In the recent years, LEDs have been increasingly used in interior lighting systems because of their low energy consumption, high light-flux efficiency and their ability to maintain the light-flux value at a constant level for a long period of time.
For young exponentially growing plants this is light dependent, with a low value at high light – decreasing light flux density increases this ratio [eqns (34 ], until, at zero exponential growth rate, the ratio is 0·4 [eqn (35)].
In the case of high light experiments photosynthetic flux of 900 µmol photons m−2 s−1 has been used.
At low and high values of light flux density I0, eqn (4) approximates to (7) For low values of leaf area index, LAI [or structural mass, MCX, eqn (3)], we write [from eqn (4)] (8) Parameter β has units of per day.
In general, organic light-emitting devices (OLEDs) need to operate at higher current density levels to ensure an ample light flux.
PTOX has also been implicated in increasing the flux through the linear ETC. and subsequent increased tolerance of photosystems to high light in cold-hardened Arabidopsis thaliana[ 49].
This allows a far higher signal/noise ratio under much better reproducible geometrical conditions and at the same time a much smaller necessary light flux.
In Ranunculus glacialis, an alpine plant growing in high altitudes at high light and low temperatures, PTOX protein levels correlated with the use of alternative ETC. and enabled high fluxes through photosynthetic ETC.
