Figure 9.

Effects on Net Photosynthetic Rates and CO₂ Compensation Points.

(A) Net photosynthetic rates of plants grown with a 10-h or a 14-h light period.

(B) CO₂ compensation points at 21% oxygen of plants grown with a 10-h or a 14-h light period.

Fully expanded rosette leaves were analyzed at developmental stage 5.1 (Boyes et al., 2001). Bars show mean values ± sd from measurements with five individual plants per line. Asterisks indicate significance levels in comparison with the wild type (* P < 0.05, ** P < 0.01). The double mutant flowers very early at the longer photoperiod, which rendered the acquisition of comparable data impossible for these conditions. Wild type, white bars; hpr2-1, light gray bars; hpr1-1, dark gray bars; hpr1-1 hpr2-1, black bars.