Dataset Information

Activation of CO₂ assimilation during photosynthetic induction is slower in C₄ than in C₃ photosynthesis in three phylogenetically controlled experiments.

ABSTRACT:

Introduction

Despite their importance for the global carbon cycle and crop production, species with C₄ photosynthesis are still somewhat understudied relative to C₃ species. Although the benefits of the C₄ carbon concentrating mechanism are readily observable under optimal steady state conditions, it is less clear how the presence of C₄ affects activation of CO₂ assimilation during photosynthetic induction.

Methods

In this study we aimed to characterise differences between C₄ and C₃ photosynthetic induction responses by analysing steady state photosynthesis and photosynthetic induction in three phylogenetically linked pairs of C₃ and C₄ species from Alloteropsis, Flaveria, and Cleome genera. Experiments were conducted both at 21% and 2% O₂ to evaluate the role of photorespiration during photosynthetic induction.

Results

Our results confirm C₄ species have slower activation of CO₂ assimilation during photosynthetic induction than C₃ species, but the apparent mechanism behind these differences varied between genera. Incomplete suppression of photorespiration was found to impact photosynthetic induction significantly in C₄ Flaveria bidentis, whereas in the Cleome and Alloteropsis C₄ species, delayed activation of the C₃ cycle appeared to limit induction and a potentially supporting role for photorespiration was also identified.

Discussion

The sheer variation in photosynthetic induction responses observed in our limited sample of species highlights the importance of controlling for evolutionary distance when comparing C₃ and C₄ photosynthetic pathways.

SUBMITTER: Arce Cubas L

PROVIDER: S-EPMC9848656 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Activation of CO<sub>2</sub> assimilation during photosynthetic induction is slower in C<sub>4</sub> than in C<sub>3</sub> photosynthesis in three phylogenetically controlled experiments.

Arce Cubas Lucía L Vath Richard L RL Bernardo Emmanuel L EL Sales Cristina Rodrigues Gabriel CRG Burnett Angela C AC Kromdijk Johannes J

Frontiers in plant science 20230104

<h4>Introduction</h4>Despite their importance for the global carbon cycle and crop production, species with C<sub>4</sub> photosynthesis are still somewhat understudied relative to C<sub>3</sub> species. Although the benefits of the C<sub>4</sub> carbon concentrating mechanism are readily observable under optimal steady state conditions, it is less clear how the presence of C<sub>4</sub> affects activation of CO<sub>2</sub> assimilation during photosynthetic induction.<h4>Methods</h4>In this stu ...[more]

PMID: 36684779

Similar Datasets

Project description:IntroductionC4 photosynthesis is an adaptation that has independently evolved at least 66 times in angiosperms. C4 plants, unlike their C3 ancestral, have a carbon concentrating mechanism which suppresses photorespiration, often resulting in faster photosynthetic rates, higher yields, and enhanced water use efficiency. Moreover, the presence of C4 photosynthesis greatly alters the relation between CO2 assimilation and stomatal conductance. Previous papers have suggested that the adjustment involves a decrease in stomatal density. Here, we tested if C4 species also have differing stomatal responses to environmental cues, to accommodate the modified CO2 assimilation patterns compared to C3 species.MethodsTo test this hypothesis, stomatal responses to blue and red-light were analysed in three phylogenetically linked pairs of C3 and C4 species from the Cleomaceae (Gynandropsis and Tarenaya), Flaveria, and Alloteropsis, that use either C3 or C4 photosynthesis.ResultsThe results showed strongly decreased stomatal sensitivity to blue light in C4 dicots, compared to their C3 counterparts, which exhibited significant blue light responses. In contrast, in C3 and C4 subspecies of the monocot A. semialata, the blue light response was observed regardless of photosynthetic type. Further, the quantitative red-light response varied across species, but the presence or absence of a significant stomatal red-light response was not directly associated with differences in photosynthetic pathway. Interestingly, stomatal density and morphology patterns observed across the three comparisons were also not consistent with patterns commonly asserted for C3 and C4 species.DiscussionThe strongly diminished blue-light sensitivity of stomatal responses in C4 species across two of the comparisons suggests a common C4 feature that may have functional implications. Altogether, the strong prevalence of species-specific effects clearly emphasizes the importance of phylogenetic controls in comparisons between C3 and C4 photosynthetic pathways.

Project description:Photosynthesis is an important process in plants which influences their development and productivity. Many factors can control the efficiency of photosynthesis, including CO2 conductance of leaf mesophyll, which affects the CO2 availability for Rubisco. It is known that electrical stress signals can decrease this conductance, and the response is probably caused by inactivation of H+-ATPase in the plasma membrane. In the current work, we analyzed the influence of both CO2 conductance in the plasma membrane, and chloroplast envelopes and H+-ATPase activity on photosynthetic CO2 assimilation, using a two-dimensional mathematical model of photosynthesis in leaves. The model included a description of assimilation on the basis of the Farquhar-von Caemmerer-Berry model, ion transport through the plasma membrane, diffusion of CO2 in the apoplast, and transport of CO2 through the plasma membrane and chloroplast envelope. The model showed that the photosynthetic CO2 assimilation rate was mainly dependent on the plasma membrane and chloroplast envelope conductance; direct influence of the H+-ATPase activity (through changes in pH and CO2/HCO3- concentration ratio) on this rate was weak. In contrast, both changes in CO2 conductance of the plasma membrane and chloroplast envelopes and changes in the H+-ATPase activity influenced spatial heterogeneity of the CO2 assimilation on the leaf surface in the simulated two-dimensional system. These effects were also observed under simultaneous changes in the CO2 conductance of the plasma membrane and H+-ATPase activity. Qualitatively similar influence of changes in the CO2 conductance of the plasma membrane and chloroplast envelopes, and changes in the H+-ATPase activity on photosynthesis were shown for two different densities of stomata in the simulated leaf; however, lowering the density of stomata decreased the assimilation rate and increased the heterogeneity of assimilation. The results of the model analysis clarify the potential influence of H+-ATPase inactivation on photosynthesis, and can be the basis for development of new methods for remote sensing of the influence of electrical signals.

Dataset Information

Activation of CO₂ assimilation during photosynthetic induction is slower in C₄ than in C₃ photosynthesis in three phylogenetically controlled experiments.

Introduction

Methods

Results

Discussion

Publications

Activation of CO<sub>2</sub> assimilation during photosynthetic induction is slower in C<sub>4</sub> than in C<sub>3</sub> photosynthesis in three phylogenetically controlled experiments.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Activation of CO2 assimilation during photosynthetic induction is slower in C4 than in C3 photosynthesis in three phylogenetically controlled experiments.

Introduction

Methods

Results

Discussion

Publications

Activation of CO<sub>2</sub> assimilation during photosynthetic induction is slower in C<sub>4</sub> than in C<sub>3</sub> photosynthesis in three phylogenetically controlled experiments.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Activation of CO₂ assimilation during photosynthetic induction is slower in C₄ than in C₃ photosynthesis in three phylogenetically controlled experiments.