CO2 and water vapor exchange of Pinustaeda in relation to stomatal behavior: test of an optimization hypothesis

1988 ◽  
Vol 18 (2) ◽  
pp. 150-157 ◽  
Author(s):  
J. A. Fites ◽  
R. O. Teskey
Keyword(s):  
Water Vapor ◽  
Stomatal Conductance ◽  
Absolute Humidity ◽  
Net Photosynthesis ◽  
High Irradiance ◽  
Carbon Gain ◽  
Gain Ratio ◽  
Stomatal Behavior ◽  
Diurnal Patterns ◽  
Behavior Test

Responses of CO2 and water vapor exchange to absolute humidity deficit (AHD) were measured for seedlings of Pinustaeda L. at high and low irradiance in the laboratory. Diurnal patterns of CO2 and water vapor exchange of P. taeda seedlings and trees were monitored in the field. Stomatal behavior was evaluated in relation to a recent hypothesis of "optimal" stomatal behavior, in which changes in stomatal conductance in response to environmental variation are such that water loss is minimized for a given amount of carbon gain. That is, when stomatal behavior is "optimal," the ratio (gain ratio) of the sensitivities of transpiration and net photosynthesis to changes in stomatal conductance [Formula: see text] is constant.Laboratory and field stomatal behavior generally did not conform with this hypothesis. Under controlled conditions, at high irradiance, the gain ratio increased with AHD. In the field, the gain ratio increased diurnally on most days. Increasing gain ratios were associated with increasing [Formula: see text] values but relatively uniform [Formula: see text] values. Uniform gain ratios in the field were observed on some days, associated with uniform environment, constant [Formula: see text], or varying [Formula: see text] values.

Change in photosynthesis and water relations with age and season in Abiesamabilis

1984 ◽  
Vol 14 (1) ◽  
pp. 77-84 ◽  
Author(s):  
R. O. Teskey ◽  
C. C. Grier ◽  
T. M. Hinckley
Keyword(s):  
Water Stress ◽  
Stomatal Conductance ◽  
Water Relations ◽  
Net Photosynthesis ◽  
Carbon Gain ◽  
Xylem Water Potential ◽  
Needle Age ◽  
Stressful Environment ◽  
Competitive Success ◽  
One Year

Seasonal changes in water relations and net photosynthesis were measured over a year in current and 1-year-old foliage of Abiesamabilis (Dougl.) Forbes, a subalpine conifer. Responses were compared with maximum rates achieved in older foliage. Current-year foliage developed slowly during the growing season. Although growth began on 22 June, highest rates of stomatal conductance and net photosynthesis did not occur until September and October. One-year-old foliage had the highest rates of net photosynthesis (12.9 mg CO2•dm−2•h−1) and stomatal conductance (3.1 mm•s−1) during the summer. Net photosynthesis decreased with needle age, but foliage as old as 7 years had rates of net photosynthesis as high as 5.0 mg CO2•dm−2•h−1. There was no evidence of photosynthetic adjustment to seasonal change in temperature. The optimum temperature for photosynthesis remained at 15 ± 1.5 °C throughout the year. No water stress was observed during the summer. Xylem water potential never decreased below −1.65 MPa and was always well above the turgor loss point. The lack of any apparent water stress, combined with photosynthetic characteristics, indicated that summer was the most important season for carbon gain. These results also suggested that a strategy for competitive success by Abiesamabilis in this cold, stressful environment is minimum dependence on the carbon gain of any individual age-class of foliage. Instead trees rely on the combined photosynthetic capacity of many years of foliage.

scholarly journals Parameterization of a coupled CO<sub>2</sub> and H<sub>2</sub>O gas exchange model at the leaf scale of <i>Populus euphratica</i>

2010 ◽  
Vol 14 (3) ◽  
pp. 419-431 ◽  
Author(s):  
G. F. Zhu ◽  
X. Li ◽  
Y. H. Su ◽  
C. L. Huang
Keyword(s):  
Stomatal Conductance ◽  
Gas Exchange ◽  
Electron Transport Rate ◽  
Populus Euphratica ◽  
Coupled Model ◽  
Net Photosynthesis ◽  
Combined Model ◽  
Validation Data ◽  
Bisphosphate Carboxylase ◽  
Diurnal Patterns

Abstract. The following two models were combined to simultaneously predict CO2 and H2O gas exchange at the leaf scale of Populus euphratica: a Farquhar et al. type biochemical sub-model of photosynthesis (Farquhar et al., 1980) and a Ball et al. type stomatal conductance sub-model (Ball et al., 1987). The photosynthesis parameters [including maximum carboxylation rate allowed by ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) carboxylation rate (Vcmax), potential light-saturated electron transport rate (Jmax), triose phosphate utilization (TPU) and day respiration (Rd)] were determined by using the genetic algorithm (GA) method based on A/Ci data. Values of Vcmax and Jmax standardized at 25 °C were 75.09±1.36 (mean ± standard error), 117.27±2.47, respectively. The stomatal conductance sub-model was calibrated independently. Prediction of net photosynthesis by the coupled model agreed well with the validation data, but the model tended to underestimate transpiration rates. Overall, the combined model generally captured the diurnal patterns of CO2 and H2O exchange resulting from variation in temperature and irradiation.

scholarly journals Parameterization of the coupling CO<sub>2</sub> and H<sub>2</sub>O gas exchange model at the leaf scale of <i>Populus euphratica</i> tree

2009 ◽  
Vol 6 (5) ◽  
pp. 6503-6534
Author(s):  
G. Zhu ◽  
X. Li ◽  
Y. Su ◽  
C. Huang
Keyword(s):  
Stomatal Conductance ◽  
Gas Exchange ◽  
Populus Euphratica ◽  
Coupled Model ◽  
Net Photosynthesis ◽  
Data Sets ◽  
Validation Data ◽  
Bisphosphate Carboxylase ◽  
Diurnal Patterns ◽  
Ribulose 1

Abstract. The following two models were combined to predict simultaneously CO2 and H2O gas exchange at the leaf scale of Populus euphratica: a Farquhar et al. type biochemical sub-model of photosynthesis (Farquhar et al., 1980) and a Ball et al. type stomatal conductance sub-model (Ball et al., 1987). The photosynthesis parameters, Vcmax, Jmax, TPU, and Rd (maximum carboxylation rate allowed by ribulose 1·5-bisphosphate carboxylase/oxygenase (Rubisco), rate of phosynthetic electron transport, triose phosphate use, and day respiration) at the measurement temperature were determined by using the genetic algorithm (GA) method based on A/Ci data sets. The stomatal conductance sub-model was calibrated independently. Prediction of net photosynthesis by the coupled model agreed well with the validation data, but the model tended to underestimate rates of transpiration. Overall, the combined model generally captured the diurnal patterns of CO2and H2O exchange resulting from variation in temperature and irradiation.

Seasonal and diurnal patterns in leaf gas exchange of Eucalyptusglobulus trees growing in Portugal

1986 ◽  
Vol 16 (2) ◽  
pp. 177-184 ◽  
Author(s):  
J. S. Pereira ◽  
J. D. Tenhunen ◽  
O. L. Lange ◽  
W. Beyschlag ◽  
A. Meyer ◽  
...  
Keyword(s):  
Stomatal Conductance ◽  
Gas Exchange ◽  
Leaf Gas Exchange ◽  
Carbon Assimilation ◽  
Net Photosynthesis ◽  
Severe Drought ◽  
Midday Depression ◽  
Diurnal Patterns ◽  
Use Efficiency ◽  
Photosynthetic Carbon Assimilation

Gas exchange of adult leaves of Eucalyptusglobulus Labill. trees growing in Portugal was monitored during weekly periods between September 1982 and August 1983. Photosynthetic carbon assimilation rates and leaf water use efficiency were highest (maximum instantaneous values, ca. 12 μmol CO2 m−2 s−1 and ca. 7 mmol CO2 mol H2O−1, respectively) in the spring, somewhat reduced in the winter, and strongly depressed by the middle of the summer, when severe drought conditions prevailed. Diurnal patterns of variation in stomatal conductance and net photosynthesis rates showed a marked seasonal variation. With the transition from winter to spring and summer, as the environmental conditions became warmer and drier, there was an increasing tendency for a midday depression in gas exchange rates as well as a decreasing capacity in the afternoon for recovery to the same net photosynthesis rates measured in the morning. Midday depression in gas exchange and stomatal conductance occurred in leaves positioned both vertically and horizontally inside the measurement cuvettes. Leaf dark respiratory rates also changed with the season; the temperature necessary to evoke similar rates increased with the transition from winter to summer.

scholarly journals Physiological responses of beet plants irrigated with saline water and silicon application

2020 ◽  
Vol 11 ◽  
pp. E3113
Author(s):  
José Sebastião de Melo Filho ◽  
Toshik Iarley da Silva ◽  
Anderson Carlos de Melo Gonçalves ◽  
Leonardo Vieira de Sousa ◽  
Mario Leno Martins Véras ◽  
...  
Keyword(s):  
Stomatal Conductance ◽  
Gas Exchange ◽  
Carbon Concentration ◽  
Saline Water ◽  
Block Design ◽  
Essential Element ◽  
Net Photosynthesis ◽  
Crop Productivity ◽  
Experimental Unit ◽  
Randomized Block Design

Although not considered an essential element, silicon can be used to increase crop productivity, especially under stress conditions. In this sense, the objective was to evaluate the gas exchange of beet plants irrigated with saline water depending on the application of silicon. The experiment was conducted in a randomized block design, in a 5 x 5 factorial, referring to five levels of electrical conductivity of irrigation water (ECw): (0.5; 1.3; 3.25; 5.2 and 6.0 dS m-1) and five doses of silicon (0.00; 2.64; 9.08; 15.52 and 18.16 mL L-1), with six beet plants as an experimental unit. The effect of treatments on beet culture was evaluated at 30 and 60 days after irrigation with saline water from measurements of internal carbon concentration, stomatal conductance, net photosynthesis rate, instantaneous water use efficiency and instantaneous carboxylation efficiency using the LCpro+Sistem infrared gas analyzer (IRGA). Irrigation with saline water reduced the gas exchange of beet plants at 60 days after irrigation, but at 30 days after irrigation, the use of saline water increased stomatal conductance, transpiration rate and internal carbon concentration. The application of silicon decreased stomatal conductance, internal carbon concentration and efficiency in the use of water, but increased the rate of net photosynthesis, the rate of transpiration and instantaneous efficiency of carboxylation at 30 and 60 days after irrigation.

Effects of frozen storage duration and soil temperature on the stomatal conductance and net photosynthesis of Piceaglauca seedlings

1993 ◽  
Vol 23 (12) ◽  
pp. 2459-2466 ◽  
Author(s):  
George J. Harper ◽  
Edith L. Camm
Keyword(s):  
Stomatal Conductance ◽  
Soil Temperature ◽  
Carbon Fixation ◽  
Frozen Storage ◽  
Net Photosynthesis ◽  
Storage Duration ◽  
Growing Period ◽  
Soil Temperatures ◽  
Low Levels ◽  
And Storage

Nursery grown seedlings of Piceaglauca (Moench) Voss were stored frozen in the dark from approximately 10–31 weeks, thawed and grown for 28 days in a growth chamber at three soil temperatures (3, 7, and 11 °C). During the growing period gas exchange measurements were made every three days. Seedling net photosynthesis (pn) and stomatal conductance (gs) showed significant interactions between soil temperature and storage duration treatments. Soil temperature did not affect seedling gs or pn, though the degree and extent of storage duration effects were dependent on soil temperature. Recovery of gs occurred over a 4–7 day period from low levels after planting. Seedlings stored longer than 22 weeks showed lower rates of pn, than those stored for shorter durations. The lower pn in long-stored seedlings did not result from stomatal limitations to carbon fixation, as gs increased in seedlings stored >22 weeks.

Photosynthesis and physiological traits of evergreen broadleafed saplings during winter under different light environments in a temperate forest

2006 ◽  
Vol 84 (1) ◽  
pp. 60-69 ◽  
Author(s):  
Yoshiyuki Miyazawa ◽  
Kihachiro Kikuzawa
Keyword(s):  
Temperate Forest ◽  
Light Availability ◽  
Net Photosynthesis ◽  
Carbon Gain ◽  
Leaf Mass Per Area ◽  
Camellia Japonica ◽  
Leaf Mass ◽  
Unit Leaf ◽  
Canopy Trees ◽  
Photosynthetic Traits

Photosynthetic traits of the evergreen broadleafed species Camellia japonica L. and Quercus glauca Thunb. were continuously investigated during autumn and winter using saplings that grew in different light environments (gap, deciduous canopy understory, and evergreen canopy understory) in a temperate forest. Light-saturated rates of net photosynthesis in midwinter and spring were lower than those in autumn. Photosynthetic capacity, scaled to a common leaf temperature of 25 °C, increased or remained stable after autumn and then decreased in spring in most leaves. Photosynthetic traits per unit leaf area were different among leaves in different light environments of both Camellia and Quercus during most periods. However, photosynthetic traits per unit leaf mass did not differ among leaves in different light environments, suggesting that differences in photosynthetic traits were mainly due to different leaf mass per area among leaves. Photosynthetic rates under light availability typical in the environment were lower in winter than in autumn in leaves in the sun in a gap but were not different in leaves in the shade under evergreen canopy trees. Thus, the importance of winter carbon gain for annual carbon gain is small in leaves in a gap but is large in leaves under evergreen canopy trees.

scholarly journals High-yielding rice Takanari has superior photosynthetic response to a commercial rice Koshihikari under fluctuating light

2019 ◽  
Vol 70 (19) ◽  
pp. 5287-5297 ◽  
Author(s):  
Shunsuke Adachi ◽  
Yu Tanaka ◽  
Atsuko Miyagi ◽  
Makoto Kashima ◽  
Ayumi Tezuka ◽  
...  
Keyword(s):  
Electron Transport ◽  
Stomatal Conductance ◽  
Metabolic Flux ◽  
Electron Transport Rate ◽  
Rice Cultivar ◽  
Carbon Gain ◽  
High Electron ◽  
Photosynthetic Induction ◽  
Photosynthetic Response ◽  
Fluctuating Light

The high-yielding rice cultivar Takanari has fast photosynthetic induction owing to a high electron transport rate, stomatal conductance, and metabolic flux, leading to high daily carbon gain under fluctuating light.

Genetic gains in grain yield, net photosynthesis and stomatal conductance achieved in Henan Province of China between 1981 and 2008

2011 ◽  
Vol 122 (3) ◽  
pp. 225-233 ◽  
Author(s):  
T.C. Zheng ◽  
X.K. Zhang ◽  
G.H. Yin ◽  
L.N. Wang ◽  
Y.L. Han ◽  
...  
Keyword(s):  
Stomatal Conductance ◽  
Grain Yield ◽  
Net Photosynthesis ◽  
Henan Province ◽  
Genetic Gains
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