AUTHOR=Ye Zi-Piao , Kang Hua-Jing , An Ting , Duan Hong-Lang , Wang Fu-Biao , Yang Xiao-Long , Zhou Shuang-Xi 

TITLE=Modeling Light Response of Electron Transport Rate and Its Allocation for Ribulose Biphosphate Carboxylation and Oxygenation

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.581851

DOI=10.3389/fpls.2020.581851

ISSN=1664-462X

ABSTRACT=<p>Accurately describing the light response curve of electron transport rate (<italic>J</italic>–<italic>I</italic> curve) and allocation of electron flow for ribulose biphosphate (RuBP) carboxylation (<italic>J</italic><sub>C</sub>–<italic>I</italic> curve) and that for oxygenation (<italic>J</italic><sub>O</sub>–<italic>I</italic> curve) is fundamental for modeling of light relations of electron flow at the whole-plant and ecosystem scales. The non-rectangular hyperbolic model (hereafter, NH model) has been widely used to characterize light response of net photosynthesis rate (<italic>A</italic><sub>n</sub>; <italic>A</italic><sub>n</sub>–<italic>I</italic> curve) and <italic>J</italic>–<italic>I</italic> curve. However, NH model has been reported to overestimate the maximum <italic>A</italic><sub>n</sub> (<italic>A</italic><sub>nmax</sub>) and the maximum <italic>J</italic> (<italic>J</italic><sub>max</sub>), largely due to its asymptotic function. Meanwhile, few efforts have been delivered for describing <italic>J</italic><sub>C</sub>–<italic>I</italic> and <italic>J</italic><sub>O</sub>–<italic>I</italic> curves. The long-standing challenge on describing <italic>A</italic><sub>n</sub>–<italic>I</italic> and <italic>J</italic>–<italic>I</italic> curves have been resolved by a recently developed <italic>A</italic><sub>n</sub>–<italic>I</italic> and <italic>J</italic>–<italic>I</italic> models (hereafter, Ye model), which adopt a nonasymptotic function. To test whether Ye model can resolve the challenge of NH model in reproducing <italic>J</italic>–<italic>I</italic>, <italic>J</italic><sub>C</sub>–<italic>I</italic> and <italic>J</italic><sub>O</sub>–<italic>I</italic> curves over light-limited, light-saturated, and photoinhibitory <italic>I</italic> levels, we compared the performances of Ye model and NH model against measurements on two C<sub>3</sub> crops (<italic>Triticum aestivum</italic> L. and <italic>Glycine max</italic> L.) grown in field. The results showed that NH model significantly overestimated the <italic>A</italic><sub>nmax</sub> and <italic>J</italic><sub>max</sub> for both species, which can be accurately obtained by Ye model. Furthermore, NH model significantly overestimated the maximum electron flow for carboxylation (<italic>J</italic><sub>C-max</sub>) but not the maximum electron flow for oxygenation (<italic>J</italic><sub>O-max</sub>) for both species, disclosing the reason underlying the long-standing problem of NH model—overestimation of <italic>J</italic><sub>max</sub> and <italic>A</italic><sub>nmax</sub>.</p>