Photosynthetic response to growth temperature and CO2 enrichment in two species of C4 grasses

1985 ◽  
Vol 63 (3) ◽  
pp. 483-487 ◽  
Author(s):  
Catherine Potvin ◽  
Boyd R. Strain
Keyword(s):  
North Carolina ◽  
Growth Temperature ◽  
Dark Respiration ◽  
Co2 Enrichment ◽  
Net Photosynthesis ◽  
C4 Grasses ◽  
Eleusine Indica ◽  
Respiration Rates ◽  
Acclimation Potential ◽  
Photosynthesis And Respiration

Plants of Echinochloa crus-galli from Québec, North Carolina, and Mississippi and of Eleusine indica from Mississippi were grown under three thermoperiods (28:22, 24:18, 21:15 °C) and two atmospheric CO2 concentrations (350 and 675 μL ∙ L−1). CO2 enrichment induced an increase in net photosynthesis and in dark respiration for all populations. Neither conductance, transpiration, nor the transpiration/photosynthesis ratio were affected by CO2 enrichment. Plants showed higher photosynthetic and dark respiration rates when grown in warm regimes. Stomatal conductance did not vary with growth temperature. Cool-adapted plants from Québec maintained the overall highest net photosynthesis and respiration. Plants originating from warm areas had a weaker acclimation potential to low temperature than those from cool environments.

Effects of pCO2 on photosynthesis and respiration of tropical scleractinian corals and calcified algae

2016 ◽  
Vol 74 (4) ◽  
pp. 1092-1102 ◽  
Author(s):  
S. Comeau ◽  
R. C. Carpenter ◽  
P. J. Edmunds
Keyword(s):  
Dark Respiration ◽  
Net Photosynthesis ◽  
French Polynesia ◽  
Published Data ◽  
Experimental Conditions ◽  
Gross Photosynthesis ◽  
Functional Relationships ◽  
Respiration Rates ◽  
Photosynthesis And Respiration

The effects of ocean acidification (OA) on coral reefs have been studied thoroughly with a focus on the response of calcification of corals and calcified algae. However, there are still large gaps in our knowledge of the effects of OA on photosynthesis and respiration of these organisms. Comparisons among species and determination of the functional relationships between pCO2 and either photosynthesis or respiration are difficult using previously published data, because experimental conditions typically vary widely between studies. Here, we tested the response of net photosynthesis, gross photosynthesis, dark respiration, and light-enhanced dark respiration (LEDR) of eight coral taxa and seven calcified alga taxa to six different pCO2 levels (from 280 to 2000 µatm). Organisms were maintained during 7–10 days incubations in identical conditions of light, temperature, and pCO2 to facilitate comparisons among species. Net photosynthesis was not affected by pCO2 in seven of eight corals or any of the algae; gross photosynthesis did not respond to pCO2 in six coral taxa and six algal taxa; dark respiration also was unaffected by pCO2 in six coral and six algae; and LEDR did not respond to pCO2 in any of the tested species. Overall, our results show that pCO2 levels up to 2000 µatm likely will not fertilize photosynthesis or modify respiration rates of most of the main calcifiers on the back reef of Moorea, French Polynesia.

Thermal acclimation of respiration but not photosynthesis in Pinus radiata

2008 ◽  
Vol 35 (6) ◽  
pp. 448 ◽  
Author(s):  
Lai Fern Ow ◽  
David Whitehead ◽  
Adrian S. Walcroft ◽  
Matthew H. Turnbull
Keyword(s):  
Pinus Radiata ◽  
Growth Temperature ◽  
Dark Respiration ◽  
Temperature Acclimation ◽  
Short Term ◽  
Photosynthesis And Respiration ◽  
Term Response ◽  
N Status ◽  
Respiratory Responses

Pinus radiata L. were grown in climate-controlled cabinets under three night/day temperature treatments, and transferred between treatments to mimic changes in growth temperature. The objective was to determine the extent to which dark respiration and photosynthesis in pre-existing and new needles acclimate to changes in growth temperatures. We also assessed whether needle nitrogen influenced the potential for photosynthetic and respiratory acclimation, and further assessed if short-term (instantaneous, measured over a few hours) respiratory responses are accurate predictors of long-term (acclimated, achieved in days–weeks) responses of respiration to changing temperature. Results show that respiration displayed considerable potential for acclimation. Cold and warm transfers resulted in some acclimation of respiration in pre-existing needles, but full acclimation was displayed only in new needles formed at the new growth temperature. Short-term respiratory responses were poor predictors of the long-term response of respiration due to acclimation. There was no evidence that photosynthesis in pre-existing or new needles acclimated to changes in growth temperature. N status of leaves had little impact on the extent of acclimation. Collectively, our results indicate that there is little likelihood that respiration would be significantly stimulated in this species as night temperatures increase over the range of 10–20°C, but that inclusion of temperature acclimation of respiration would in fact lead to a shift in the balance between photosynthesis and respiration in favour of carbon uptake.

Photosynthesis and respiration decline with light intensity in dominant and suppressed Eucalyptus globulus canopies

2008 ◽  
Vol 35 (6) ◽  
pp. 439 ◽  
Author(s):  
A. P. O'Grady ◽  
D. Worledge ◽  
A. Wilkinson ◽  
M. Battaglia
Keyword(s):  
Eucalyptus Globulus ◽  
Dark Respiration ◽  
Light Availability ◽  
Structural Complexity ◽  
Leaf Nitrogen ◽  
Leaf Nitrogen Content ◽  
Area Index ◽  
Respiration Rates ◽  
Leaf Dark Respiration ◽  
Photosynthesis And Respiration

Within canopy gradients in light-saturated photosynthesis (Amax), foliar nitrogen ([N]area) and leaf dark respiration (R15) were studied in the canopies of dominant and suppressed trees within an even-aged (4-year-old) Eucalyptus globulus (Labill) stand in southern Tasmania. Despite being an even-aged stand growing in a relatively uniform environment with respect to nutrient and water availability, the stand exhibited considerable structural complexity. Diameter at 1.3 m ranged between 3 cm and 21 cm, trees average 12 m height and stand leaf area index was ~6 m2 m–2 leading to strong gradients in light availability. We were interested in understanding the processes governing canopy production in trees of contrasting dominance classes. Vertical gradients in photosynthesis and foliar respiration were studied within the canopies of dominant and suppressed trees during 2006 and 2007. Amax varied from ~18 μmol m–2 s–1 in the upper canopy to 3 μmol m–2 s–1 at lower canopy positions. On average, Amax were higher in the dominant trees than in the suppressed trees. However, at any given height, Amax were similar in suppressed and dominant trees and were strongly related to leaf nitrogen content. Dark respiration varied from ~1.4 μmol m–2 s–1 in the upper canopy to 0.2 μmol m–2 s–1 in the lower canopy positions. In contrast to the patterns for Amax, dark respiration rates in the suppressed trees were higher than dominant trees at similar canopy positions. Respiration rates were also strongly related to [N]area and to Amax.

Temperature relations of gas exchange in altitudinal populations of Taraxacum officinale

1977 ◽  
Vol 55 (19) ◽  
pp. 2496-2502 ◽  
Author(s):  
Paul R. Kemp ◽  
George J. Williams III ◽  
David S. May
Keyword(s):  
Gas Exchange ◽  
Dark Respiration ◽  
Net Photosynthesis ◽  
Taraxacum Officinale ◽  
Verbascum Thapsus ◽  
Respiration Rates ◽  
Hill Activity ◽  
Population Origin ◽  
Weedy Species ◽  
Temperature Responses

Taraxacum officinale plants representative of three altitudinally diverse populations were grown under uniform conditions. Temperature responses of net photosynthesis, photorespiration, and transpiration were obtained from four plants of each population over the range of 10 to 40 °C at saturating irradiances(1000 μE ∙ m−2 ∙ s−1). Dark respiration rates were obtained from the same plants over the range of 10 to 30 °C. All plants exhibited similar gas exchange responses to temperature regardless of population origin. Maximum rates of net photosynthesis occurred near 20 °C in all plants and averaged 20.8 mg CO2 ∙ dm−2 ∙ h−1 (mean of 12 plants). Dark respiration and photorespiration rates increased nearly linearly with temperature in all plants. These results are in contrast with previous studies of the same populations in which differences in Hill activity and succinate dehydrogenase activity were reported. However, the photosynthetic patterns and lack of genetic differentiation of photosynthesis are similar to the results obtained for another weedy species, Verbascum thapsus, along the same altitudinal transect.

Thermal acclimation of photosynthesis by the arctic plant Saxifraga cernua

1986 ◽  
Vol 64 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Bruce T. Mawson ◽  
Josef Svoboda ◽  
Raymond W. Cummins
Keyword(s):  
Low Temperature ◽  
Growth Temperature ◽  
Dark Respiration ◽  
Photosynthetic Apparatus ◽  
Net Photosynthesis ◽  
Temperature Acclimation ◽  
The Arctic ◽  
Optimum Temperature ◽  
Whole Plants ◽  
Saxifraga Cernua

The thermal acclimations of net photosynthesis, dark respiration, and photorespiration have been studied in the arctic plant Saxifraga cernua. The gas exchange of whole plants grown to maturity under different temperature regimes was analysed for individual plants transferred from (i) 10 to 20 (referred to as high-temperature acclimation) and (ii) 20 to 5 °C (low-temperature acclimation). High- and low-temperature acclimation resulted in shifts of the leaf temperature optimum for net photosynthesis of whole plants in the direction of the new growth temperature. That the acclimating temperature directly affected the photosynthetic apparatus was indicated by (i) changes in the optimum temperature for gross photosynthesis of whole plants and (ii) a change in the oxygen sensitivity of net photosynthesis after acclimation to a new growth temperature. The change in the optimum temperature for net photosynthesis was also due, in part, to altered dark respiration rates which increased during acclimation to low growth temperatures. These results suggest that such acclimation in arctic species like S. cernua arose as a result of the selective pressure of fluctuating temperatures which are experienced during the growth season to maximize annual growth under arctic and subarctic conditions.

EFFECTS OF GREENHOUSE CO2 ENRICHMENT ON THE YIELD AND PHOTOSYNTHETIC PHYSIOLOGY OF TOMATO PLANTS

1978 ◽  
Vol 58 (3) ◽  
pp. 801-817 ◽  
Author(s):  
PETER R. HICKLENTON ◽  
PETER A. JOLLIFFE
Keyword(s):  
Dark Respiration ◽  
Co2 Enrichment ◽  
Stomatal Resistance ◽  
Tomato Plants ◽  
Behavioral Indices ◽  
Respiration Rates ◽  
Growth Regime ◽  
Photosynthetic Physiology ◽  
Marketable Fruit ◽  
Mesophyll Resistance

Tomato crops were grown in greenhouses with and without CO2 enrichment to approximately 900 vpm. Plants grown under enhanced CO2 concentrations flowered earlier and produced 30% more marketable fruit than those grown in normal air. Measurements were conducted on CO2 and water vapor exchanges in apical and basal leaves under a range of irradiances and CO2 concentrations. Photosynthesis rates were higher in leaves from the enriched regime at test irradiances above 50 μE m−2 s−1 (400–700 nm). Increasing test CO2 concentration enlarged that difference, with the effect being most pronounced in apical leaves. Mesophyll resistance to CO2 assimilation was greater than stomatal resistance at all irradiances, and tended to be higher in basal leaves than in apical leaves of the CO2-enriched plants. Stomatal resistances were similar in apical and basal leaves from CO2-enriched plants. In unenriched plants, however, stomatal resistances were lower in apical than in basal leaves. CO2 compensation points were decreased in leaves developed under CO2 enrichment, but dark respiration rates were not significantly affected by growth regime. Behavioral indices of photosynthesis indicated that the efficiency of CO2 utilization was improved by growth in a CO2-enriched regime. Such fundamental changes in photosynthetic behavior suggest that the effects of CO2 enrichment on yield are not only due to increased growth in the presence of additional photosynthetic substrate. They also result from changes in the innate capacity of photosynthetic systems to utilize CO2.

Studies on lichen-dominated systems. XIV. The comparative ecology of Alectoria nitidula and Cladina alpestris

1975 ◽  
Vol 53 (22) ◽  
pp. 2608-2613 ◽  
Author(s):  
K. A. Kershaw
Keyword(s):  
Net Photosynthesis ◽  
The Other ◽  
Beach Ridge ◽  
Temperature Optimum ◽  
Comparative Ecology ◽  
Respiration Rates ◽  
Photosynthesis And Respiration

The response of net photosynthesis and respiration in Cladina alpestris and Alectoria nitidula, at 0 and 150 μeinsteins m−2 s−1, 5, 10, 15, 20, 25, and 30 °C, and at all thallus moisture levels, is described. The two species have markedly contrasting responses, which correlates very well with their ecology at East Pen Island. Cladina alpestris is shown to occur in two physiological forms: one is restricted to beach ridge summits and the other is restricted to the lower slopes. The physiology of these two forms adapts them to either the cool, dry, ridge crests or the warmer, moister, ridge slopes. Marked acclimation of the temperature optimum of net photosynthesis in Alectoria nitidula is shown to occur between August and December. This is an acclimation of the photosynthetic mechanism of the algal component since respiration rates remain constant. Alectoria nitidula is shown to further acclimate to warm temperatures under air-dried conditions in the laboratory.

Effects of CO2 enrichment and temperature on growth in two C4 weeds, Echinochloa crus-galli and Eleusine indica

1985 ◽  
Vol 63 (9) ◽  
pp. 1495-1499 ◽  
Author(s):  
Catherine Potvin ◽  
Boyd R. Strain
Keyword(s):  
North Carolina ◽  
Co2 Enrichment ◽  
Normal Growth ◽  
Dry Weight ◽  
Single Population ◽  
Eleusine Indica ◽  
Root Dry Weight ◽  
Temperature Regimes ◽  
Net Assimilation ◽  
Growth Analyses

Mathematical growth analyses were carried out on two C4 grasses, Echinochloa crus-galli and Eleusine indica, to test the influence of CO2 enrichment and temperature on growth. Echinochloa populations from Québec, North Carolina, and Mississippi and a single population of Eleusine from Mississippi were grown for 48 days at two CO2 concentrations (350 and 675 μL∙L−1) and three temperature regimes (28:22, 24:18, and 21:15 °C). CO2 enrichment generated an increased root dry weight and induced an earlier development of inflorescences. Net assimilation rate, the only other parameter to respond to CO2 enrichment, was higher for plants grown at high CO2 concentrations during the first harvest interval. Biomass partitioning was affected by temperature. Root dry weight was greater in plants grown at 21:15 °C while more leaf area was produced in warmer temperature regimes. Only plants from Québec maintained normal growth rates under the 21:15 °C regime, suggesting that northern C4 plants are better suited for growth at low temperatures than southern ones.

Sign in / Sign up

Export Citation Format

Share Document