E. amylovora was inoculated into apple stems with different genes that encode to aiiA and yhjH proteins. In such cases, disease was visible three days after inoculation and was developed to similar levels gradually until it reached the 8th day and the disease considerably increased its expansion through the leaf. However, differences in disease development both the severity of disease and the time of disease onset) were seen both between the Erwinia amylovora wild ones and Erwinia amylovora aiiA. Bacterial inocula were prepared by growing an overnight culture of E.amylovora electroporated with aiiA in LB broth enriched with sucrose at 28°C in a shaking incubator.