Figure 1.

A, Φ_PSII of 12 Arabidopsis accessions. Error bars indicate se; n = 3. Φ_PSII was measured on plants that were grown in 100 µmol m⁻² s⁻¹ for 24 d after reaching steady-state photosynthesis in five different actinic irradiances: 100, 225, 450, 700, and 1,150 µmol m⁻² s⁻¹. B, rETR in the presence of different actinic irradiances of 12 accessions of Arabidopsis, calculated from PSII operating light use efficiencies. The inset shows the average heritabilities over three independent experiments for the individual measurement points and for the response of these values to actinic irradiance level. C, F_v′/F_m′ of 12 accessions of Arabidopsis. D, q_p in the presence of different actinic irradiances of 12 accessions of Arabidopsis. E, Correlation of Φ_PSII and NPQ of 12 accessions each with three replicates grown in 100 µmol m⁻² s⁻¹ and measured at light saturation (700 µmol m⁻² s⁻¹). F, Correlation of Φ_PSII and q_p of 12 accessions each with three replicates grown in 100 µmol m⁻² s⁻¹ and measured at light saturation (700 µmol m⁻² s⁻¹). G, Correlation of Φ_PSII and F_v′/F_m′ of 12 accessions, each with three replicates grown in 100 µmol m⁻² s^{-1 1} and measured at light saturation (700 µmol m⁻² s⁻¹). H, Correlation of NPQ and F_v′/F_m′ of 12 accessions, each with three replicates grown in 100 µmol m⁻² s^{-1 1} and measured at light saturation (700 µmol m⁻² s⁻¹).