Figure 1.

Experimental design to investigate somatic stress memory in A. thaliana. Arabidopsis thaliana plants were germinated on vertical agar plates. Growth medium supplemented with NaCl (or not, control) was applied directly to the roots (priming) of 3-week-old seedlings. After 24 h seedlings were transferred to hydroponics or to soil and grown for another 10 days without salt. A second treatment was then applied either by adding NaCl to the hydroponic solution (salt stress) or by withholding water from soil-grown plants. Epigenetic, transcriptional, and physiological differences between primed and non-primed plants were analyzed at the indicated times. Size bars in the photos: 4 cm.