Acclimation to temperature and irradiance modulates PSII charge recombination

Abstract

Acclimation of wild type and the chlorina F2 mutant of barley to either high light or low temperature results in a 2‐ to 3‐fold increase in non‐photochemical quenching which occurred independently of either energy‐dependent quenching (qE), xanthophyll cycle‐mediated antenna quenching or state transitions. Results of in vivo thermoluminescence measurements used to address this conundrum indicated that excitation pressure regulates the temperature gap for and charge recombinations within photosystem II reaction centers. This is discussed in terms of photoprotection through non‐radiative charge recombination.