همگني جدايه هاي عامل بلايت باكتريايي گردو در استانهاي مركزي و شمالي ايران

Bacterial blight of walnut caused of Xanthomonas arboricola pv. juglandis is widespread throughout the central and northern provinces of Iran. To evaluate the heterogeneity of the strains in various regions of the country, 48 strains of the causal bacterium were isolated from diseased leaves, twigs and shells collected form Qazvin, Hamadan, Tehran, Markazi, Aradabil, Guilan, Mazandaran and Golestan provinces and were characterized. Strains appeared to be very similar in phenotypic features and in pathogenicity. They reacted differently in tests for hydrolysis of starch, gelatin and casein, tolerance to NaCl and utilization of sorbitol and L-alanine. The electrophoretic profiles of cell proteins of the strains were very similar to each other and to that of a reference strains of X. a. pv. juglandis. The results indicate that the strains causing bacterial blight of walnut in various regions of the country are fairly homogeneous and differ from each other in only a few phenotypic features.