FIG 7.

Δefp suppressor mutants have increased virulence in apple tree shoots compared with that of the Δefp parent strain. Apple trees were inoculated through shoot tip wounds with the indicated E. amylovora strains, and the extent of resulting necrosis in the inoculated shoots was measured at 1-week intervals. Bars represent the extent of necrosis in 25 shoots per strain; error bars indicate SE. Within a given time point, bars sharing a letter have no statistically significant difference according to a Tukey test. This experiment was performed twice with similar results each time; results of one representative experiment are shown.