Figure 1. Glucose 6-phosphate content of amylopectin and starch content of wild type and mutants (gwd-c1, gwd-c2, sex1–8), lacking GWD activity, grown in light-dark cycles or under continuous light. (A) Glucose 6-phosphate (G6P) content of 32 d old plants. Leaf material for starch isolation and measurement of G6P were harvested at the end of the light phase for 8 h light/ 16 h dark cycle (yellow bars), 16 h light/ 8 h dark cycle (green bars). Values displayed for continuous light are mean of several time points as indicated in Figure 3A (blue bars). (B) Average leaf starch content of the 4 genotypes. Results in (A) and (B) for plants grown in a light-dark cycle are mean values ± SD of 3 independent biological replicates. Dots and letters indicate significant differences of values of the 4 lines of the respective growth condition (a – 8 h light/ 16 h dark cycle; b – 16 h light/ 8 h dark cycle; c – continuous light) as determined by the Student t test (•• – P < 0.05; ••• – P < 0.01).