مقايسه برخي از ويژگي‌هاي فنوتيپي، سرولوژيكي و مولكولي جدايه هاي Pseudomonas syringae pv. syringae عامل شانكر درختان ميوه هسته‌دار و بلايت غلات

COMPARISON OF PHENOTYPIC, SEROLOGICAL AND MOLECULAR CHARACTERISTICS OF Pseudomonas syringae PV. syringae STRAINS, THE CAUSAL AGENT OF BACTERIAL CANKER OF STONE FRUITS AND BLIGHT OF CEREALS

The bacteria strains identified as Pseudomonas syringae pv. syringae are very heterogeneous and include a wide range of pathogenic bacteria on a wide range of hosts. Bacterial canker of stone fruit trees and blight of wheat and barley are the best known diseases caused by P. syringae pv. syringae (Pss). In order to identify the differentiating characteristics of Pss strains on stone fruit trees and cereals (wheat and barley), phenotypic properties of these strains were compared using 133 biochemical and nutritional tests. The result showed that the bacterial strains from both host plant groups exhibited similar reactions except for the utilization of trehalose and to some extend C£-D-melibiose. The isolates of both host plant groups showed a few differences in antibiotic sensitivity tests.Cross-inoculation tests revealed that the strains were highly specific on their main host. Two Pss strains from stone fruit trees and two strains of cereals were used to prepare polyclonal antisera. Using all antisera, the "ouchterlony double diffusion" tests revealed that the strains of both plant groups are highly distinguishable from each other. SDS-PAGE analysis of total soluble proteins showed nearly the same banding patterns between the two groups of Pss strains. But isozymic pattern of "esterase" in some extend, and "superoxide dismutase" in particular, easily differentiated the strains of these two groups from each other. The data show the heterogeneity of Pss strains and necessity of revision in their classification.