Ferroptosis inhibitors and DPI increase the rate of thermotolerance in Arabidopsis seedlings. (a) A. thaliana seedlings were grown on agar plates at 22°C for 6 d. Plates were pretreated as indicated for 16 h, exposed to HS (43°C for 1 h), and then returned to 22°C. The survival rate was determined 5 d after HS. Bottom panels show a representative picture of each case. Bars, 50 mm. (b) A. thaliana seedlings were grown on agar plates at 22°C for 6 d. Plates were pretreated as indicated in the dark for 16 h, exposed to HS (43°C for 1 h), and then returned to 22°C, avoiding exposure to light. The survival rate was determined 7 d after HS. (a and b) Control plates were pretreated with 1:1,000 DMSO. Each value is the mean ± SEM of at least 15 independent experiments. For each experiment, 20 seedlings per plate were tested. Different letters denote statistical difference (one-way analysis of variance, P < 0.05).