Wang Guojiao, Zeng Faliang, Song Peng, Sun Bei, Wang Qi, Wang Jiayu
Rice Research Institute, Shenyang Agricultural University, Shenyang, Liaoning, 110866, China.
Rice Research Institute, Shenyang Agricultural University, Shenyang, Liaoning, 110866, China.
J Plant Physiol. 2022 May;272:153669. doi: 10.1016/j.jplph.2022.153669. Epub 2022 Mar 23.
To elucidate the photosynthetic performance of rice mutant with low chlorophyll content, we assessed light energy conversion and photosynthetic electron transport at the flowering stage in rice of yellow-green leaf mutant (ygl) and a control with normal pigment content (IR36) under field conditions. The results showed that the reduced chlorophyll content and high expression levels of chlorophyll-binding protein genes suggested that ygl has smaller light-harvesting chlorophyll antennae. The small chlorophyll antenna size reduced non-photochemical quenching (NPQ) and generation of reactive oxygen species (ROS), and increased PSII efficiency in ygl. Analysis of the chlorophyll a fluorescence transient showed that the higher ratio of reaction-center chlorophylls and the total chlorophyll of PSII (γ) improved excitation energy capture and electron transport efficiency of PSII in ygl. The IP amplitude (ΔV) and the reduction rates of the pool of end electron acceptors in ygl increased, compared with IR36. These results suggest that the light absorbed by the mutant with reduced chlorophyll content was more efficiently partitioned to photosynthesis and could be used to improve photosynthetic efficiency.
为阐明叶绿素含量低的水稻突变体的光合性能，我们在田间条件下评估了黄绿色叶片突变体（ygl）水稻和色素含量正常的对照品种（IR36）在开花期的光能转换和光合电子传递。结果表明，叶绿素含量降低以及叶绿素结合蛋白基因的高表达水平表明ygl具有较小的捕光叶绿素天线。较小的叶绿素天线尺寸降低了ygl中的非光化学猝灭（NPQ）和活性氧（ROS）的产生，并提高了PSII效率。叶绿素a荧光瞬变分析表明，PSII反应中心叶绿素与总叶绿素的较高比率（γ）提高了ygl中PSII的激发能捕获和电子传递效率。与IR36相比，ygl中的IP振幅（ΔV）和末端电子受体库的还原率增加。这些结果表明，叶绿素含量降低的突变体吸收的光更有效地分配到光合作用中，并可用于提高光合效率。
