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.

Response of Gas Exchange in Jointed Goatgrass (Aegilops cylindrica) to Environmental Conditions

Weed Science ◽  
1989 ◽  
Vol 37 (4) ◽  
pp. 562-569 ◽  
Author(s):  
David R. Gealy
Keyword(s):  
Soil Moisture ◽  
Gas Exchange ◽  
Environmental Conditions ◽  
Dark Respiration ◽  
Net Photosynthesis ◽  
Soil Matric Potential ◽  
Dark Respiration Rate ◽  
Matric Potential ◽  
Aegilops Cylindrica ◽  
Jointed Goatgrass

Gas exchange of jointed goatgrass leaves was affected by temperature, irradiance level, and soil matric potential. Net photosynthesis of leaves under saturating irradiance (PPFD3= 1850 (μE·m–2·s−1) was optimum at about 20 C. At 25 C, net photosynthesis was nearly 90% of maximum at a PPFD of 800 μE·m–2·−1. Transpiration, and presumably water use, increased steadily with temperature from 10 to 40 C. Dark respiration rate and compensation points for light and for CO2increased exponentially, or nearly so, from 10 to 40 C. Soil moisture deficits of −130 kPa reduced net photosynthesis and transpiration by about 30 and 55%, respectively, compared to well-watered plants.

scholarly journals GAS EXCHANGE CHARACTERISTICS OF FIELD-GROWN `SHAWNEE' BLACKBERRY

HortScience ◽  
1991 ◽  
Vol 26 (6) ◽  
pp. 687G-688
Author(s):  
Curt R. Rom ◽  
John R. Clark
Keyword(s):  
Gas Exchange ◽  
Dark Respiration ◽  
Temperature Response ◽  
Quadratic Function ◽  
Respiration Rates ◽  
Leaf Chamber ◽  
Portable System ◽  
Use Efficiency ◽  
Gas Exchange Characteristics ◽  
Chamber Gas

Gas exchange (assimilation, transpiration, water use efficiency, and conductance) of `Shawnee' blackberry were measured under field conditions with a portable system (ADC-IRGA with Parkinson Leaf Chamber). Gas exchange primocane pentifoliate leaflets were similar. Gas exchange rates of leaves along a cane exhibited a quadratic function of leaf position with leaves in lower-mid sections (relative position 0.3 - 0.5) having higher A, TR, WUE, gs than either basal or apical leaves. Leaves subtending fruiting laterals on fruiticanes had higher assimilation than similar age leaves on primocanes but did not differ in Tr, WUE, or gs. Primocanes had estimated dark respiration rates of 0.33mg·dm-1.hr-1, estimated light compensation at 14-20 mol.m-2.s-1, estimated light saturation at 1000-1100 mol.m-2.s-1 with maximum A rates ranging from 24-30 mg CO2.dm-1.hr-1. Measurements were made at field temperatures ranging from 24-35 C. Although temperature response was not measured, correlation indicated that Tr, WUE, and gs were more closely related to temperature than A. Similarly, Tr and WUE were more closely related to gs than A (r = 0.6 to 0.8).

scholarly journals Altitudinal changes in temperature responses of net photosynthesis and dark respiration in tropical bryophytes

2012 ◽  
Vol 111 (3) ◽  
pp. 455-465 ◽  
Author(s):  
Sebastian Wagner ◽  
Gerhard Zotz ◽  
Noris Salazar Allen ◽  
Maaike Y. Bader
Keyword(s):  
Dark Respiration ◽  
Net Photosynthesis ◽  
Temperature Responses

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.

scholarly journals Canopy Position Affects Light Response Curves for Gas Exchange Characteristics of Apple Spur Leaves

1992 ◽  
Vol 117 (3) ◽  
pp. 467-472 ◽  
Author(s):  
Richard J. Campbell ◽  
Richard P. Marini ◽  
Jeffrey B. Birch
Keyword(s):  
Gas Exchange ◽  
Dark Respiration ◽  
Incident Light ◽  
Light Response ◽  
Net Photosynthesis ◽  
Response Curves ◽  
Light Response Curves ◽  
Light Levels ◽  
Canopy Position ◽  
Gas Exchange Characteristics

Light response curves for gas exchange characteristics were developed for spur leaves of `Stayman' and `Delicious' apple (Malus domestica Borkh.) from interior, intermediate, and exterior canopy positions throughout the season. At full bloom (FB), before full leaf expansion, exterior leaves had higher maximum rates of net photosynthesis (Pn), and a statistically different Pn light response curve than the interior leaves. Intermediate leaves had intermediate Pn rates and light response curves. Pn light response curves for all three `Delicious' canopy positions differed from each other from FB + 6 weeks until the end of the season. Interior leaves had maximum Pn rates of only 50% to 60% of those for the exterior leaves from FB + 10 weeks until the end of the season. Light saturation levels were higher for the exterior leaves than for interior or intermediate leaves. Exterior leaves had a tendency throughout the season for higher quantum efficiency of Pn at subsaturating light levels than interior or intermediate leaves. Stomatal conductance was higher for the exterior than the interior or intermediate leaves of `Delicious' on all dates. Water-use efficiency was equivalent among all leaves. Exterior leaves had higher specific leaf weight, dark respiration rates, and incident light levels on all dates than interior or intermediate leaves.

An Exploration of the Carbon Economy of the Tobacco Plant. III. Gas Exchange of Leaves in Relation to Position on the Stem, Ontogeny and Nitrogen Content

1974 ◽  
Vol 1 (4) ◽  
pp. 551 ◽  
Author(s):  
HM Rawson ◽  
C Hackett
Keyword(s):  
Gas Exchange ◽  
Nitrogen Content ◽  
Time Course ◽  
Dark Respiration ◽  
Tobacco Plant ◽  
Net Photosynthesis ◽  
Developmental Time ◽  
Leaf Ontogeny ◽  
Similar Time ◽  
Carbon Economy

Tobacco plants were grown in sunlit, controlled-environment cabinets, and their growth and gas exchange were followed from shortly after emergence to 90 days from sowing. There were three major findings: 1. Summed over all leaves, dark respiration remained at 6-7% of net photosynthesis for a lengthy period (50-90 days from sowing), but in younger plants the fraction reached as high as 18%. 2. In the 12 leaves monitored from their emergence to full expansion, net photosynthesis (Pn) followed a similar time course, even though the first and last leaves in this group emerged nearly 40 days apart and there was a 100-fold difference in final area (Amax). For a sequence of nine of these leaves, the agreement was so close that their photosynthetic histories could be represented by a single relationship with developmental time. Peak Pn was consistently attained at about 37% Amax, when peak dA/dt occurred, and it was held for only 3-5 days. The subsequent decline reduced Pn to less than one-third of peak Pn at Amax. 3. Data for the nitrogen content (w/w) of the leaves after 37% Amax could be combined in a manner similar to that described for Pn. Pn, nitrogen content and leaf ontogeny were therefore directly related after peak Pn had been attained. The bearing of these findings on the study of photosynthesis in dicotyledonous species is discussed.

Comparative gas exchange physiology in the Daucus carota complex

1978 ◽  
Vol 56 (15) ◽  
pp. 1739-1743 ◽  
Author(s):  
Ernest Small ◽  
R. L. Desjardins
Keyword(s):  
Gas Exchange ◽  
Water Use ◽  
Daucus Carota ◽  
Dark Respiration ◽  
Net Photosynthesis ◽  
Wild Populations ◽  
Stomatal Frequency ◽  
Rate Of Photosynthesis ◽  
Taxonomic Groups

Rates of net photosynthesis, transpiration, and dark respiration of seven populations representing the diversity of the Daucus carota complex were measured. The two taxonomic groups of this complex proved physiologically distinguishable, with subspecies aggregate gingidium possessing lower capacities for photosynthesis and transpiration and a lower frequency of stomata than subspecies aggregate carota. In comparison with wild populations of the complex, cultivars manifested greater efficiency of photosynthesis with respect to water use, possibly the result of an increased demand for photosynthate in domesticated populations. The highest rate of photosynthesis was exhibited by a vigorous, primitive, Asian cultivar, which also possessed the highest stomatal frequency.

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.

Sign in / Sign up

Export Citation Format

Share Document