Figure 2.

Diurnal metabolite levels under low temperature conditions. Fumarate (A and B), Suc (C and D), malate (E and F), and starch (G and H) levels were determined throughout a 24-h period in plants exposed to low temperature using enzyme-linked assays. Plants of Col-0 (A, C, E, and G) and fum2.2 (B, D, F, and H) were grown under 100 µmol m² s⁻¹ light, 8 h light/16 h dark, 500 µL L⁻¹ CO₂, and 20°C light/18°C dark conditions for 8 weeks, then transferred to low temperature (4°C) for a 24-h period. Fully expanded leaves were excised and flash frozen from individual plants at 2-h intervals in the light and 4-h intervals in the dark.