Microscopy. Light microscopy, coupled with scanning (SEM) and transmission(TEM) electron microscopy, was used to
study bacteria-host plant tissue interactions and to confirm immunological identification.Cucumbers (cv. Discover) were
grown to the three-leaf stage in the greenhouse and stab inoculated with E. tracheiphila.Petioles of E. tracheiphila–
infected cucumbers were fixed 2 weeks after inoculation. For Nomarski interference contrast light microscopy, petioles
were fixed in 1% formaldehyde and 2% glutaraldehyde in 0.01 M phosphate buffer(pH 7), postfixed in 1% osmium tetroxide
in 0.01 M phosphate buffer (pH 7), dehydrated in an ethanol series, and then embedded in LR White resin (32).