Table 2.
Photosynthetic rate (P s), stomatal conductance (g s), intercellular CO2 (C i), transpiration rate (E), water use efficiency (WUE), F v/F m (the maximal photochemical efficiency), photosystem I activity (PS-I), photosystem II activity (PS-II), whole chain electron transport chain, ATP and NADPH contents of control, and As treated A. annua plants. Measurements were conducted when plants were 8-month old.
| Physiological parameters | Control | 100 µM | 150 µM |
|---|---|---|---|
| P s (µmol CO2 m−2 s−1) | 31.7 ± 0.43a | 30.0 ± 0.78b | 23.5 ± 0.99c |
| g s (mol H2O m−2 s−1) | 0.44 ± 0.04a | 0.36 ± 0.07a | 0.34 ± 0.08a |
| C i (ppm) | 201.0 ± 8.9a | 189.0 ± 9.7a | 212.0 ± 5.7a |
| E (mmol H2O m−2 s−1) | 6.1 ± 0.45a | 6.08 ± 0.67a | 6.02 ± 0.54a |
| WUE (µmol mol−1) | 3.2 ± 0.02b | 5.1 ± 0.82a | 4.9 ± 1.1a |
| F v/F m | 0.82 ± 0.01a | 0.79 ± 0.02a | 0.72 ± 0.04b |
| PS-I activity (µmol O2 consumed mg−1Chl h−1) | 250 ± 9.01c | 375 ± 11.0a | 279 ± 10.0b |
| PS-II activity (µmol O2 evolved mg−1Chl h−1) |
225 ± 11.0a | 199 ± 12.0b | 154 ± 12.0c |
| Whole chain (µmol O2 evolved mg−1Chl h−1) |
148 ± 12a | 149 ± 22.3a | 109 ± 11b |
| ATP (µmol g−1 FW) | 0.37 ± 0.07a | 0.40 ± 0.12a | 0.29 ± 0.07a |
| NADPH (nmol g−1 FW) | 5.17 ± 0.61b | 7.12 ± 0.82a | 3.91 ± 0.71b |
All values are mean ± SD (n = 6). Different letters show significantly different values (P < 0.05, DMRT).