Identification of Pseudomonas savastanoi pv.savastanoi isolated from myrtle plant (Myrtus communis ) in Syria

Olive trees are grown in many regions of Syria, especially in wet regions where the olive knot disease (Pseudomonas savastanoi pv.savastanoi ) prevails .Symptoms similar to those found on olive trees have been observed on myrtle shrubs (Myrtus communis) growing naturally in some olive-grown regions. This study aimed at identifying the pathogen isolated from myrtle plant, and testing the pathogenicity of these isolates on olive trees. Morphological, biochemical and serological tests of bacteria isolated from myrtle showed similarity to those from olive and other hosts. Pathogenicity tests showed that the myrtle isolates were pathogenic on both myrtle and olive trees. Myrtle could be considered as a source of inoculum for the olive knot disease.