Nicotiana benthamiana growth conditions and salt treatment

Nicotiana benthamiana was grown at 21°C, 60% humidity under short day conditions (8 h : 16 h, light : dark) using the same soil mixture as described for Z. mays. Plants were singled out 1 wk after sowing. Up to 3 wk after singling out, plants were automatically watered (soaked with tap water for 30 min, twice per week). They were then removed from automatic watering and randomly split into a control and treatment group. During the first week of the treatment regime, treated plants were soaked twice with 200 mM NaCl solution in tap water for 2 h, while control plants were soaked with tap water. After a pre‐experiment showed that 200 mM treatment led to no appreciable effects on plant morphology after 10 d, treatment was switched to soaking with 400 mM NaCl solution.