All data deposited Hubbart at al .xlsx

High sunlight can raise plant growth rates but can potentially cause cellular damage. The likelihood of deleterious effects is lowered by a sophisticated set of photoprotective mechanisms, one of the most important being the controlled dissipation of energy from chlorophyll within photosystem II (PSII) measured as non-photochemical quenching (NPQ). Although ubiquitous, the role of NPQ in plant productivity remains uncertain because it momentarily reduces the quantum efficiency of photosynthesis. Here we used plants over- expressing the gene encoding a central regulator of NPQ, the protein PsbS, within a major crop species (rice) to assess the effect of photoprotection at the whole canopy scale. We accounted for canopy light interception, to our knowledge for the first time in this context. We show that in comparison to wild-type plants, psbS overexpressors increased canopy radiation use efficiency and grain yield in fluctuating light, demonstrating that photo- protective mechanisms should be altered to improve rice crop productivity.强光照可提升植物生长速率，但亦可能引发细胞损伤。一系列复杂的光保护机制可降低有害效应发生的概率，其中最为关键的机制之一是对光系统II（PSII）内叶绿素能量的受控耗散，该过程以非光化学淬灭（NPQ）为量化指标。尽管非光化学淬灭（NPQ）普遍存在，但其对植物生产力的作用仍不明确，原因在于该过程会短暂降低光合作用的量子效率。本研究以主要粮食作物水稻为对象，对编码非光化学淬灭核心调控蛋白PsbS的基因进行过表达，以此在整冠层尺度下评估光保护作用的效果。据我们所知，本研究首次在该研究框架下纳入冠层光截获量的相关分析。研究结果显示，与野生型植株相比，PsbS过表达植株在波动光照环境下提升了冠层辐射利用效率与籽粒产量，这表明可通过调控光保护机制来提升水稻的作物生产力。