Table III.
Photosynthetic parameters of ntrc and Col-0 grown under different photoperiods
Maximal carboxylation rate of Rubisco (Vcmax), maximal electron transport rate (Jmax), and the rate of mitochondrial respiration in light (Rd) were obtained by modeling the CO2 assimilation responses presented in Supplemental Figure S2 according to Farquhar et al. (1980). Fv/Fm represents the photochemical efficiency of PSII. Activation state of MDH was calculated as a proportion of initial activity to maximal activity. LD, Long day; SD, short day. Data are means ± se; n = 3 to 4 in all experiments. *** P < 0.005, ** P < 0.05 by Student's t test.
| Sample and Conditions | Fv/Fm | Vcmax | Jmax | Rd | Activation State of MDH |
|---|---|---|---|---|---|
| μmol CO2 m−2 s−1 | μmol m−2 s−1 | μmol m−2 s−1 | % | ||
| Col-0 SD | 0.80 ± 0.004 | 21.1 ± 1.8 | 44.1 ± 4.0 | 2.0 ± 0.4 | 51 ± 4 |
| ntrc SD | 0.66 ± 0.016*** | 27.0 ± 3.2 | 44.5 ± 5.1 | 4.1 ± 0.6** | 41 ± 6 |
| Col-0 LD | 0.82 ± 0.002 | 19.6 ± 0.8 | 44.0 ± 0.4 | 0.9 ± 0.2 | 31 ± 7 |
| ntrc LD | 0.80 ± 0.008** | 22.5 ± 1.4 | 37.9 ± 1.9 | 1.8 ± 0.2** | 24 ± 7 |