Figure 3.

Effect of supplemental UV radiation on tomato resistance to Pseudomonas syringae (Pst) pv. tomato DC3000. Bacterial population was determined at (a) 1 h and (b) 5 days after inoculation in control (UV) and high UV-treated Moneymaker, Castlemart, defenceless-1 (def-1), and odorless (od-2) plants. Plants were treated with supplemental control (no UV) or high UV for 30 min d⁻¹ (0.422 kJ m⁻² d⁻¹) for 28 days, and subsequently inoculated with P. syringae. Values represent the mean of Log transformed colony forming units (cfu) (+SEM) of five biological replicates, each replicate consisting of three leaf-discs taken from the second, third and fourth youngest leaves from the apex, respectively. Data on cfu determined at 5 days were log transformed prior statistical analysis. Different letters above bars denote significant differences among groups tested by GLM followed by Fisher´s LSD test (P ≤ 0.05). The overall effects of genotype (g), UV, and their interaction tested by two-way ANOVA are indicated.