Figure 1.

In planta bacterial multiplication in individual and combined stressed plants. Different concentrations of Pseudomonas syringae pv. tomato DC3000 were syringe inoculated on to A. thaliana maintained under well-watered (A) and at different drought stress levels (B). The in planta bacterial number was recorded at 0, 24, 48, and 72 hpt. 0 hpt values indicate initial pathogen inoculum infiltrated at the start of the combined stress experiment (A,B). Phenotypic symptoms (for example, chlorosis) in leaves from these plants were recorded at 72 hpt (C). Water only infiltrated plants (mock treatment) were maintained for comparison with combined drought and pathogen stressed plants. Data represents the mean of three biological replicates (n = 3) and error bars show ± standard error of mean (SEM). Statistical significance using Student's t test was calculated over different time periods against bacterial multiplication at 24 hpt. Symbol * in (A) denotes significance at p < 0.05. Symbols *, †, and ‡ in (B) denotes significance for 24, 48, and 72 hpt, respectively over respective pathogen concentration (FC100%) at each time point at p < 0.05. X-axis in (B) represents bacterial concentration as CFU/mL and field capacity (%) together as combined stress. The experiment was repeated thrice and consistent results were observed. FC, field capacity (%); hpt, hours post combined stress treatment.