Table 2.
Effect of different thermal regimes and nutrients’ spray on superoxide dismutase (SOD), catalase (CAT), peroxidase (POX U mg−1 protein), ascorbic acid (AsA mg g−1 FW), total phenolic contents (TPC mg g−1 FW) and malondialdehyde contents (MDA nmol g−1 FW), (averaged across of squaring, flowering and boll formation stages) of cotton leaves under glass house conditions.
| Thermal regimes | Nutrients | SOD | CAT | POX | ASA | TPC | MDA |
|---|---|---|---|---|---|---|---|
| 32/20 °C | Control | 37.71 d ± 2.0 | 51.33 d ± 3.13 | 34.89 c ± 0.52 | 137.92 d ± 8.63 | 4.63 d ± 0.52 | 1.37 a ± 0.65 |
| Potassium (1.5%) | 46.31 b ± 2.5 | 91.85 b ± 5.97 | 47.96 b ± 0.74 | 195.58 b ± 10.25 | 6.06 b ± 0.30 | 0.70 c ± 0.40 | |
| Zinc (0.2%) | 56.71 a ± 3.0 | 140.39 a ± 8.82 | 50.96 a ± 0.98 | 207.39 a ± 12.35 | 7.27 a ± 0.41 | 0.60 d ± 0.35 | |
| Boron (0.1%) | 42.78 bc ± 2.3 | 68.57 c ± 4.35 | 35.23 c ± 0.56 | 177.94 c ± 8.75 | 5.18 c ± 0.25 | 0.96 b ± 0.48 | |
| 45/30 °C | Control | 55.16 d ± 2.8 | 83.10 d ± 4.54 | 50.17 d ± 0.78 | 170.12 c ± 11.20 | 8.00 c ± 0.41 | 2.04 a ± 0.14 |
| Potassium (1.5%) | 87.41 b ± 5.1 | 258.73 b ± 13.65 | 100.62 b ± 1.5 | 328.44 a ± 22.10 | 14.25 b ± 0.70 | 0.96 c ± 0.051 | |
| Zinc (0.2%) | 111.83 a ± 6.2 | 310.77 a ± 16.31 | 104.79 a ± 1.3 | 337.90 a ± 20.30 | 15.23 a ± 0.84 | 0.87 d ± 0.044 | |
| Boron (0.1%) | 70.66 c ± 3.7 | 189.87 c ± 10.19 | 77.48 c ± 0.92 | 250.51 b ± 14.50 | 10.38 d ± 0.52 | 1.26 b ± 0.065 | |
| 38/24 °C | Control | 47.23 d ± 2.4 | 66.17 d ± 3.60 | 41.70 d ± 0.58 | 156.32 c ± 8.4 | 5.24 d ± 0.32 | 1.63 a ± 0.70 |
| Potassium (1.5%) | 64.70 b ± 3.5 | 109.91 b ± 6.63 | 57.99 b ± 0.71 | 228.12 a ± 14.45 | 7.48 b ± 0.40 | 0.77 c ± 0.50 | |
| Zinc (0.2%) | 73.58 a ± 3.8 | 160.17 a ± 9.22 | 61.25 a ± 0.88 | 230.39 a ± 16.76 | 8.06 a ± 0.50 | 0.69 d ± 0.41 | |
| Boron (0.1%) | 51.29 c ± 2.8 | 85.16 c ± 4.62 | 48.71 c ± 0.64 | 205.57 b ± 11.20 | 6.21 c ± 0.35 | 1.08 b ± 0.64 | |
| LSD | 3.65 | 5.72 | 2.94 | 11.78 | 0.49 | 0.068 |
Values are the means of three replications (n = 4) ± SE and variants possessing the same letters are not statistically significant at P < 0.05. Main factors and interaction are significant at P < 0.01. Lettering is done separately for each thermal regime using the LSD of the interaction between thermal regimes and nutrients’ spray.