Acclimation of photosynthetic microorganisms to changing ambient CO2 concentration

Interactions between plants, insects and pathogens are complex and not sufficiently understood in the context of climate change. In this study, the impact of a root pathogen on a leaf-eating insect hosted by a tree species at elevated CO2 concentration is reported for the first time. The combined and isolated effects of CO2 and infection by the root pathogen Phytophthora plurivora on English oak (Quercus robur) seedlings were used to assess growth rates of plants and of gypsy moth (Lymantria dispar) larvae. For this purpose, two Q. robur provenances (Belgrade and Sombor) were used. At ambient CO2 concentration, the relative growth rates of larvae consuming leaves of plants infected by P. plurivora was higher than those consuming non-infected plants. However, at elevated CO2 concentration (1000 ppm) higher relative growth rates were detected in the larvae consuming the leaves of non-infected plants. At ambient CO2 concentration, lower growth rates were recorded in L. dispar larvae hosted in Q. robur from Belgrade in comparison to larvae hosted in Q. robur from Sombor. However, at elevated CO2 concentration, similar growth rates irrespective of the provenance were observed. Defoliation by the gypsy moth did not influence the growth of plants while P. plurivora infection significantly reduced tree height in seedlings from Belgrade. The results confirm that a rise of CO2 concentration in the atmosphere modifies the existing interactions between P. plurivora, Q. robur, and L. dispar. Moreover, the influence of the tree provenances on both herbivore and plant performance at elevated CO2 concentrations suggests a potential for increasing forest resilience through breeding.

Download Full-text

Sensitivity of wheat growth to increased air temperature for different scenarios of ambient CO2 concentration and rainfall in Victoria, Australia - a simulation study

Climate Research ◽

10.3354/cr002131 ◽

1992 ◽

Vol 2 ◽

pp. 131-149 ◽

Cited By ~ 38

Author(s):

YP Wang ◽

Jr Handoko ◽

GM Rimmington

Keyword(s):

Air Temperature ◽

Simulation Study ◽

Co2 Concentration ◽

Wheat Growth ◽

Ambient Co2

Download Full-text

Long-Term m5C Methylome Dynamics Parallel Phenotypic Adaptation in the Cyanobacterium Trichodesmium

Molecular Biology and Evolution ◽

10.1093/molbev/msaa256 ◽

2020 ◽

Author(s):

Nathan G Walworth ◽

Michael D Lee ◽

Egor Dolzhenko ◽

Fei-Xue Fu ◽

Andrew D Smith ◽

...

Keyword(s):

Global Change ◽

Co2 Concentration ◽

Adaptive Responses ◽

Short Term ◽

Modern Biology ◽

High Co2 ◽

Biological Responses ◽

Evolution Experiment ◽

Ambient Co2

Abstract A major challenge in modern biology is understanding how the effects of short-term biological responses influence long-term evolutionary adaptation, defined as a genetically determined increase in fitness to novel environments. This is particularly important in globally important microbes experiencing rapid global change, due to their influence on food webs, biogeochemical cycles, and climate. Epigenetic modifications like methylation have been demonstrated to influence short-term plastic responses, which ultimately impact long-term adaptive responses to environmental change. However, there remains a paucity of empirical research examining long-term methylation dynamics during environmental adaptation in nonmodel, ecologically important microbes. Here, we show the first empirical evidence in a marine prokaryote for long-term m5C methylome modifications correlated with phenotypic adaptation to CO2, using a 7-year evolution experiment (1,000+ generations) with the biogeochemically important marine cyanobacterium Trichodesmium. We identify m5C methylated sites that rapidly changed in response to high (750 µatm) CO2 exposure and were maintained for at least 4.5 years of CO2 selection. After 7 years of CO2 selection, however, m5C methylation levels that initially responded to high-CO2 returned to ancestral, ambient CO2 levels. Concurrently, high-CO2 adapted growth and N2 fixation rates remained significantly higher than those of ambient CO2 adapted cell lines irrespective of CO2 concentration, a trend consistent with genetic assimilation theory. These data demonstrate the maintenance of CO2-responsive m5C methylation for 4.5 years alongside phenotypic adaptation before returning to ancestral methylation levels. These observations in a globally distributed marine prokaryote provide critical evolutionary insights into biogeochemically important traits under global change.

Download Full-text

Stomatal Limitation of Photosynthesis in Abscisic Acid-Treated and in Water-Stressed Leaves Measured at Elevated CO2

Functional Plant Biology ◽

10.1071/pp9880495 ◽

1988 ◽

Vol 15 (4) ◽

pp. 495 ◽

Cited By ~ 11

Author(s):

SP Robinson ◽

WJR Grant ◽

BR Loveys

Keyword(s):

Abscisic Acid ◽

Stomatal Conductance ◽

Quantum Yield ◽

Oxygen Evolution ◽

Stomatal Closure ◽

Co2 Concentration ◽

Assimilation Rate ◽

High Co2 ◽

Co2 Concentrations ◽

Ambient Co2

Feeding 10-5M (�)-abscisic acid (ABA) via the petioles of detached leaves of apricot (Prunus armeniaca) or sunflower (Helianthus annuus) decreased stomatal conductance and assimilation rate but not the calculated intercellular CO2 concentration (Ci) suggesting non-stomatal as well as stomatal inhibition of photosynthesis. Evidence for non-stomatal inhibition was not observed in spinach (Spinacia oleracea). There was no significant decrease in rates of electron transport nor ribulosebisphosphate carboxylase (Rubisco) activity in intact chloroplasts isolated from ABA-treated sunflower leaves. Oxygen evolution by leaf discs with 3% CO2 in the gas phase was inhibited in ABA- treated sunflower and apricot leaves but not in spinach; the inhibition was only half as great as the inhibition of assimilation rate at ambient CO2. The quantum yield of oxygen evolution decreased in ABA-treated sunflower leaves in proportion to the decrease in the light-saturated rate. There was no significant difference in room temperature chlorophyll fluorescence of ABA-treated leaves compared to controls. Stomatal conductance of sunflower leaves decreased by more than 90% when the CO2 concentration was increased from 340 ppm to 1000 ppm but at much higher CO2 concentrations the stomata appeared to reopen. Stomatal conductance at 2-3% CO2 (20 000-30 000 ppm) was 50% that at ambient CO2. This reopening of stomata at high CO2 was inhibited in previously water-stressed or ABA-treated plants. In unstressed leaves, the maximum rate of oxygen evolution occurred at 0.5-2% CO2 but in ABA-treated leaves 10-15% CO2 was required for maximum rates. It is suggested that stomatal closure may limit photosynthesis in ABA-treated or previously water-stressed leaves even at the relatively high CO2 concentrations normally used in the leaf disc oxygen electrode. The inhibition of photosynthesis by ABA is largely overcome at saturating CO2. The apparent non-stomatal inhibition suggested by gas exchange measurements and the decreased quantum yield could be explained by patchy stomatal closure in response to ABA.

Download Full-text

Effect of green roof on ambient CO2 concentration

Building and Environment ◽

10.1016/j.buildenv.2010.05.025 ◽

2010 ◽

Vol 45 (12) ◽

pp. 2644-2651 ◽

Cited By ~ 97

Author(s):

Jian-feng Li ◽

Onyx W.H. Wai ◽

Y.S. Li ◽

Jie-min Zhan ◽

Y. Alexander Ho ◽

...

Keyword(s):

Green Roof ◽

Co2 Concentration ◽

Ambient Co2

Download Full-text

PHOTOSYNTHESIS OF BIRCH TAXA (Betula L.) UNDER VARIED IRRADIANCE AND CO2 CONCENTRATION

HortScience ◽

10.21273/hortsci.40.3.882e ◽

2005 ◽

Vol 40 (3) ◽

pp. 882e-883

Author(s):

Mengmeng Gu ◽

Curt R. Rom ◽

James A. Robbins ◽

Hyun-Sug Choi

Keyword(s):

Response Curve ◽

Light Response ◽

Co2 Concentration ◽

Betula Alleghaniensis ◽

Light Response Curve ◽

Deciduous Species ◽

Exchange System ◽

High Co2 ◽

Gas Exchange System ◽

Ambient Co2

The genus Betula consists of approximately 50 deciduous species throughout northern hemisphere. Net CO2 assimilation ([A]) of four birch taxa (Betula alleghaniensis Britton, B. davurica Pall., B. nigra L. `Heritage', and B. papyrifera Marsh.) was measured with a portable gas exchange system, CIRAS-I. Light was increased from 0 to 2000 μmol· m-2·s-1 at increments of 25, 50, 100, 250, 500, 750, 1000, 1250, 1500, 1750, 2000 μmol·m–2·s–1 to create an [A] light-response curve. CO2 concentration was gradually increased to 1100 ppm in increments 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100 ppm to create an [A]-Ca (ambient CO2) curve. B. davurica had significantly higher potential A capacity than the other taxa under high CO2 conditions. Betula nigra `Heritage' had the highest carboxylation efficiency among four taxa. B. davurica and B. nigra `Heritage', had higher [A] when ambient CO2 is 0ppm. Betula davurica and B. nigra `Heritage', had higher light-saturated rate of gross [A] than B. alleghaniensis and B. papyrifera.

Download Full-text

Modulations in carbon and nitrogen assimilation patterns in rice plants exposed to elevated atmospheric carbon dioxide concentrations

Journal of Environmental Biology ◽

10.22438/jeb/42/4(si)/mrn-1532a ◽

2021 ◽

Vol 42 (4(SI)) ◽

pp. 1114-1125

Author(s):

S.K. Rajkishore ◽

◽

P. Doraisamy ◽

M. Maheswari ◽

K.S. Subramanian ◽

...

Keyword(s):

Elevated Co2 ◽

Atmospheric Carbon Dioxide ◽

Nitrogen Assimilation ◽

Reductase Activity ◽

Co2 Concentration ◽

Current Recommendation ◽

Elevated Atmospheric Co2 ◽

Carbon And Nitrogen ◽

Rice Plants ◽

Ambient Co2

Aim: To study the influence of elevated atmospheric CO2 concentrations on the carbon and nitrogen assimilation patterns in rice plants. Methodology: Rice (Oryza sativa) plants were placed in Open Top Chambers (OTCs) and exposed to elevated levels of CO2. The treatments consisted of three levels of CO2 (398, 550 and 750 µmol mol-1) and three levels of nitrogen (0, 150 and 200 kg ha-1) and replicated five times in completely randomized design. Results: Leaf nitrogen was significantly reduced by 10.6 % and 6.5 % during later stages in rice plants exposed to CO2 @ 750 µmol mol-1 and 550 µmol mol-1, respectively over the ambient CO2. Rice plants under elevated CO2 did not exhibit any variations in Nitrate Reductase activity in leaves in comparison to ambient CO2 at tillering stage. Interestingly, NRase activity in leaves decreased at flowering stage whereas NRase activity in roots increased at same stage. The highest mean nitrogen values (0.58, 0.89 and 1.35 %) were observed in Camb (ambient CO2 concentration) and the lowest values (0.51, 0.80 and 1.27 %) in C750 in roots, straw and grains, respectively. Elevated CO2 @ 750 µmol mol-1 significantly increased the above ground biomass (straw and grain) by 15.6 and 40.1 %, respectively, over the ambient CO2 of 398 µmol mol-1. Interpretation: Elevated CO2 enhanced the grain productivity but affected the quality of rice grains. Thus, excessive nitrogen fertilization above the current recommendation is necessary for future high CO2 environments.

Download Full-text