Overexpression of the violaxanthin de-epoxidase confers faster NPQ and photosynthesis induction in rice

Abstract

Plants in the field experience fluctuations in light conditions. Plants with swift responses to dynamic light conditions usually gain competitive advantage in the field. The dynamic photosynthesis can be reflected in dynamic changes in almost all processes in photosynthesis, with dominant factors being dynamic changes in non-photochemical quenching, Rubisco activation and stomatal dynamics. Each of these dynamic responses is controlled by defined mechanisms. In this study, we showed that overexpression of VDE, an enzyme involved in the xanthophyll cycle and non-photochemical quenching, in rice resulted in faster NPQ induction, less photoinhibition, and faster photosynthesis induction, which together caused increased biomass production by about 11[~]16%. This study, demonstrating a previously unnoticed role of VDE in altering the dynamics of photosynthesis induction besides decreasing photoinhibition, offers a potential strategy to improve canopy photosynthesis through capitalizing the ability of plants to use dynamic light. HighlightThe overexpression of VDE in rice resulted in faster NPQ induction, less photoinhibition, and faster photosynthesis induction, which together caused increased biomass in field.