Figure 7.

Effects of CB on the expression of PR1 and PDF1.2 genes during E. chrysanthemi infection. A, Col-0 leaves were infiltrated with 10 mm MgSO₄ or 10⁷ colony-forming units mL⁻¹ bacterial suspension of E. chrysanthemi wild type (E.ch) or CB negative mutant (E.ch cbs). Leaves were harvested at the indicated times after treatment. Expression patterns of PR1 (SA pathway) and PDF1.2 (ET/JA pathway) were monitored by RT-PCR. The constitutive EF1α gene was used as a control. B, RT-PCR using RNAs extracted from leaves 24 h after treatment with 0.05% (w/v) methanol (cont), JA, or JA + CB. C, Plants were infiltrated with water or CB 48 h before inoculation with a bacterial suspension of wild-type E. chrysanthemi cells. Leaves were harvested at the times indicated after bacterial infiltration, and then bacterial counts were performed as indicated in “Materials and Methods.” n = 6, error bars indicate sd, and the asterisk indicates a significant difference from the control using the Mann-Whitney test (P < 0.05).