Accelerated relaxation of photoprotection impairs biomass accumulation in Arabidopsis

Faster onset of photoprotection could potentially increase biomass accumulation. Indeed, this has been realized in tobacco VPZ lines by overexpression of three photoprotective proteins in parallel. To explore the range of application of this approach, we generated ArabidopsisVPZ lines. These lines triggered photoprotection more rapidly, but growth rate and biomass accumulation were impaired under fluctuating light. This implies that the strategy might interfere with other mechanisms controlling excitation energy distribution, or with source-sink relationships or plastid signalling. Faster onset of photoprotection could potentially increase biomass accumulation. However, Arabidopsis lines overexpressing three photoprotective proteins had impaired growth rate under fluctuating light, despite rapidly triggering photoprotection.