Fig. 1: A. thaliana shows an extensive natural variation to ER stress.

a Distribution of 350 accessions based on the biomass (shoot fresh weight) ratio of TM treatment vs. untreated (DMSO) compared to the accession reference, Col-0, for which the ratio equals 1 (green and orange dots indicate Na-1 and Est-0 values, respectively). The RR for each accession is given in Supplementary Data 1. b Na-1 and Est-0 accessions selected for the QTL mapping analysis were germinated on either 25 or 50 ng mL⁻¹ TM or DMSO for 10 days. c Relative shoot weight of Col-0 (green triangles), Na-1 (blue dots), and Est-0 (purple squares) seedlings germinated on media containing the indicated concentrations of TM or DMSO grown for 10 days. Data represent means ± SEM among biological replicates (n = 21). Statistical significance was determined using a factorial linear mixed model framework followed by post-hoc testing using the two-sided Tukey’s HSD test (multiple testing-controlled threshold used was P < 0.05). d UPR gene expression analysis in Col-0 (green dots), Na-1 (blue triangles), and Est-0 (purple squares) seedlings after 3- h or 6 h pulse treatment with 0.5 μg mL⁻¹ TM or DMSO. qRT-PCR analyses were performed using specific primers for ERdj3B, spliced bZIP60 (sbZIP60) or BiP3. No differences were made to the sequence of primers used for the amplification of Est-0, Na-1, and Col-0 accessions based on the 1001 Arabidopsis genome database⁵⁶. GAPDH transcript levels were used as an internal control. Gene expression values are presented relative to DMSO control and represent the mean ratio ± SEM among biological replicates (n = 9). Statistical significance was determined by Student’s unpaired two-tailed t test (P-value is shown in the graph; ns, not significant). Source data are provided as a Source Data file.