers which designed by large fragments of avr genes were better than the primers which designed by conserve region of avr genes.3 endonucleases(EcoRI,XhoI,and Hindâ…¢) were used to digest the genomes of Xanthomonas oryzae pv.oryzae from China,Japan and the Philippines.The probes were avrXa10,central region of avrXa10,and 4 fragments HXA-14-3,HXA-15-3,HXA-15-2, HXA-15-0.7.The RFLP fingerprintings and UPGMA results showed that combines EcoRI and HXA14-3 were better than other combines in this study.Pathotypes had no relationship with PCR results,RFLP results,and UPGMA groups in this study.