Study of phenotypic characteristics and genetic diversity of Pseudomonas syringae pv. Syringae, the causal agent of almond bacterial canker in Khorasan Razavi province using BOX-PCR

Bacterial canker caused by pathovars of Pseudomonas syringae Van Hall is one of the serious problems in stone fruit productions. In this research samples with canker symptoms were collected from Khorasane Razavi province during 2011–2012 and bacterial isolation was performed. The bacterial strains were identified as Pseudomonas syringae pv. syringae (Pss) on basis of LOPAT and GATTa tests and were confirmed as the causal agent of the almond bacterial canker based on the pathogenicity tests. A total of 16 isolates were characterized based on physiological and biochemical tests. The isolates showed a few differences in phenotypic characteristics. Genomic DNA from strains was used in PCR with D21 and D22 primers. To assess genetic diversity among the strains، rep-PCR analysis was performed using BOXA1R primer. Similarity matrix of the strains was calculated using the Jaccard''s coefficient and cluster analysis was performed by UPGMA method using NTSYS-pc. The strains were divided into 3 clusters with BOXA1R at 68% similarity level. The results demonstrated considerable genetic diversity among strains causing canker in almond trees.