Additional file 3: Figure S2. of Maize plants can enter a standby mode to cope with chilling stress

Effect of chilling on CO2 assimilation in two maize hybrids. The 7-day chilling treatment (10 °C day/4 °C night) was applied at about the 6-VL stage. Measurements were performed in the middle of 4th leaf blade at the end of the chilling treatment for treated plants or 1 day after the beginning of the treatment for control plants in order to compare plants at the same developmental stage. Ambient parameters were 25 °C, 380 μmol CO2 mol−1. (a) Irradiance response curves of CO2 assimilation. The irradiances used for the measurements were 2000, 1500, 1000, 800, 600, 400, 300, 150 and 0 μmol m−2 s−1 PAR. (b) Curve parameters. Initial slope was calculated between irradiance 0 and 150 μmol m−2 s−1 PAR; compensation point is the irradiance at which CO2 assimilation is 0. Data are means ± sd of 15–20 plants (5–10 individuals in 2 experiments). (PDF 349 kb)