Table II.
Effects of various growth conditions leading to different PSII excitation pressures (as indicated by V) on the maximal quantum yield of PSII photochemistry [(Fm − Fo)/Fm], the half time (t1/2) of the chlorophyll fluorescence rise in the presence of DCMU, and the E of O2 evolution in barley leaves
| Growth Condition | V | (Fm − Fo)/Fm | t1/2 | E |
|---|---|---|---|---|
| μmol photons m−2 s−1 | ms | |||
| Air | ||||
| 400 | 0.13 | 0.78 ± 0.01 | 16.2 ± 1.7 | 1.26 ± 0.02 |
| 1500 | 0.52 | 0.75 ± 0.01 | 21.1 ± 1.4 | 1.24 ± 0.03 |
| 70 ppm CO2, 10% O2 | ||||
| 750 | 0.47 | 0.75 ± 0.02 | 10.7 ± 2.1 | 1.29 ± 0.03 |
Plants were grown for 8 d under the different gas and light conditions. Data are means ± sd of three separate experiments.