Fig. 7: Phytotoxicity and plant protection by C₁₂-G⁺, C₁₈-NMe₃⁺, and C₁₈-SMe₂⁺ in wheat and rice.

a, b Phytotoxicity of C₁₂-G⁺, C₁₈-NMe₃⁺, and C₁₈-SMe₂⁺ in wheat (a) and rice (b). See also Supplementary Fig. 8a. c Septoria wheat blotch disease symptoms on wheat leaves, pre-treated with C₁₂-G⁺, C₁₈-NMe₃⁺, and C₁₈-SMe₂⁺. Dark spots represent melanised pycnidia. See also Supplementary Fig. 8b. d Rice blast disease symptoms on rice leaves. Dark areas represent necrotic lesions. See also Supplementary Fig. 8b. e Disease symptoms in wheat after treatment with various concentrations of C₁₂-G⁺, C₁₈-SMe₂⁺, and C₁₈-NMe₃⁺. Note that C₁₈-SMe₂⁺ provides greatest protection against fungal infection. f Disease symptoms in rice after treatment with various concentrations of C₁₂-G⁺, C₁₈-SMe₂⁺, and C₁₈-NMe₃⁺. Note that C₁₈-SMe₂⁺ provides greatest protection against fungal infection. g Comparison of disease symptoms in wheat, pre-treated with C₁₂-G⁺, C₁₈-NMe₃⁺, and C₁₈-SMe₂. h Comparison of disease symptoms in rice, pre-treated with C₁₂-G⁺, C₁₈-NMe₃⁺, and C₁₈-SMe₂⁺. i DAB staining of rice leaves at 6 h after treatment with C₁₂-G⁺, C₁₈-NMe₃⁺, and C₁₈-SMe₂⁺. j Quantitative comparison of DAB precipitation in rice leaves at 6 h after spraying with C₁₂-G⁺, C₁₈-NMe₃⁺, and C₁₈-SMe₂⁺. Note that no DAB reaction was seen at 2 h after treatment. k Effect of C₁₈-SMe₂⁺ on rice growth (Pre-spray: 14 days old; left pot), control and C₁₈-SMe₂⁺-treated plants: 42 days old (middle and right pot). l Fresh weight of rice plants, grown for 14 days (Pre-spray) and 42 days (Control and C₁₈-SMe₂⁺). Values (e, f) are shown as mean ± SEM; sample sizes are indicated in graphs. g, h, j, lWhiskers’ plots, with 25th/75th percentiles (blue lines), medians (red line), and minimum and maximum (whiskers ends). Sample size n is indicated in each panel. Non-parametric Mann–Whitney testing in (g, h, j, l); statistical comparisons are indicated by brackets; in absence of brackets comparison with negative control is shown; n.s. non-significant difference (P = 0.1029) (I); *P = 0.0102 (j) and P = 0.0409 (l); **P = 0.0017 (g) and P = 0.0052 (j); ***P = 0.001 (g) and P < 0.0001 (h, j). All P-values are two-tailed. See Supplementary Table 7 for experimental conditions. All source data are provided as a Source Data file.