光合电子流(J)的不同流向和分配决定了植物的光合能力，是光合作用研究的重要内容之一。Farquhar等构建的模型(简称FvCB模型)是描述C3植物光合碳同化机理的重要模型。然而，在FvCB模型涉及1,5-二磷酸核酮糖(RuBP)再生限制的子模型中，因引入非直角双曲线模型而高估植物的最大光合电子流(Jmax)，导致FvCB模型显著高估植物的光合能力。本项目在理论上拟从J流向NADP+和流向环式电子入手，综合化学计量学方法、微分方程和光合作用理论等研究RuBP再生限制时Jmax的高估问题；实验上，拟用人工电子受体甲基紫精破坏PSI以外电子传递链，研究JNADP+对I和Ci的响应关系；利用硫酸甲酯吩嗪研究Jcyc对I和Ci的响应关系。这些关系的明晰对完善FvCB模型，提高人们对植物响应环境变化的预测能力，改进与碳同化有关的冠层模型和全球碳循环模型研究等具有十分重要的理论价值和现实意义。

The different directions and allocation of photosynthetic electrons (J) determine the photosynthetic capacity of plants, which is one of the important research contents of photosynthesis. Model of Farquhar et al. (hereafter, FvCB model) is an important model to describe the mechanism of photosynthetic carbon assimilation in C3 plants. However, as it is involved in ribulose -1,5- diphosphate (RuBP) regeneration limited sub-model in the FvCB model, due to the introduction of non-rectangular hyperbolic model (hereafter, NH model) and the model significantly overestimates the maximum photosynthetic electron flow (Jmax), which leads to overestimate the photosynthetic capacity of plants for the description of plant regeneration RuBP regernation limit stage. Therefore, the FvCB can not represent the true carbon the mechanism of plant assimilation and photosynthetic physiological characteristics. In theory, this project intends to start with J-to-NADP+and flow-to-ring electrons, synthetically using photosynthesis, chemometrics and differential equations to study carbon assimilation and overestimation of Jmax in RuBP regeneration limitation; in experiment, it intends to use artificial electron acceptor methyl viologen to destroy the electron transfer chain outside PSI, to investigate the response of JNADP+to I and Ci; and to use methyl phenazine sulfate to study the response of Jcyc to I and Ci. The clarity of these relationships is of great theoretical value and practical significance for improving the FvCB model, improving people's ability to predict plant response to environmental changes, and improving the canopy model of photosynthesis and global carbon cycle model of carbon assimilation.