IDENTIFICATION OF THE CAUSAL AGENT OF ANGULAR LEAF SPOT DISEASE OF CUCUMBER AND STUDING ITS PHENOTYPE CHARACTERISTICS ANDGENETIC DIVERSITY IN FARS AND KERMAN PROVINCES

During 2011-2012, 11 isolates from greenhouses of cucumber in Kerman and 14 isolates from greenhouses of cucumber in Fars provinces were isolated and identifiedas thecausal agent of angular leaf spot disease of cucumber.The isolates were investigated based on physiological, biochemical and nutritional characteristics, amplification of 560 bp with D21-D22 primers and rep-PCR with BOX and ERIC primers. On the basis of LOPAT and GATTa and other standard bacteriological tests, the isolates were identified as Pseudomonas syringae pv. Lachrymans(Psl). Numerical analysis of phenotypic characteristics of Psl isolates using Ntsys-pc software revealed that Psl isolates were homogenous. Isolates of Psl in Fars and Kerman provinces were similar inphenotypic and biochemical characteristics. They showed 83.3% similarity to Pss and 50% to P. fluorescens. Pathogenicity test oncucumber, caused angular leaf spot symptoms (water- soaked, necrotic lesions each with a large chlorotic halo)on cucumber leaves after 7 to 14 days of inoculation. The strains causedclorotic, angular leaf spot and symptoms on leavesafter inoculation on zucchini, melon, watermelon andcantaloupe too,However,the symptoms are veryclear on cucumbers other than cucurbit plantsbut did not cause symptoms on plants such as tomato, eggplant, peper. The strains were homogenesis phenotypically but on the rep-PCR with Box and Eric primers, Were divided intofour groups and there were no correlation with the geographic origin of the strains.