Table I.
Photosynthetic characteristics including transpiration (Tr; as determined at 1,200 μmol m−2 s−1, approximately 25°C, and 370 μmol mol−1 CO2) and root hydraulic characteristics of TOM-NtAQP1 and control plants treated with normal irrigation and 100 mm NaCl in a controlled greenhouse
Data are given as means ± se (n, number of replicates, as indicated). Different letters in a row indicate significant differences (t test, P < 0.05). * For the root hydraulic measurements (Lp and Na discharge), plants were treated with 50 mm NaCl.
| Variable | Normal Irrigation |
Salt Irrigation |
||
|---|---|---|---|---|
| Tom-NtAQP1 (n) | Control Plants (n) | Tom-NtAQP1 (n) | Control Plants(n) | |
| AN (μmol CO2 m−2 s−1) | 24 ± 1.3 (20) a | 17 ± 1.5 (10) b,c | 17 ± 0.8 (13) b | 15 ± 0.8 (9) c |
| gs (mol water m−2 s−1) | 0.43 ± 0.04 (20) a | 0.31 ± 0.03 (10) b | 0.16 ± 0.02 (13) c | 0.16 ± 0.01 (9) c |
| Ci (μmol CO2 mol−1) | 260 ± 8 (20) a | 248 ± 6 (10) a | 151 ± 15 (13) b | 158 ± 10 (9) b |
| Tr (mmol water m−2 s−1) | 5 ± 0.4 (20) a | 4 ± 0.3 (10) b | 2.4 ± 0.3 (13) c | 2.5 ± 0.3 (9) c |
| Stomatal density (0.01 mm2) | 22 ± 1 (18) a | 24 ± 3 (12) a | 19 ± 1 (18) a | 21 ± 2 (12) a |
| Stomatal pore area (μm2) | 52.9 ± 1.1 (445) a | 29.2 ± 2.0 (110) b | 25 ± 1.1 (200) b | 16.1 ± 1.5 (74) c |
| IWUE (μmol CO2 mmol−1 water) | 4.9 ± 0.3 (20) a | 4.3 ± 0.2 (10) b | 8.2 ± 1 (13) c | 6.3 ± 0.4 (9) d |
| Lp (mm s−1 MPa−1 )* | 229 ± 68 (6) a | 225± 65 (6) a | 141 ± 53 (6) b | 66 ± 15 (6) c |
| Na discharge (pmol s−1)* |
6 ± 2 (4) a |
5 ± 2 (4) a |
38 ± 2 (4) b |
35 ± 2 (4) b |