Table 5.
Effects of Mg supply on photorespiration parameters of rice and cucumber.
| Species | Treatment | P n (μmol m−2 s−1) | P n2%O2 (μmol m−2 s−1) | P r (μmol m−2 s−1) | P r/P n2%O2 (%) | Γ* (μmol mol−1) |
|---|---|---|---|---|---|---|
| Rice | 0.01 mM | 14.7 ± 1.6b | 19.7 ± 1.9b | 5.0 ± 0.4a | 25.6 ± 0.6a | 37.7 ± 0.3a |
| 0.1 mM | 16.3 ± 2.3b | 20.5 ± 3.1b | 4.4 ± 1.0ab | 20.1 ± 3.2b | 33.9 ± 0.9b | |
| 1 mM | 20.2 ± 0.7a | 23.7 ± 0.7a | 3.5 ± 0.4b | 14.9 ± 1.6c | 33.7 ± 0.6b | |
| Cucumber | 0.01 mM | 9.1 ± 1.3c | 13.2 ± 1.2c | 4.1 ± 0.2b | 31.2 ± 3.4a | 40.8 ± 1.6a |
| 0.1 mM | 12.0 ± 1.0b | 16.8 ± 0.9b | 4.8 ± 0.1a | 28.6 ± 2.1a | 35.7 ± 0.6b | |
| 1 mM | 17.0 ± 0.6a | 21.3 ± 0.3a | 4.2 ± 0.3b | 19.9 ± 1.6b | 34.9 ± 2.5b |
Data represent mean ± standard deviation (SD) of three replicates for P n, P n2%O2, P r, P r/P n2%O2, and Γ*. Different letters indicate statistically significant differences (P< 0.05) between three Mg treatments.
P n, net photosynthetic rate; P n2%O2, net photosynthetic rate in 2%O2; P r, photorespiration rate; Γ*, the CO2 compensation point in the absence of mitochondrial respiration.