Efficiency of Photosystem II and Carbon Assimilation in C4 Plants

9317756 Edwards光合作用由两个一般过程组成：一是将太阳能转化为高能中间体，二是利用这些高能中间体驱动热力学上不利的反应，使无机物转化为有机物。各种过程的效率可以从三个不同的层面来考虑：太阳能的吸收，太阳能在光化学中的利用，光化学衍生的能量用于碳同化的利用。叶绿素吸收太阳能导致形成强还原剂，并在光系统II中氧化水。通过调制光对叶绿素荧光的分析，光系统II利用太阳能的效率可以从固碳和氧的光合演化方面进行评估。本项目将在整个植物和细胞水平上进行分析，以确定C4植物物种的光系统II活性汇和碳同化中还原力的利用效率，C4植物物种具有二氧化碳浓缩机制。＊＊＊

9317756 Edwards Photosynthesis is composed of two general processes: one, the conversion of solar energy into high energy intermediates, and the other, the use of those high energy intermediates to drive thermodynamically unfavorable reactions, which results in the conversion of inorganic matter to organic matter. The efficiency of the various processes can be considered at three different levels: the absorption of solar energy, the utilization of solar energy in photochemistry, and the utilization of photochemically derived energy for carbon assimilation. Absorption of solar energy by chlorophyll results in the formation of a strong reductant and the oxidation of water at photosystem II. From analyses of chlorophyll fluorescence using modulated light, the efficiency of utilization of solar energy by photosystem II can be evaluated with respect to carbon fixation and photosynthetic evolution of oxygen. In this project, analyses will be made at the whole plant and cellular level to determine sinks for photosystem II activity and the efficiency of utilization of reductive power in carbon assimilation in C4 plant species, which have a carbon dioxide concentrating mechanism. ***