Characterizing the CO 2 -response curve in photosynthesis and photorespiration: an innovative model for C 3 plant species.

Abstract

We introduce a novel model for characterizing the CO₂-response curve in photosynthesis, addressing the limitations of the Farquhar-von Caemmerer-Berry (FvCB) model by providing a more comprehensive framework for understanding photosynthetic responses to varying CO 2 concentrations in C 3 plants. The FvCB model, while instrumental in interpreting the photosynthetic response to CO 2 , does not directly estimate critical parameters such as maximum net photosynthetic rate, transit point from RuBP- to TPU-limited photosynthesis, and the CO 2 compensation point in the presence of day respiration ( R day ). Our new model, referred to as Model I, incorporates these parameters and accounts for the R day , offering a nuanced understanding of plant physiological responses to CO₂ concentrations. The research also developed Model II, which does not require an explicit R day , addressing the challenges in measuring R day and providing an alternative for analyzing the CO₂-response curve. Both models were validated against empirical data, demonstrating their effectiveness in studying plant photosynthesis and photorespiration. The study concludes that the new models advance the FvCB model by predicting photosynthetic and photorespiratory responses under varying conditions, which is crucial for agricultural practices and ecosystem management in the context of climate change.

Plant phenotyping relevance

C3植物の光合成・光呼吸応答曲線から生理形質を推定する新規モデルを開発し、実測データで検証しており、表現型取得・推定法が研究の中心である。

Code and data availability

The paper reports gas-exchange CO2-response measurements on four C3 species analyzed with new models via the PMSS software (http://www.zipiao.tech), but provides no public phenotype dataset, raw data deposit, or author code/model deposit. The zipiao.tech URL is a commercial software product, not a paper-specific data/с

No evidence-backed public reproduction asset is currently recorded.