Song Qingfeng, Zhang Guilian, Zhu Xin-Guang
CAS Key Laboratory of Computational Biology and CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, China.
Funct Plant Biol. 2013 Mar;40(2):108-124. doi: 10.1071/FP12056.
Canopy architecture has been a major target in crop breeding for improved yields. Whether crop architectures in current elite crop cultivars can be modified for increased canopy CO2 uptake rate (Ac) under elevated atmospheric CO2 concentrations (Ca) is currently unknown. To study this question, we developed a new model of canopy photosynthesis, which includes three components: (i) a canopy architectural model; (ii) a forward ray tracing algorithm; and (iii) a steady-state biochemical model of C3 photosynthesis. With this model, we demonstrated that the Ac estimated from 'average' canopy light conditions is ~25% higher than that from light conditions at individual points in the canopy. We also evaluated theoretically the influence of canopy architectural on Ac under current and future Ca in rice. Simulation results suggest that to gain an optimal Ac for the examined rice cultivar, the stem height, leaf width and leaf angles can be manipulated to enhance canopy photosynthesis. This model provides a framework for designing ideal crop architectures to gain optimal Ac under future changing climate conditions. A close linkage between canopy photosynthesis modelling and canopy photosynthesis measurements is required to fully realise the potential of such modelling approaches in guiding crop improvements.
冠层结构一直是作物育种中提高产量的主要目标。目前尚不清楚当前优良作物品种的作物结构是否可以进行改良，以提高大气二氧化碳浓度（Ca）升高情况下的冠层二氧化碳吸收速率（Ac）。为了研究这个问题，我们开发了一种新的冠层光合作用模型，该模型包括三个部分：（i）冠层结构模型；（ii）前向光线追踪算法；（iii）C3光合作用的稳态生化模型。利用这个模型，我们证明了从“平均”冠层光照条件估算的Ac比从冠层中单个点的光照条件估算的Ac高约25%。我们还从理论上评估了当前和未来Ca条件下冠层结构对水稻Ac的影响。模拟结果表明，为了使所研究的水稻品种获得最佳的Ac，可以通过控制茎高、叶宽和叶角来增强冠层光合作用。该模型为设计理想的作物结构提供了一个框架，以便在未来气候变化条件下获得最佳的Ac。为了充分实现这种建模方法在指导作物改良方面的潜力，需要将冠层光合作用建模与冠层光合作用测量紧密联系起来。
