Figure 2. Effect of chain-length of RSLVs on Induction of HSFA2 expression and PSII activity.

Arabidopsis plants were exposed to (E)-2-hexenal (10 nmol cm⁻³) a series of RSLVs of aldehyde form (each 10 nmol cm⁻³) for 30 min, or a series of RSLVs of ketone form (each 10 nmol cm⁻³) for 30 min (upper panel). Expression of the HSFA2 gene was determined using qRT-PCR. Relative transcript levels were normalized to ACTIN2 mRNA. The expression level of the 0 h exposure sample was set to 1. Effect of RSLVs on PSII activity was determined by treatment of the indicated α, β-unsaturated aldehydes or ketones (each 25 nmol cm⁻³) for 90 min to Arabidopsis plants, and then PSII activity was measured (lower panel). The chemical structures of the RSLVs are shown above the graphs. Dotted and solid circles indicate the α, β-unsaturated carbonyl bond moieties and vinyl group, respectively. Data are means ± SE (n = 3 in upper panel, n = 5 in lower panel). Values followed by the same letter are not significantly different according to Tukey-Kramer (P < 0.05).