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

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.

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Effects of Elevated Carbon Dioxide Levels and Temperature on the Life History of the Madeira Mealybug (Hemiptera: Pseudococcidae)

Journal of Entomological Science ◽

10.18474/0749-8004-39.3.387 ◽

2004 ◽

Vol 39 (3) ◽

pp. 387-397 ◽

Cited By ~ 14

Author(s):

Juang-Horng Chong ◽

Marc W. van lersel ◽

Ronald D. Oetting

Keyword(s):

Carbon Dioxide ◽

Chemical Composition ◽

Elevated Co2 ◽

Atmospheric Carbon Dioxide ◽

Host Plants ◽

Co2 Concentration ◽

Reproductive Period ◽

Elevated Co2 Concentration ◽

Elevated Atmospheric Co2 ◽

Co2 Level

Atmospheric carbon dioxide concentrations and temperatures are increasing and, thus, the interactions between insect herbivores and their host plants in environments of elevated CO2 concentration and temperature must be examined. We investigated the combined effects of elevated atmospheric CO2 concentration (400 and 700 μmol mol−1) and temperature (20, 25 and 30°C) on the development, survival and reproduction of two generations of the Madeira mealybug, Phenacoccus madeirensis Green, and the chemical composition of chrysanthemum, Dendranthema × grandiflora Kitam., leaves. The development of the mealybugs was temperature-driven and was not influenced by the CO2 level or the number of generations. At higher temperatures, the duration to egg eclosion and the developmental time of adult females and males were significantly shortened. More eggs survived to adulthood at higher temperatures. Temperature had no influence on the egg eclosion percentage. The reproductive period of females was shortest at 30°C, while fecundity was highest at 20°C. There was a significantly higher proportion of females at the end of the experiment at lower than at higher temperatures. Elevated CO2 level and temperature did not change the chemical composition (nitrogen and carbon concentrations, and carbon-nitrogen ratio) of the host plants. Relative water content of the leaf tissues was higher at 30°C than other temperature treatments. Our results show that the effects of temperature on the biology of the Madeira mealybug were stronger than that of the elevated CO2 concentration.

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Growth Rates of Lymantria dispar Larvae and Quercus robur Seedlings at Elevated CO2 Concentration and Phytophthora plurivora Infection

Forests ◽

10.3390/f11101059 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1059

Author(s):

Slobodan Milanović ◽

Ivan Milenković ◽

Jovan Dobrosavljević ◽

Marija Popović ◽

Alejandro Solla ◽

...

Keyword(s):

Elevated Co2 ◽

Lymantria Dispar ◽

Growth Rates ◽

Quercus Robur ◽

Co2 Concentration ◽

Root Pathogen ◽

Relative Growth ◽

Elevated Co2 Concentration ◽

Relative Growth Rates ◽

Ambient Co2

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.

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Effects of Elevated Atmospheric CO2 Concentration on the Infection of Rice Blast and Sheath Blight

Phytopathology ◽

10.1094/phyto-96-0425 ◽

2006 ◽

Vol 96 (4) ◽

pp. 425-431 ◽

Cited By ~ 67

Author(s):

T. Kobayashi ◽

K. Ishiguro ◽

T. Nakajima ◽

H. Y. Kim ◽

M. Okada ◽

...

Keyword(s):

Rice Blast ◽

Soil Surface ◽

Co2 Concentration ◽

Leaf Sheath ◽

Sheath Blight ◽

Average Height ◽

Leaf Blast ◽

Elevated Atmospheric Co2 ◽

Rice Plants ◽

Sheath Blight Disease

The effect of elevated atmospheric CO2 concentration on rice blast and sheath blight disease severity was studied in the field in northern Japan for 3 years. With free-air CO2 enrichment (FACE), rice plants were grown in ambient and elevated (≈200 to 280 μmol mol-1 above ambient) CO2 concentrations, and were artificially inoculated with consist of Magnaporthe oryzae. Rice plants grown in an elevated CO2 concentration were more susceptible to leaf blast than those in ambient CO2 as indicated by the increased number of leaf blast lesions. Plants grown under elevated CO2 concentration had lower leaf silicon content, which may have contributed to the increased susceptibility to leaf blast under elevated CO2 concentrations. In contrast to leaf blast, panicle blast severity was unchanged by the CO2 enrichment under artificial inoculation, whereas it was slightly but significantly higher under elevated CO2 concentrations in a spontaneous rice blast epidemic. For naturally occurring epidemics of the sheath blight development in rice plants, the percentage of diseased plants was higher under elevated as opposed to ambient CO2 concentrations. However, the average height of lesions above the soil surface was similar between the treatments. One hypothesis is that the higher number of tillers observed under elevated CO2 concentrations may have increased the chance for fungal sclerotia to adhere to the leaf sheath at the water surface. Consequently, the potential risks for infection of leaf blast and epidemics of sheath blight would increase in rice grown under elevated CO2 concentration.

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Elevated CO2 Concentration Alters Photosynthetic Performances under Fluctuating Light in Arabidopsis thaliana

Cells ◽

10.3390/cells10092329 ◽

2021 ◽

Vol 10 (9) ◽

pp. 2329

Author(s):

Shun-Ling Tan ◽

Xing Huang ◽

Wei-Qi Li ◽

Shi-Bao Zhang ◽

Wei Huang

Keyword(s):

Arabidopsis Thaliana ◽

Elevated Co2 ◽

Co2 Concentration ◽

Atmospheric Co2 ◽

Photochemical Quenching ◽

Elevated Atmospheric Co2 ◽

Actinic Light ◽

Fluctuating Light ◽

Photosynthetic Performances ◽

Atmospheric Co2 Concentrations

In view of the current and expected future rise in atmospheric CO2 concentrations, we examined the effect of elevated CO2 on photoinhibition of photosystem I (PSI) under fluctuating light in Arabidopsis thaliana. At 400 ppm CO2, PSI showed a transient over-reduction within the first 30 s after transition from dark to actinic light. Under the same CO2 conditions, PSI was highly reduced after a transition from low to high light for 20 s. However, such PSI over-reduction greatly decreased when measured in 800 ppm CO2, indicating that elevated atmospheric CO2 facilitates the rapid oxidation of PSI under fluctuating light. Furthermore, after fluctuating light treatment, residual PSI activity was significantly higher in 800 ppm CO2 than in 400 ppm CO2, suggesting that elevated atmospheric CO2 mitigates PSI photoinhibition under fluctuating light. We further demonstrate that elevated CO2 does not affect PSI activity under fluctuating light via changes in non-photochemical quenching or cyclic electron transport, but rather from a rapid electron sink driven by CO2 fixation. Therefore, elevated CO2 mitigates PSI photoinhibition under fluctuating light at the acceptor rather than the donor side. Taken together, these observations indicate that elevated atmospheric CO2 can have large effects on thylakoid reactions under fluctuating light.

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Elevated Atmospheric CO2 Concentration Improved C4 Xero-Halophyte Kochia prostrata Physiological Performance under Saline Conditions

Plants ◽

10.3390/plants10030491 ◽

2021 ◽

Vol 10 (3) ◽

pp. 491

Author(s):

Zulfira Rakhmankulova ◽

Elena Shuyskaya ◽

Kristina Toderich ◽

Pavel Voronin

Keyword(s):

Osmotic Stress ◽

Elevated Co2 ◽

Stress Responses ◽

Dark Respiration ◽

Co2 Concentration ◽

Atmospheric Co2 ◽

Shoot Biomass ◽

Elevated Co2 Concentration ◽

Elevated Atmospheric Co2 ◽

Atmospheric Co2 Concentration

A significant increase in atmospheric CO2 concentration and associated climate aridization and soil salinity are factors affecting the growth, development, productivity, and stress responses of plants. In this study, the effect of ambient (400 ppm) and elevated (800 ppm) CO2 concentrations were evaluated on the C4 xero-halophyte Kochia prostrata treated with moderate salinity (200 mM NaCl) and polyethylene glycol (PEG)-induced osmotic stress. Our results indicated that plants grown at elevated CO2 concentration had different responses to osmotic stress and salinity. The synergistic effect of elevated CO2 and osmotic stress increased proline accumulation, but elevated CO2 did not mitigate the negative effects of osmotic stress on dark respiration intensity and photosystem II (PSII) efficiency. This indicates a stressful state, which is accompanied by a decrease in the efficiency of light reactions of photosynthesis and significant dissipative respiratory losses, thereby resulting in growth inhibition. Plants grown at elevated CO2 concentration and salinity showed high Na+ and proline contents, high water-use efficiency and time required to reach the maximum P700 oxidation level (PSI), and low dark respiration. Maintaining stable water balance, the efficient functioning of cyclic transport of PSI, and the reduction of dissipation costs contributed to an increase in dry shoot biomass (2-fold, compared with salinity at 400 ppm CO2). The obtained experimental data and PCA showed that elevated CO2 concentration improved the physiological parameters of K. prostrata under salinity.

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Growth responses of light demanding and shade tolerant peat swamp forest saplings to elevated CO2

Journal of Environmental Biology ◽

10.22438/jeb/42/3(si)/jeb-01 ◽

2021 ◽

Vol 42 (3(SI)) ◽

pp. 735-743

Author(s):

M.N.L. Wahidah ◽

◽

M.S. Nizam ◽

C.M.Z. Che Radziah ◽

W.A. Wan Juliana ◽

...

Keyword(s):

Growth Rate ◽

Leaf Area ◽

Relative Growth Rate ◽

Elevated Co2 ◽

Co2 Concentration ◽

Growth Responses ◽

Swamp Forest ◽

Relative Growth ◽

Peat Swamp Forest ◽

Elevated Atmospheric Co2

Aim: To determine the growth responses of two peat swamp forest species, Shorea platycarpa, a shade-tolerant slow-growing species and Macaranga pruinosa, a light-demanding fast-growing species under elevated atmospheric CO2 concentration. Methodology: The saplings of both species were grown in a shade house at ambient (400±50 µmol mol-1) and in an open roof ventilation greenhouse at elevated atmospheric CO2 concentration 800±50 µmol mol-1 for seven months. The temperature in both environments ranged between 25-33°C with 55–60% sunlight transmittance and the saplings were thoroughly watered twice a day. Plants growth measurements were estimated at frequent intervals. Saplings biomass characteristics were examined using destructive methods after seven months of treatment and non-destructive method was used for determination of leaf area. Results: Elevated CO2 enhanced all the growth characteristics in M. pruinosa with a significant increase was observed particularly on both height and diameter relative growth rate and biomass characteristics. The height relative growth rate and leaf area were significantly reduced under elevated CO2 in S. platycarpa but did not affect the shoot or root diameter and biomass significantly. A positive correlation (r =0.77, p>0.05) between stem biomass and basal diameter for plants under elevated CO2 was recorded for M. pruinosa, but not in S. platycarpa. Both species showed negative correlation (S. platycarpa; r = -0.53, M. pruinosa; r = -0.46, p>0.05) between stem growth and stem biomass at elevated CO2. Interpretation: These results unveiled profound effects of elevated CO2 on the growth of light-demanding species M. pruinosa, while shade-tolerant species S. platycarpa was not relatively affected by elevated CO2. This underscored the necessity to analyse different species performance to elevated CO2, thereby improving the ability to predict tropical swamp forest ecosystem responses to rising CO2.

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Response of extrafloral nectar production to elevated atmospheric carbon dioxide

Australian Journal of Botany ◽

10.1071/bt18012 ◽

2018 ◽

Vol 66 (7) ◽

pp. 479 ◽

Cited By ~ 1

Author(s):

Belinda Fabian ◽

Brian J. Atwell ◽

Lesley Hughes

Keyword(s):

Elevated Co2 ◽

Atmospheric Carbon Dioxide ◽

Nutrient Balance ◽

Extrafloral Nectar ◽

Nectar Production ◽

Elevated Atmospheric Co2 ◽

Nectar Volume ◽

Cotton Species ◽

Balance Hypothesis ◽

The Impact

Extrafloral nectar attracts ants, whose presence provides protection for the plant against herbivores. Extrafloral nectar is thus a critical component of many plant–insect mutualisms worldwide, so environmental perturbations that alter extrafloral nectar production or composition could be disruptive. The carbon–nutrient balance hypothesis predicts that under elevated CO2 the total volume of extrafloral nectar will increase but the proportion of the foliar carbohydrate pool secreted as extrafloral nectar will decrease, without any change in the sugar composition of the extrafloral nectar. We investigated the impact of elevated atmospheric CO2 on extrafloral nectar in an Australian wild cotton species, Gossypium sturtianum J.H.Willis. Under elevated CO2 there was an increase in the proportion of leaves actively producing nectar and a decrease in the nectar volume per active leaf. Elevated CO2 did not affect the total volume or composition of extrafloral nectar, but there was a change in how the nectar was distributed within the leaf canopy, as well as evidence of increased turnover of leaves and earlier onset of flowering. By the end of the study, there was no difference in the total resources allocated to extrafloral nectar under elevated CO2, which contrasts with the predictions of the carbon-nutrient balance hypothesis. Developmental changes, however, could affect the timing of extrafloral nectar production which could, in turn, alter the foraging patterns of ants and their defence of plants.

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Physiological and Transcriptome Responses to Elevated CO2 Concentration in Populus

Forests ◽

10.3390/f12080980 ◽

2021 ◽

Vol 12 (8) ◽

pp. 980

Author(s):

Tae-Lim Kim ◽

Hoyong Chung ◽

Karpagam Veerappan ◽

Wi Young Lee ◽

Danbe Park ◽

...

Keyword(s):

Elevated Co2 ◽

High Throughput Sequencing ◽

Global Climate ◽

Transcriptome Assembly ◽

Soluble Sugar ◽

Model Organism ◽

Co2 Concentration ◽

Total Soluble Sugar ◽

Elevated Atmospheric Co2 ◽

Co2 Concentrations

Global climate change is heavily affected by an increase in CO2. As one of several efforts to cope with this, research on poplar, a representative, fast growing, and model organism in plants, is actively underway. The effects of elevated atmospheric CO2 on the metabolism, growth, and transcriptome of poplar were investigated to predict productivity in an environment where CO2 concentrations are increasing. Poplar trees were grown at ambient (400 ppm) or elevated CO2 concentrations (1.4× ambient, 560 ppm, and 1.8× ambient, 720 ppm) for 16 weeks in open-top chambers (OTCs). We analyzed the differences in the transcriptomes of Populusalba × Populus glandulosa clone “Clivus” and Populus euramericana clone “I-476” using high-throughput sequencing techniques and elucidated the functions of the differentially expressed genes (DEGs) using various functional annotation methods. About 272,355 contigs and 207,063 unigenes were obtained from transcriptome assembly with the Trinity assembly package. Common DEGs were identified which were consistently regulated in both the elevated CO2 concentrations. In Clivus 29, common DEGs were found, and most of these correspond to cell wall proteins, especially hydroxyproline-rich glycoproteins (HRGP), or related to fatty acid metabolism. Concomitantly, in I-476, 25 were identified, and they were related to heat shock protein (HSP) chaperone family, photosynthesis, nitrogen metabolism, and carbon metabolism. In addition, carbohydrate contents, including starch and total soluble sugar, were significantly increased in response to elevated CO2. These data should be useful for future gene discovery, molecular studies, and tree improvement strategies for the upcoming increased-CO2 environments.

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Effect of Different Climate Change Variables on the Ecology and Management of Sesbania cannabina through Glyphosate

Plants ◽

10.3390/plants10050910 ◽

2021 ◽

Vol 10 (5) ◽

pp. 910

Author(s):

Nadeem Iqbal ◽

Sudheesh Manalil ◽

Bhagirath Singh Chauhan ◽

Steve Adkins

Keyword(s):

Climate Change ◽

Soil Moisture ◽

Elevated Co2 ◽

Atmospheric Carbon Dioxide ◽

Growth Index ◽

Field Capacity ◽

Co2 Concentration ◽

Climate Change Scenarios ◽

Sesbania Cannabina ◽

Co2 Concentrations

An elevated atmospheric carbon dioxide (CO2) concentration and frequent droughts are two anticipated climate change scenarios in which certain invasive weeds may develop competitive advantages over crops and adversely impact productivity and herbicide efficacy. Hence, a study was conducted to explore the effect of different climatic scenarios on the growth and management of Sesbania cannabina (Retz.) Pers with glyphosate. The variables investigated were two CO2 concentrations (400 and 700 ppm), two soil moisture levels (100% and 50% of field capacity (FC)), and three glyphosate rates (0 (control), 517 (50% of recommended rate), and 1034 g ae ha−1 (recommended rate)). CO2 concentrations and soil moisture levels had different effects on the growth and management of S. cannabina. Overall, 100% FC and elevated [CO2] of 700 ppm recorded the maximum plant height (38 cm), leaves per plant (20), growth index (60), chlorophyll content (SPAD value 37), and dry biomass (3 g) in comparison with ambient [CO2] of 400 ppm and 50% FC treatment. The recommended glyphosate application gave 100% weed biomass reduction; however, efficacy was reduced (63%) when applied at 50% of the recommended rate under elevated [CO2] of 700 ppm and 50% FC conditions.

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Study of physiological responses of Allium sativum to elevated CO2 and temperature

Journal of Environmental Biology ◽

10.22438/jeb/42/5/mrn-1687 ◽

2021 ◽

Vol 42 (5) ◽

pp. 1289-1297

Author(s):

N. Rahman ◽

◽

R. Das ◽

B.D. Narzary ◽

D.B. Phookan ◽

...

Keyword(s):

Carbon Dioxide ◽

Temperature Gradient ◽

Elevated Co2 ◽

Allium Sativum ◽

Physiological Responses ◽

Co2 Concentration ◽

Climatic Conditions ◽

Temperature Regimes ◽

Elevated Co2 And Temperature ◽

Ambient Co2

Aim: The present investigation was undertaken to study the response of some garlic varieties of Allium sativum under different ambient and elevated CO2 and temperature conditions in order to investigate the physiological responses under changing climatic condition. Methodology: A two factorial CRD experiment was conducted for two years with four varieties of Allium sativum (Ekfutia Assam, Assam Local, Bhima Omkar and Bhima Purple) under four atmospheric regimes [T1= Ambient CO2 and temperature; T2= Carbon dioxide Temperature Gradient Tunnel-I (400 ppm CO2 + 2oC higher than ambient); T3 = Carbon dioxide Temperature Gradient Tunnel-II (550 ppm CO2 + 4oC higher than ambient); T4 = Carbon dioxide Temperature Gradient Tunnel-III (700 ppm CO2 + 6oC higher than ambient)]. Major changes in physiological parameters of the varieties were recorded in Carbon dioxide Temperature Gradient Tunnel-II as compared to ambient condition. The rate of photosynthesis was measured on fully expanded youngest leaves of each sample plant using a portable Infrared Gas Analyzer. Results: The mean photosynthetic rate of all four varieties grown over two years was 13.43% higher in Carbon dioxide Temperature Gradient Tunnel-II over varieties grown for two consecutive years under Ambient CO2 and temperature. However, high CO2 concentration and temperature stress significantly reduced the stomatal conductance approximately by 27.48%. Interpretation: The results of this study gives a comprehensive analysis of garlic varieties under four different climatic conditions of CO2 and temperature and revealed that Ekfutia Assam and Assam Local and garlic varieties Bhima Omkar and Bhima Purple were promising varieties as they responded significantly to elevated CO2 and temperature regimes. This may provide some critical inputs for optimizing the strategies in future farming and farming opportunities of this commercially and medicinally important crop under changing climatic conditions.

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