Table 3.
Content of leaf hydrogen peroxide (H2O2) and thiobarbituric acid reactive substances (TBARS) and activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione reductase (GR) in Taipei-309 and Rasi cultivars of rice (Oryza sativa L.)at 30 DAS. Plants were grown with/without high-temperature (HT) stress, and the foliage was treated with 1.6 mM ethephon (ET) at 15 DAS. Data are presented as treatment means ± SE (n = 4). The values followed by the same letters did not differ significantly by the LSD test at p < 0.05. FW, fresh weight; DAS, days after sowing.
| Cultivars | Treatments | H2O2 Content | TBARS Content | SOD Activity | APX Activity | GR Activity |
|---|---|---|---|---|---|---|
| (nmol g−1 FW) | (U min−1 mg−1 Protein) | |||||
| Taipei-309 | Control | 31.8 ± 1.70 d | 12.4 ± 0.32 de | 7.89 ± 0.32 de | 1.35 ± 0.04 fg | 0.191 ± 0.005 ef |
| HT | 94.6 ± 4.30 b | 24.8 ± 1.17 b | 10.2 ± 0.49 c | 1.94 ± 0.09 e | 0.25 ± 0.005 d | |
| ET | 22.3 ± 1.32 e | 8.2 ± 0.23 f | 12.8 ± 0.52 b | 2.85 ± 0.12 c | 0.346 ± 0.011 b | |
| ET+HT | 44.7 ± 2.10 c | 14.1 ± 0.44 cd | 15.9 ± 0.56 a | 3.72 ± 0.13 a | 0.43 ± 0.01 a | |
| Rasi | Control | 35.1 ± 1.99 d | 13.1 ± 0.37 de | 6.92 ± 0.27 e | 1.18 ± 0.03 g | 0.172 ± 0.004 f |
| HT | 112.8 ± 5.02 a | 31.5 ± 1.22 a | 8.43 ± 0.34 d | 1.62 ± 0.07 f | 0.21 ± 0.005 e | |
| ET | 29.9 ± 1.59 de | 11.2 ± 0.28 e | 10.8 ± 0.41 c | 2.35 ± 0.10 d | 0.306 ± 0.009 c | |
| ET+HT | 52.4 ± 3.01 c | 15.8 ± 0.60 c | 13.7 ± 0.51 b | 3.14 ± 0.11 b | 0.368 ± 0.010 b | |