Figure 1.

Setup for sequential stress treatments.

Arabidopsis plants were cultivated under 12 h/12 h day–night cycles (22°C at 120 μmol m⁻² s⁻¹ and 18°C in the dark) (green arrows) and treated with moderate abiotic stress conditions consisting of high light (HL), humidity, drought, heat, cold, or their combinations (orange arrows) as described in the section “Methods” before Pseudomonas syringae (Psto) or Botrytis cinerea (Bot) challenge (yellow arrows). For the recovery design, 12-day-old Arabidopsis seedlings exposed to abiotic stressors for 3 days were returned to standard conditions for three additional days before pathogen challenge. For the endpoint design, the abiotic stressors were applied to 15-day-old Arabidopsis plantlets for 3 days immediately before pathogen challenge. Plants not exposed to abiotic stressors were used to evaluate the innate immune response (control). Harvest time points for molecular analysis are indicated.