Photosynthetica - Ahead of Print
Characterizing the CO2-response curve in photosynthesis and photorespiration: an innovative model for C3 plant species
H.-J. KANG, T. AN, X.-L. YANG, Z.-P. YE, F.-B. WANG
Photosynthetica X:X | DOI: 10.32615/ps.2025.030 
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 CO2 concentrations in C3 plants. The FvCB model, while instrumental in interpreting the photosynthetic response to CO2, does not directly estimate critical parameters such as maximum net photosynthetic rate, transit point from RuBP- to TPU-limited photosynthesis, and the CO2 compensation point in the presence of day respiration (Rday)....
A reexamination of the Kitajima and Butler (1975) model for relating chlorophyll a fluorescence to photochemistry
I.V. KONYUKHOV, A. STIRBET, A.B. RUBIN, G. GOVINDJEE
Photosynthetica X:X | DOI: 10.32615/ps.2025.038
The main assumptions of the well-known Kitajima and Butler (1975) model, describing the relationship between the ratio of the maximum variable chlorophyll a fluorescence to the maximum fluorescence (FV/FM) and the photochemical quantum yield of PSII (ΦPo), have been analyzed. Using the experimental data from the literature, potential "weak points" of this model are discussed, as well as the reasons for the differences between the FV/FM values and the actual ΦPo values. Special attention is focused on the fluorescence measurement procedures using the saturating single...