Growth Responses on Young Wheat Plants to a Range of Ambient CO2 Levels

1978 ◽  
Vol 5 (1) ◽  
pp. 45 ◽  
Author(s):  
TF Neales ◽  
AO Nicholls
Keyword(s):  
Plant Biomass ◽  
Growth Parameters ◽  
Co2 Enrichment ◽  
Co2 Concentration ◽  
Plant Age ◽  
Growth Responses ◽  
Wheat Seedlings ◽  
Co2 Levels ◽  
Sequential Experiments ◽  
Ambient Co2

The growth of wheat seedlings in a closed environment was measured from day 10 to day 24 after germination, in 12 separate and sequential experiments, in which the imposed variable was the ambient CO2 concentration. CO2 levels between 200 and 800 volumes per million (vpm) and a daily irradiance of 6.5 MJ m-2 were used. The effects of CO2 concentration on various growth parameters strongly interacted with plant age. For instance, in the 10-day-old plants, relative growth rate and net assimilation rate were increased (by 35 and 55% respectively) by an increase in CO2 levels from 200 to 800 vpm, whereas these two growth parameters were reduced (by 44 and 16%) in 24-day-old plants over the same interval of CO2 concentration. Also, increasing CO2 levels reduced the leafiness (leaf area ratio) of the plant, and increased the dry matter in the leaves (specific leaf weight). It is suggested that the observed large interactions on plant growth of plant age and CO2 concentration account for the relatively small enhancement by CO2 enrichment of total plant biomass and economic yield that are reported in the literature.

scholarly journals Differential Growth Responses of Wheat Seedlings to Elevated CO2

2018 ◽  
Vol 10 (3) ◽  
pp. 400-409 ◽  
Author(s):  
Hamid Reza ESHGHIZADEH ◽  
Morteza ZAHEDI ◽  
Samaneh MOHAMMADI
Keyword(s):  
Leaf Area ◽  
Plant Height ◽  
Elevated Co2 ◽  
Co2 Concentration ◽  
Tolerance Index ◽  
Dry Matter Accumulation ◽  
Wheat Cultivars ◽  
Growth Responses ◽  
Differential Growth ◽  
Wheat Seedlings

Intraspecific variations in wheat growth responses to elevated CO2 was evaluated using 20 Iranian bread wheat (Triticum aestivum L.) cultivars. The plants were grown in the modified Hoagland nutrient solution at a greenhouse until 35 days of age using two levels of CO2 (~380 and 700 µmol mol–1). The shoot and root dry weights of the wheat cultivars exhibited average enhancements of 17% and 36%, respectively, under elevated CO2. This increase was associated with higher levels of chlorophyll a (25%), chlorophyll b (21%), carotenoid (30%), leaf area (54%) and plant height (49.9%). The leaf area (r = 0.69**), shoot N content (r = 0.62**), plant height (r = 0.60**) and root volume (r = 0.53*) were found to have important roles in dry matter accumulation of tested wheat cultivars under elevated CO2 concentration. However, responses to elevated CO2 were considerably cultivar-dependent. Based on the stress susceptibility index (SSI) and stress tolerance index (STI), the wheat cultivars exhibiting the best response to elevated CO2 content were ‘Sistan’, ‘Navid’, ‘Shiraz’, ‘Sepahan’ and ‘Bahar’, while the ones with poor responses were ‘Omid’, ‘Marun’, ‘Sorkhtokhm’ and ‘Tajan’. The findings from the present experiment showed significant variation among the Iranian wheat cultivars in terms of their responses to elevated air CO2, providing the opportunity to select the most efficient ones for breeding purposes.

scholarly journals Biostimulant Effects of an Aqueous Extract of Duckweed (Lemna minor L.) on Physiological and Biochemical Traits in the Olive Tree

Agriculture ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1299
Author(s):  
Luca Regni ◽  
Daniele Del Buono ◽  
Begoña Miras-Moreno ◽  
Biancamaria Senizza ◽  
Luigi Lucini ◽  
...  
Keyword(s):  
Chlorophyll Content ◽  
Aqueous Extract ◽  
Plant Biomass ◽  
Growth Parameters ◽  
Lemna Minor ◽  
Net Photosynthesis ◽  
Dry Weight ◽  
Co2 Concentration ◽  
Olive Tree ◽  
Water Volume

Biostimulants are becoming increasingly popular in agriculture for their ability to induce beneficial effects in crops, paving the way towards the identification of new materials with biostimulant potential. This study evaluated the potential of different concentrations of an aqueous extract (0.25%, 0.50%, and 1.00%, dry weight/water volume, respectively) obtained from duckweed (Lemna minor L.) to stimulate olive plants. Leaf net photosynthesis (Pn), leaf transpiration rate (E), stomatal conductance (gs), sub-stomatal CO2 concentration (Ci), chlorophyll content and other plant growth parameters were investigated. As a result, the extract improved Pn, gs, Ci, chlorophyll content and plant biomass production (leaf fresh and dry weight). Furthermore, the duckweed extract generally increased the uptake of nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe) and zinc (Zn), while it did not influence the content of sodium (Na), manganese (Mn) and copper (Cu). The untargeted metabolomic profiling of the extract revealed the presence of signalling compounds (including phytohormones), phenolics and glutathione. Such broad diversity of bioactives may support the stimulatory potential observed in olive. In summary, this study revealed for the first time that duckweed could be seen as a promising species to obtain extracts with biostimulant properties in olive trees.

scholarly journals Growth and physiological potential of Terminalia arjuna under elevated CO2 levels in Open top chamber condition

2021 ◽  
Vol 13 (3) ◽  
pp. 1121-1126
Author(s):  
Kamla Dhyani ◽  
Hind Bhushan Kuniyal ◽  
Hukum Singh ◽  
Sobha
Keyword(s):  
Elevated Co2 ◽  
Growth Parameters ◽  
Vapour Pressure Deficit ◽  
Co2 Concentration ◽  
Climatic Conditions ◽  
Terminalia Arjuna ◽  
Percentage Increase ◽  
Ambient Conditions ◽  
Co2 Levels ◽  
Collar Diameter

Terminalia arjuna is native to India and occurs naturally along the banks of streams and rivers. The species is characterized to dry deciduous forests. The present study was carried out for the growth and physiological changes of T. arjuna in different elevated CO2 levels. Open top chambers were used to expose plants to ambient and elevated CO2 concentrations (400 and 800 ppm). The experiment was conducted in the month of March to August in 2019 for six months. The results showed that the growth parameters, i.e. plant height, collar diameter, the number of leaves, were found to be increased in elevated CO2 conditions. The percentage increase in physiological parameters like photosynthetic rate (28.82), mesophyll efficiency (60 % more in elevated CO2 condition), CO2 concentration (55 % more in elevated CO2), vapour pressure deficit (4.83 at 800 ppm) and water use efficiency (5.94 at ppm)  increased. In contrast, transpiration rate (5.38 at 800 ppm and 10.11 ppm at ambient condition) and stomatal conductance (30% less in 800 ppm) decreased under elevated CO2 compared to ambient conditions. The study concluded that changing climatic conditions and significantly elevated CO2 in future may profoundly influence plant growth and the physiological response of T. arjuna.

scholarly journals Effects of ocean acidification on pelagic carbon fluxes in a mesocosm experiment

2016 ◽  
Vol 13 (21) ◽  
pp. 6081-6093 ◽  
Author(s):  
Kristian Spilling ◽  
Kai G. Schulz ◽  
Allanah J. Paul ◽  
Tim Boxhammer ◽  
Eric P. Achterberg ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Primary Production ◽  
Ocean Acidification ◽  
Bacterial Production ◽  
Co2 Concentration ◽  
Carbon Fluxes ◽  
Co2 Levels ◽  
Standing Stocks ◽  
Co2 Treatment ◽  
Ambient Co2

Abstract. About a quarter of anthropogenic CO2 emissions are currently taken up by the oceans, decreasing seawater pH. We performed a mesocosm experiment in the Baltic Sea in order to investigate the consequences of increasing CO2 levels on pelagic carbon fluxes. A gradient of different CO2 scenarios, ranging from ambient ( ∼  370 µatm) to high ( ∼  1200 µatm), were set up in mesocosm bags ( ∼  55 m3). We determined standing stocks and temporal changes of total particulate carbon (TPC), dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and particulate organic carbon (POC) of specific plankton groups. We also measured carbon flux via CO2 exchange with the atmosphere and sedimentation (export), and biological rate measurements of primary production, bacterial production, and total respiration. The experiment lasted for 44 days and was divided into three different phases (I: t0–t16; II: t17–t30; III: t31–t43). Pools of TPC, DOC, and DIC were approximately 420, 7200, and 25 200 mmol C m−2 at the start of the experiment, and the initial CO2 additions increased the DIC pool by  ∼  7 % in the highest CO2 treatment. Overall, there was a decrease in TPC and increase of DOC over the course of the experiment. The decrease in TPC was lower, and increase in DOC higher, in treatments with added CO2. During phase I the estimated gross primary production (GPP) was  ∼  100 mmol C m−2 day−1, from which 75–95 % was respired,  ∼  1 % ended up in the TPC (including export), and 5–25 % was added to the DOC pool. During phase II, the respiration loss increased to  ∼  100 % of GPP at the ambient CO2 concentration, whereas respiration was lower (85–95 % of GPP) in the highest CO2 treatment. Bacterial production was  ∼  30 % lower, on average, at the highest CO2 concentration than in the controls during phases II and III. This resulted in a higher accumulation of DOC and lower reduction in the TPC pool in the elevated CO2 treatments at the end of phase II extending throughout phase III. The “extra” organic carbon at high CO2 remained fixed in an increasing biomass of small-sized plankton and in the DOC pool, and did not transfer into large, sinking aggregates. Our results revealed a clear effect of increasing CO2 on the carbon budget and mineralization, in particular under nutrient limited conditions. Lower carbon loss processes (respiration and bacterial remineralization) at elevated CO2 levels resulted in higher TPC and DOC pools than ambient CO2 concentration. These results highlight the importance of addressing not only net changes in carbon standing stocks but also carbon fluxes and budgets to better disentangle the effects of ocean acidification.

scholarly journals Effect of water addition and nitrogen fertilization on the fluxes of CH<sub>4</sub>, CO<sub>2</sub>, NO<sub>x</sub>, and N<sub>2</sub>O following five years of elevated CO<sub>2</sub> in the Colorado Shortgrass Steppe

2003 ◽  
Vol 3 (5) ◽  
pp. 1703-1708 ◽  
Author(s):  
A. R. Mosier ◽  
E. Pendall ◽  
J. A. Morgan
Keyword(s):  
Elevated Co2 ◽  
Plant Biomass ◽  
Co2 Enrichment ◽  
Surface Fluxes ◽  
Shortgrass Steppe ◽  
Water Addition ◽  
No Emission ◽  
Ch4 Uptake ◽  
N2o Fluxes ◽  
Ambient Co2

Abstract. An open-top-chamber (OTC) CO2 enrichment (~720 mmol mol-1) study was conducted in the Colorado shortgrass steppe from April 1997 through October 2001. Aboveground plant biomass increased under elevated CO2 and soil moisture content was typically higher than under ambient CO2 conditions. Fluxes of CH4, CO2, NOx and N2O, measured weekly year round were not significantly altered by CO2 enrichment over the 55 month period of observation. During early summer of 2002, following the removal of the open-top-chambers from the CO2 enrichment sites in October 2001, we conducted a short term study to determine if soil microbial processes were altered in soils that had been exposed to double ambient CO2 concentrations during the growing season for the past five years. Microplots were established within each experimental site and 10 mm of water or 10 mm of water containing the equivalent of 10 g m-2 of ammonium nitrate-N was applied to the soil surface. Fluxes of CO2, CH4, NOx and N2O fluxes within control (unchambered), ambient CO2 and elevated CO2 OTC soils were measured at one to three day intervals for the next month. With water addition alone, CO2 and NO emission did not differ between ambient and elevated CO2 soils, while CH4 uptake rates were higher and N2O fluxes lower in elevated CO2 soils. Adding water and mineral N resulted in increased CO2 emissions, increased CH4 uptake and decreased NO emissions in elevated CO2 soils. The N addition study confirmed previous observations that soil respiration is enhanced under elevated CO2 and N immobilization is increased, thereby decreasing NO emission.

scholarly journals Effects of ocean acidification on pelagic carbon fluxes in a mesocosm experiment

2016 ◽  
Author(s):  
Kristian Spilling ◽  
Kai G. Schulz ◽  
Allanah J. Paul ◽  
Tim Boxhammer ◽  
Eric P. Achterberg ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Primary Production ◽  
Ocean Acidification ◽  
Bacterial Production ◽  
Co2 Concentration ◽  
Carbon Fluxes ◽  
Co2 Levels ◽  
Standing Stocks ◽  
Co2 Treatment ◽  
Ambient Co2

Abstract. About a quarter of anthropogenic CO2 emissions are currently taken up by the oceans decreasing seawater pH. We performed a mesocosm experiment in the Baltic Sea in order to investigate the consequences of increasing CO2 levels on pelagic carbon fluxes. A gradient of different CO2 scenarios, ranging from ambient (~ 370 µatm) to high (~ 1200 µatm), were set up in mesocosm bags (~ 55 m3). We determined standing stocks and temporal changes of total particulate carbon (TPC), dissolved organic (DOC), dissolved inorganic (DIC) and particulate organic carbon (POC) of specific plankton groups. We also measured carbon flux via CO2 exchange with the atmosphere and sedimentation (export); and biological rate measurements of primary production, bacterial production and total respiration. The experiment lasted for 44 days and was divided into three different phases (I: t0–t16; II: t17–t30; III: t31–t43). Pools of TPC, DOC and DIC were approximately 420, 7200 and 25 200 mmol C m−2 at the start of the experiment, and the initial CO2 additions increased the DIC pool by ~ 7 % in the highest CO2 treatment. Overall, there was a decrease in TPC and increase of DOC over the course of the experiment. The decrease in TPC was lower, and increase in DOC higher, in treatments with added CO2. During Phase I the estimated gross primary production (GPP) was ~ 100 mmol C fixed m−2 d−1; from which 75–95 % were respired, ~ 1 % ended up in the TPC (including export) and 5–25 % added to the DOC pool. During Phase II, the respiration loss increased to ~ 100 % of GPP at the ambient CO2 concentration, whereas respiration was lower (85–95 % of GPP) in the highest CO2 treatment. Bacterial production was ~ 30 % lower, on average, at the highest CO2 concentration compared with the controls during Phases II and III. This resulted in a higher accumulation DOC standing stock and lower reduction in TPC in the elevated CO2 treatments at the end of Phase II extending throughout Phase III. The "extra" organic carbon at high CO2 remained fixed in an increasing biomass of small-sized plankton and in the DOC pool, and did not transferred into large, sinking aggregates. Our results revealed a clear effect of increasing CO2 on carbon production and mineralization, in particular under nutrient limited conditions. Lower carbon loss processes (respiration and bacterial remineralization) at elevated CO2 levels resulted in higher TPC and DOC pools compared with the ambient CO2 concentration. These results highlight the importance to address not only net changes in carbon standing stocks, but also carbon fluxes and budgets to better disentangle the effects of ocean acidification.

scholarly journals Elevated field atmospheric CO2 concentrations affect the characteristics of winter wheat (cv. Bologna) grains

2017 ◽  
Vol 68 (8) ◽  
pp. 713 ◽  
Author(s):  
Francesca Verrillo ◽  
Franz-Werner Badeck ◽  
Valeria Terzi ◽  
Fulvia Rizza ◽  
Letizia Bernardo ◽  
...  
Keyword(s):  
Co2 Enrichment ◽  
Co2 Concentration ◽  
Triticum Aestivum L ◽  
Interactive Effects ◽  
Elevated Concentration ◽  
Co2 Concentrations ◽  
Co2 Levels ◽  
Carbon Dioxide Co2 ◽  
Atmospheric Co2 Concentrations ◽  
The Impact

The aim of this study was to investigate the impact of elevated concentration of carbon dioxide (CO2), as expected over coming decades, on yield and quality of winter bread wheat (Triticum aestivum L.). Plants (cv. Bologna) were grown by using the free-air CO2 enrichment (FACE) system at Fiorenzuola d’Arda under ambient (control) and elevated (570 ppm, e[CO2]) CO2 concentrations for two growing seasons. We addressed whether there would be a response of wheat grains to elevated CO2 concentration in terms of the contents of nitrogen (N), micro- and macronutrients, proteins and free amino acids. Under e[CO2], total wheat biomass and grain yield increased in both years of the study. Grain N percentage was reduced under e[CO2], but grain N yield (kg ha–1) was increased. Among macro- and micronutrients, a decrease in zinc concentration was observed. The proteome pattern was significantly different in grains grown at the two different CO2 levels, but the observed changes were highly dependent on interactions with prevailing environmental conditions. Finally, a negative trend was observed in the early germination rates of seeds from plants grown under e[CO2] compared with the controls. The results suggest that the expected increase in CO2 levels and their interactive effects with environmental variables may influence agronomic performance by increasing yield and negatively affecting quality.

scholarly journals A Meta-Analytical Approach on Arbuscular Mycorrhizal Fungi Inoculation Efficiency on Plant Growth and Nutrient Uptake

Agriculture ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 370
Author(s):  
Murugesan Chandrasekaran
Keyword(s):  
Plant Growth ◽  
Arbuscular Mycorrhizal Fungi ◽  
Nutrient Uptake ◽  
Mycorrhizal Fungi ◽  
Host Plants ◽  
Plant Biomass ◽  
Meta Analysis ◽  
Arbuscular Mycorrhizal ◽  
Growth Responses ◽  
Mycorrhizal Plants

Arbuscular mycorrhizal fungi (AMF) are obligate symbionts of higher plants which increase the growth and nutrient uptake of host plants. The primary objective was initiated based on analyzing the enormity of optimal effects upon AMF inoculation in a comparative bias between mycorrhizal and non-mycorrhizal plants stipulated on plant biomass and nutrient uptake. Consequently, in accomplishing the above-mentioned objective a vast literature was collected, analyzed, and evaluated to establish a weighted meta-analysis irrespective of AMF species, plant species, family and functional group, and experimental conditions in the context of beneficial effects of AMF. I found a significant increase in the shoot, root, and total biomass by 36.3%, 28.5%, and, 29.7%, respectively. Moreover, mycorrhizal plants significantly increased phosphorus, nitrogen, and potassium uptake by 36.3%, 22.1%, and 18.5%, respectively. Affirmatively upon cross-verification studies, plant growth parameters intensification was accredited to AMF (Rhizophagus fasciculatus followed by Funniliforme mosseae), plants (Triticum aestivum followed by Solanum lycopersicum), and plant functional groups (dicot, herbs, and perennial) were the additional vital important significant predictor variables of plant growth responses. Therefore, the meta-analysis concluded that the emancipated prominent root characteristics, increased morphological traits that eventually help the host plants for efficient phosphorus uptake, thereby enhancing plant biomass. The present analysis can be rationalized for any plant stress and assessment of any microbial agent that contributes to plant growth promotion.

Sign in / Sign up

Export Citation Format

Share Document