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

Accurately describing the light response curve of electron transport rate (- curve) and allocation of electron flow for ribulose biphosphate (RuBP) carboxylation ( - curve) and that for oxygenation ( - 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 ( ; - curve) and - curve. However, NH model has been reported to overestimate the maximum ( ) and the maximum ( ), largely due to its asymptotic function.

Quantifying Light Response of Leaf-Scale Water-Use Efficiency and Its Interrelationships With Photosynthesis and Stomatal Conductance in C and C Species.

Light intensity () is the most dynamic and significant environmental variable affecting photosynthesis ( ), stomatal conductance ( ), transpiration ( ), and water-use efficiency (WUE). Currently, studies characterizing leaf-scale WUE- responses are rare and key questions have not been answered. In particular, (1) What shape does the response function take? (2) Are there maximum intrinsic (WUE; WUE) and instantaneous WUE (WUE; WUE) at the corresponding saturation irradiances ( and )? This study developed WUE- and WUE- models sharing the same non-asymptotic function with previously published - and - models.

Comparing two measures of leaf photorespiration rate across a wide range of light intensities.

Suppression of photorespiration by low O concentrations (Method 1) and simultaneous measurements of gas exchange and chlorophyll fluorescence (Method 2) are often used to estimate leaf photorespiration rate (R) of C plants. However, it is largely unknown whether Method 1 and Method 2 can be used equivalently in estimating R. Using a field experiment on two wheat cultivars (T.

[Photosynthetic physio-ecological characteristics in soybean leaves at different CO concentrations].

The availability of CO, a substrate for photosynthesis, affects the photosynthesis process and photosynthate production. Using the Li-6400-40B, we measured the photosynthetic electron transport rate and the photosynthetic light-response curves of soybean (Glycine max) leaves at different CO concentrations (300, 400, 500 and 600 μmol·mol). By fitting these parameters with a mechanistic model characterizing the light response of photosynthesis, we obtained aseries of photosynthetic parameters, eco-physiological parameters, as well as the physical parameters of photosynthetic pigments.

[Light-use efficiency of tomato seedling leaves at different CO concentrations].

Light-use efficiency (LUE) is an important parameter to assess light energy absorption of leaf. Especially, it is a key factor to affect production and quality of ecosystem. A model of LUE was developed based on a mechanistic model of light-response of photosynthesis.

A mechanistic model for the photosynthesis-light response based on the photosynthetic electron transport of photosystem II in C3 and C4 species.

A new mechanistic model of the photosynthesis-light response is developed based on photosynthetic electron transport via photosystem II (PSII) to specifically describe light-harvesting characteristics and associated biophysical parameters of photosynthetic pigment molecules. This model parameterizes 'core' characteristics not only of the light response but also of difficult to measure physical parameters of photosynthetic pigment molecules in plants. Application of the model to two C3 and two C4 species grown under the same conditions demonstrated that the model reproduced extremely well (r(2) > 0.

[A study of the diversity of different geographical populations of Emmenopterys henryi using FTIR based on principal component analysis and cluster analysis].

Emmenopterys henryi, an endemic species in China, has been one of the grade II national key conservation rare and endangered plants. The spectra of stem and leaf of Emmenopterys henryi sampling from seven different geographical populations were determined by Fourier transform infrared (FTIR) spectrometry with OMNI-sampler directly, fast and accurately. A positioning technology of OMNIC E.

[FTIR spectra of endangered plants Ulmus elongata and its correlation to soil nitrogen].

Ulmus elongata, an endemic species in China, is one of the grade II national key conservation rare and endangered plants. The spectra of root, stem, skin and leaf of Ulmus elongata sampled from eight different sites were determined by Fourier transform infrared (FTIR) spectrometry with OMNI-sampler directly, fast and accurately. A positioning technology of OMNIC E.