3.6 | Respiration
Dark respiration of treatment
plants increased less steeply than that of control plants (Fig. 7),
resulting in a lower Q10 (Table 4; non-overlapping 90%
credible interval). Respiration rates at a set temperature of 30°C were
not different between control and treatment plants, nor did switching
the conditions affect the plants’ R30 (Table 4). Moving
control plants to treatment conditions decreased Q10(Table 4). The acclimation metrics (Eqn. 10 and 11) indicated limited
acclimation; AcclimSetTemp was 0.86 (Table 4),
indicating that respiration at 30°C was higher in treatment plants
relative to control plants. When compared at their respective mean
nighttime temperatures (26.5 vs 29.5°C) treatment plants respired
considerably more than controls (AcclimHomeo was
0.63—or 0.66 when calculated for mean daytime temperatures). Transfer
from control to treatment caused a marginally significant decrease in
Q10 (paired two-sample t-test, t = 2.4, P =
0.08), while the transfer from treatment to control conditions did not
lead to a significant change of Q10 (Table 4).
AcclimSetTemp and AcclimHomeo were both
lower following short-term transfer than when comparing plants at their
growth conditions (Table 4). Notwithstanding the acclimation metrics,
the lower Q10 values in treatment plants resulted in
lower respiration rates at temperatures >35°C (Fig. 7).