DATA AVAILABILITY : Our raw data and SAS code are available in FigShare DOI 10.6084/m9.figshare.21534192.
SUPPLEMENTARY MATERIAL : FIGURE S1. Global (in gray) and within environment (in color) Pearson correlations between all measured phenotypical traits for gradients 1 and 2. FIGURE S2. The effects of WGD on chlorophyll b (A) and carotenoid (B) concentration per unit fresh weight and on the relative growth rate measured using fresh weight (C), dry weight (D), and frond number (E) along gradient 1. Error bars represent 95% confidence intervals, diploids in blue and tetraploids in orange. The asterisks next to the dependent variables refer to the significance of the ploidy*strain*condition effect. FIGURE S3. The effects of WGD on chlorophyll b (A) and carotenoid (B) concentration per unit fresh weight and on the relative growth rate measured using fresh weight (C), dry weight (D), and frond number (E) along gradient 2. Error bars represent 95% confidence intervals, diploids in blue and tetraploids in orange. The asterisks next to the dependent variables refer to the significance of the ploidy*strain*condition effect. FIGURE S4. Graphical representation of the methods. TABLE S1. Origin of the strains used and link to the population genetic clusters in Xu et al. (2019). TABLE S2. Differences in the AIC values between models with stress as a categorical and as a continuous factor. TABLE S3. Post-hoc analysis (t-test) of gradient 1 (CdCl2), estimated differences, and MaxT-adjusted p values. TABLE S4. Post-hoc analysis (t-test) of gradient 2 (NaCl), estimated differences, and MaxT-adjusted p values. TABLE S5. Post-hoc analysis (t-test) of gradient 3 (NaCl), estimated differences, and MaxT-adjusted p values. TABLE S6. Post-hoc analysis of traits measured uniquely in Hoagland E medium, estimated differences, and MaxT-adjusted p values (t-test except for rootnr z-test).