Fig. 1

a Standard Evaluation System (SES) scores [1-9]; b Normalized chlorophyll content (as a ratio of the control); c Normalized biomass growth by SDW (as a ratio of the control) and d Shoot Na⁺/K⁺ ratio of the four wild Oryza accessions and O. sativa controls: IR29 (salt sensitive) and Pokkali (salt tolerant). Trait means (± standard errors) are shown for each genotype under 40 and 80 mM NaCl (EC = 8.7 dS m^-1) at the seedling stage. For a, b and c, asterisks indicate significant differences from the non-salinised control for the same genotype, based on Student‘s t test (*P < 0.05, **P < 0.01). For d, asterisks indicate significant differences between 40 and 80 mM based on Student‘s t test (*P < 0.05, **P < 0.01) because the ratios (as used for a to c) were so low in non-salinised controls as to be negligible, whereas the increase in ratio from 40 to 80 mM was highly relevant salt tolerance differences between genotypes