Figure 6

Water use efficiency (WUE) (A) of chrysanthemum plants grown under different light intensits (75, 150, 300, and 600 µmol m−2 s−1) and nitrogen (N) concentrations (5, 10, and 15 mM N) at 70 days of cultivation. The correlation between WUE with performance index per absorbed light (PIABS), total biomass, WSC, and C:N ration of plants fed by 5 mM N with under differenty light intensities (150, 300, and 600 µmol m−2 s−1) compared to that of plants under 75 µmol m−2 s−1 (B). Vertical bars are means ± SD. Within each graph, interactive effects of light intensity and nitrogen concentration are shown. Different letters (a–d) denote a significant difference between treaments (P < 0.05).