Chloroplastic NADPH-dependent alkenal/one oxidoreductase contributes to the detoxification of reactive carbonyls produced under oxidative stress

► Chloroplastic alkenal/one oxidoreductase (AOR) catalyzes the reduction of α,β-unsaturated bond in reactive carbonyls (RCs). ► AOR-knock out Arabidopsis line (aor) was used to examine endogenous effect of RCs. ► aor mutants were susceptible to methyl viologen treatment accelerating reactive oxygen species production from photosystem. ► RCs produced under oxidative stress inhibited photosystem. ► AOR contributes to the detoxification of stromal RCs produced under oxidative stress in vivo.