Figure 1.
Fresh weight of leaves
Nitrate Level A: 20 mM, Nitrate Level B: 40 mM; Salt Level A: 100 mM, Salt Level B: 200 mM;
Interaction 1 Level A – Salt 100 mM + Nitrate 20 mM, Interaction 1 Level B – Salt 100 mM + Nitrate 40 mM;
Interaction 2 Level A – Salt 200 mM + Nitrate 20 mM, Interaction 2 Level B – Salt 200 mM + Nitrate 40 mM
ANOVA: Treatment:Concentration – p < 0.001. Values are expressed as means ± standard error (n = 5). The control mean is shown by the blue line, and the standard error by the blue dotted lines.
Table 1.
Electrical conductivity (EC) of soil (mean ± se, n = 5)
| Treatment | Concentration | EC soil mean ± se, μS/cm | |
|---|---|---|---|
| 1 | Interaction 2 | Level B | 1331 ± 18.6a |
| 2 | Interaction 2 | Level A | 1167 ± 27.2b |
| 3 | Interaction 1 | Level B | 1002 ± 14.9c |
| 4 | Salt | Level B | 959 ± 4.17c |
| 5 | Interaction 1 | Level A | 855 ± 7.40d |
| 6 | Salt | Level A | 603 ± 13.3e |
| 7 | Nitrate | Level B | 316 ± 7.02f |
| 8 | Nitrate | Level A | 166 ± 5.22g |
| 9 | Control | Water | 27.2 ± 1.39 |
Figure 2.
Electrical conductivity of leaves
Nitrate Level A – 20 mM, Nitrate Level B – 40 mM; Salt Level A – 100 mM, Salt Level B – 200 mM;
Interaction 1 Level A – Salt 100 mM + Nitrate 20 mM, Interaction 1 Level B – Salt 100 mM + Nitrate 40 mM;
Interaction 2 Level A – Salt 200 mM + Nitrate 20 mM, Interaction 2 Level B – Salt 200 mM + Nitrate 40 mM
ANOVA: Treatment:Concentration – p < 0.05. Values are expressed as means ± standard error (n = 5). The control mean is shown by the blue line, the standard error by the blue dotted lines.
Figure 3.
MDA content (nmol/g FW) in lettuce leaves depending on treatment and concentration
Nitrate Level A – 20 mM, Nitrate Level B – 40 mM, Salt Level A – 100 mM, Salt Level B – 200 mM;
Interaction 1 Level A – Salt 100 mM + Nitrate 20 mM, Interaction 1 Level B – Salt 100 mM + Nitrate 40 mM;
Interaction 2 Level A – Salt 200 mM + Nitrate 20 mM, Interaction 2 Level B – Salt 200 mM + Nitrate 40 mM
ANOVA: Treatment:Concentration – p < 0.001. Values are expressed as means ± standard error (n = 5). The control mean is shown by the blue line, the standard error by the blue dotted lines.
Figure 4.
Proline content (μg/g FW) in lettuce leaves depending on treatment and concentration
Nitrate Level A – 20 mM, Nitrate Level B – 40 mM, Salt Level A – 100 mM, Salt Level B – 200 mM;
Interaction 1 Level A – Salt 100 mM + Nitrate 20 mM, Interaction 1 Level B – Salt 100 mM + Nitrate 40 mM;
Interaction 2 Level A – Salt 200 mM + Nitrate 20 mM, Interaction 2 Level B – Salt 200 mM + Nitrate 40 mM
ANOVA: Treatment:Concentration – p < 0.001. Values are expressed as means ± standard error (n = 5). The control mean is shown by the blue line, the standard error by the blue dotted lines.
Figure 5.
Chlorophyll a content in lettuce leaves depending on treatment and concentration
ANOVA: Treatment:Concentration – p < 0.001. Values are expressed as means ± standard error (n=5). The control mean is shown by the blue line, the standard error by the blue dotted lines.
Figure 6.
Chlorophyll b content in lettuce leaves depending on treatment and concentration
ANOVA: Treatment: Concentration – p < 0.001. Values are expressed as means ± standard error (n=5). The control mean is shown by the blue line, the standard error by the blue dotted lines.
Table 2.
Chl a / Chl b ratio depending on two factors: treatment and concentration
| Treatment | Concentration | Ratio of Chl a / Chl b mean ± se | |
|---|---|---|---|
| 1 | Salt | Level A | 5.21 ± 0.350a |
| 2 | Salt | Level B | 5.03 ± 0.361ab |
| 3 | Nitrate | Level B | 4.38 ± 0.139abc |
| 4 | Nitrate | Level A | 4.18 ± 0.278abc |
| 5 | Interaction 1 | Level A | 4.11 ± 0.224abc |
| 6 | Interaction 2 | Level B | 4.08 ± 0.196abc |
| 7 | Interaction 2 | Level A | 3.96 ± 0.331bc |
| 8 | Interaction 1 | Level B | 3.16 ± 0.185c |
Figure 7.
Carotenoid content in lettuce leaves depending on treatment and concentration
ANOVA: Treatment:Concentration; p < 0.001. Values are expressed as means ± standard error (n = 5). The control mean is shown by the blue line, the standard error by the blue dotted lines.
Figure 8.
The ratio of total chlorophyll to carotenoids depending on treatment and concentration
ANOVA: Treatment: Concentration – p < 0.001. Values are expressed as means ± standard error (n=5). The control mean is shown with the blue line, and the standard error with blue dotted lines.
Figure 9.
Pearson's correlation matrix with p-values for MDA, proline, photosynthetic pigments, EC and FW