scholarly journals A Whole-plant, Open, Gas-exchange System for Measuring Net Photosynthesis of Potted Woody Plants

HortScience ◽  
1996 ◽  
Vol 31 (6) ◽  
pp. 944-946 ◽  
Author(s):  
D.P. Miller ◽  
G.S. Howell ◽  
J.A. Flore
Keyword(s):  
Gas Exchange ◽  
Photosynthetically Active Radiation ◽  
Woody Plants ◽  
Net Photosynthesis ◽  
Growing Season ◽  
Exchange System ◽  
Active Radiation ◽  
Whole Plant ◽  
Short Period ◽  
Gas Exchange System

Chambers were constructed to measure gas exchange of entire potted grapevines (Vitis vinifera L.). The plant enclosures were constructed from Mylar film, which is nearly transparent to photosynthetically active radiation. Maintaining a slight, positive, internal pressure allowed the Mylar chambers to inflate like balloons and required no other means of support. The whole-plant, gas-exchange chamber design and construction were simple and inexpensive. They were assembled easily, equilibrated quickly, and did not require cooling. They allowed for the measurement of many plants in a relatively short period. This system would enable the researcher to make replicated comparisons of treatment influences on whole-plant CO2 assimilation throughout the growing season. While CO2 measurement was the focus of this project, it would be possible to measure whole-plant transpiration with this system.

Photosynthesis and transpiration in large forest-grown Douglas-fir: interactions with apical control

1981 ◽  
Vol 59 (12) ◽  
pp. 2568-2576 ◽  
Author(s):  
Jerry W. Leverenz
Keyword(s):  
Gas Exchange ◽  
Exchange Rates ◽  
Pseudotsuga Menziesii ◽  
Net Photosynthesis ◽  
Douglas Fir ◽  
Exchange System ◽  
Apical Control ◽  
Lateral Shoots ◽  
Terminal Shoot ◽  
Gas Exchange System

Net photosynthesis, transpiration, and stomatal and residual conductances for current-year shoots of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) were measured in an open gas exchange system. Terminal shoots of branches and branchlets had larger stomatal and residual conductances, and net photosynthetic and transpiration rates than neighboring lateral shoots under conditions which did not limit gas exchange. The differences between terminal and lateral shoots occurred in both exposed and shaded branches and in trees of different dominance classes. For most of the study, current-year lateral shoots were lighter green than terminal shoots. There were no significant differences in shoot water potential or in the microenvironment between terminal and lateral shoots.Effects of apical control on gas exchange rates were strong in shoots subtending the dominant terminal shoot. These effects were not apparent four whorls from the terminal shoot, in agreement with the hypothesis that apical control can not be exerted at long distances from terminal shoots.

Red spruce seedling gas exchange in response to elevated CO2, water stress, and soil fertility treatments

1994 ◽  
Vol 24 (5) ◽  
pp. 954-959 ◽  
Author(s):  
L.J. Samuelson ◽  
J.R. Seiler
Keyword(s):  
Water Stress ◽  
Gas Exchange ◽  
Soil Fertility ◽  
Net Photosynthesis ◽  
Growing Season ◽  
Red Spruce ◽  
Fertility Treatment ◽  
Sink Strength ◽  
Growth Enhancement ◽  
Growing Seasons

The interactive influences of ambient (374 μL•L−1) or elevated (713 μL•L−1) CO2, low or high soil fertility, well-watered or water-stressed treatment, and rooting volume on gas exchange and growth were examined in red spruce (Picearubens Sarg.) grown from seed through two growing seasons. Leaf gas exchange throughout two growing seasons and growth after two growing seasons in response to elevated CO2 were independent of soil fertility and water-stress treatments, and rooting volume. During the first growing season, no reduction in leaf photosynthesis of seedlings grown in elevated CO2 compared with seedlings grown in ambient CO2 was observed when measured at the same CO2 concentration. During the second growing season, net photosynthesis was up to 21% lower for elevated CO2-grown seedlings than for ambient CO2-grown seedlings when measured at 358 μL•L−1. Thus, photosynthetic acclimation to growth in elevated CO2 occurred gradually and was not a function of root-sink strength or soil-fertility treatment. However, net photosynthesis of seedlings grown and measured at an elevated CO2 concentration was still over 2 times greater than the photosynthesis of seedlings grown and measured at an ambient CO2 concentration. Growth enhancement by CO2 was maintained, since seedlings grown in elevated CO2 were 40% larger in both size and weight after two growing seasons.

scholarly journals Chronicvs.Short-Term Acute O3Exposure Effects on Nocturnal Transpiration in Two Californian Oaks

2007 ◽  
Vol 7 ◽  
pp. 134-140 ◽  
Author(s):  
N. E. Grulke ◽  
E. Paoletti ◽  
R. L. Heath
Keyword(s):  
Gas Exchange ◽  
Water Loss ◽  
Exchange System ◽  
Short Term ◽  
Blue Oak ◽  
Unexposed Control ◽  
Nocturnal Transpiration ◽  
Gas Exchange System ◽  
Black Oak ◽  
Oak Seedlings

We tested the effect of daytime chronic moderate ozone (O3) exposure, short-term acute exposure, and both chronic and acute O3exposure combined on nocturnal transpiration in California black oak and blue oak seedlings. Chronic O3exposure (70 ppb for 8 h/day) was implemented in open-top chambers for either 1 month (California black oak) or 2 months (blue oak). Acute O3exposure (~1 h in duration during the day, 120–220 ppb) was implemented in a novel gas exchange system that supplied and maintained known O3concentrations to a leaf cuvette. When exposed to chronic daytime O3exposure, both oaks exhibited increased nocturnal transpiration (without concurrent O3exposure) relative to unexposed control leaves (1.8× and 1.6×, black and blue oak, respectively). Short-term acute and chronic O3exposure did not further increase nocturnal transpiration in either species. In blue oak previously unexposed to O3, short-term acute O3exposure significantly enhanced nocturnal transpiration (2.0×) relative to leaves unexposed to O3. California black oak was unresponsive to (only) short-term acute O3exposure. Daytime chronic and/or acute O3exposures can increase foliar water loss at night in deciduous oak seedlings.

scholarly journals Overexpression of Plasma Membrane H+-ATPase in Guard Cells Enhances Light-Induced Stomatal Opening, Photosynthesis, and Plant Growth in Hybrid Aspen

2021 ◽  
Vol 12 ◽  
Author(s):  
Shigeo Toh ◽  
Naoki Takata ◽  
Eigo Ando ◽  
Yosuke Toda ◽  
Yin Wang ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Transgenic Plants ◽  
Woody Plants ◽  
Stem Elongation ◽  
Guard Cells ◽  
Gus Expression ◽  
Stomatal Opening ◽  
Wild Type ◽  
Exchange System ◽  
Gas Exchange System

Stomata in the plant epidermis open in response to light and regulate CO2 uptake for photosynthesis and transpiration for uptake of water and nutrients from roots. Light-induced stomatal opening is mediated by activation of the plasma membrane (PM) H+-ATPase in guard cells. Overexpression of PM H+-ATPase in guard cells promotes light-induced stomatal opening, enhancing photosynthesis and growth in Arabidopsis thaliana. In this study, transgenic hybrid aspens overexpressing Arabidopsis PM H+-ATPase (AHA2) in guard cells under the strong guard cell promoter Arabidopsis GC1 (AtGC1) showed enhanced light-induced stomatal opening, photosynthesis, and growth. First, we confirmed that AtGC1 induces GUS expression specifically in guard cells in hybrid aspens. Thus, we produced AtGC1::AHA2 transgenic hybrid aspens and confirmed expression of AHA2 in AtGC1::AHA2 transgenic plants. In addition, AtGC1::AHA2 transgenic plants showed a higher PM H+-ATPase protein level in guard cells. Analysis using a gas exchange system revealed that transpiration and the photosynthetic rate were significantly increased in AtGC1::AHA2 transgenic aspen plants. AtGC1::AHA2 transgenic plants showed a>20% higher stem elongation rate than the wild type (WT). Therefore, overexpression of PM H+-ATPase in guard cells promotes the growth of perennial woody plants.

Regulation of Carboxylation and Photosynthetic Oscillations During Sun-Shade Acclimation in Helianthus annuus Measured With a Rapid-Response Gas Exchange System

1988 ◽  
Vol 15 (2) ◽  
pp. 239 ◽  
Author(s):  
CB Osmond ◽  
V Oja ◽  
A Laisk
Keyword(s):  
Gas Exchange ◽  
Intercellular Co2 Concentration ◽  
Photosynthetic Apparatus ◽  
Co2 Concentration ◽  
Rapid Response ◽  
Exchange System ◽  
Dynamic Regulation ◽  
Bisphosphate Carboxylase ◽  
Shade Acclimation ◽  
Gas Exchange System

The consequences of acclimation from shade to sun and vice versa for regulated photosynthetic metabolism were examined in H. annuus. A rapid-response gas exchange system was used to assess changes in carboxylation-related parameters (mesophyll conductance, assimilatory charge and CO2 capacity) and to analyse oscillations in CO2 fixation following transfer to high CO2 concentration as a function of intercellular CO2 concentration and light intensity. Data showed a two- to threefold change in all carboxylation-related parameters during acclimation in either direction. Dynamic regulation of carboxylation, indicated by changes in oscillatory response as a function of CO2 concentration at light saturation, remained unchanged, consistent with concerted regulation of ribulose-1,5-bisphosphate carboxylase-oxygenase during acclimation. However, the light dependency of oscillations changed during acclimation from shade to sun, and the range of oscillation was closely tied to the maximum rate of steady-state photosynthesis at CO2 saturation. These data imply that changes in the light-absorbing and electron transport components of the photosynthetic apparatus underlie the shift in regulatory behaviour during acclimation.

Gas-blood PCO2 gradients during avian gas exchange

1975 ◽  
Vol 39 (3) ◽  
pp. 405-410 ◽  
Author(s):  
D. G. Davies ◽  
R. E. Dutton
Keyword(s):  
Gas Exchange ◽  
Exchange System ◽  
Arterial Pco2 ◽  
Charged Membrane ◽  
Venous Pco2 ◽  
Avian Lung ◽  
Gas Exchange System ◽  
Spontaneously Breathing ◽  
Membrane Mechanism ◽  
Mixed Venous

The avian respiratory system is a crosscurrent gas exchange system. One of the aspects of this type of gas exchange system is that end-expired PCO2 is greater than arterial PCO2, the highest possible value being equal to mixed venous PCO2. We made steady-state measurements of arterial, mixed venous, and end-expired PCO2 in anesthetized, spontaneously breathing chickens during inhalation of room air or 4–8% CO2. We found end-expired PCO2 to be higher than both arterial and mixed venous PCO2, the sign of the differences being such as to oppose passive diffusion. The observation that end-expired PCO2 was higher than arterial PCO2 can be explained on the basis of crosscurrent gas exchange. However, the observation that end-expired PCO2 exceeded mixed venous PCO2 must be accounted for by some other mechanism. The positive end-expired to mixed venous PCO2 gradients can be explained if it is postulated that the charged membrane mechanism suggested by Gurtner et al. (Respiration Physiol. 7: 173–187, 1969) is present in the avian lung.

scholarly journals Food production and gas exchange system using blue-green alga (Spirulina) for CELSS

1987 ◽  
Vol 7 (4) ◽  
pp. 7-10 ◽  
Author(s):  
Mitsuo Oguchi ◽  
Koji Otsubo ◽  
Keiji Nitta ◽  
Shigeki Hatayama
Keyword(s):  
Gas Exchange ◽  
Green Alga ◽  
Food Production ◽  
Blue Green Alga ◽  
Exchange System ◽  
Gas Exchange System

Formation of the photosynthetic indicators of spring wheat depending on the variety and pre-sowing treatment

10.12737/1361 ◽  
2013 ◽  
Vol 8 (3) ◽  
pp. 96-100
Author(s):  
Воробьева ◽  
Tatyana Vorobeva ◽  
Шашкаров ◽  
Leonid Shashkarov
Keyword(s):  
Leaf Area ◽  
Spring Wheat ◽  
Photosynthetically Active Radiation ◽  
Seed Treatment ◽  
Net Photosynthesis ◽  
Coefficient Of Performance ◽  
Cropping Pattern ◽  
Efficiency Coefficient ◽  
Active Radiation ◽  
Photosynthetic Productivity

This article describes the formation of leaf area, photosynthetic capacity of crops, the net photosynthetic efficiency, leaves productivity and efficiency, Coefficient of performance (COP) of photosynthetically active radiation (PAR) of spring wheat, using Nano- Gro seed treatment instead of the traditional etching, depending on the varietal characteristics o dark gray forest soils of the Nizhniy Novgorod region. The study was carried out on varieties Margarita, Marusya and Sofia. In connection with this problem, above-mentioned issues are relevant to the present day. Rising the yields of spring wheat to the level of its genetically determined potential is only possible with an increase in photosynthetic productivity of crops, primarily due to the proper selection of varieties for specific soil-climatic zones. Cropping pattern should provide the absorption of at least 2% of PAR. The main absorbing body is a leaf. Therefore the need for a crop with optimum leaf surface area. The study revealed the following, the maximum leaf area of plants of spring wheat is formed in earing seed treatment by Nano-Gro. On average, during the growing season net photosynthesis productivity of Margarita variety was 4.5-5.7 g/m2, Maroussia - 4.6-4.8 g/m2 and Sofia - 3.8-5.2 g/m2. Maximum values of net photosynthetic productivity of crops are characterized by variations in seed treatment by Nano-Gro and Margarita variety. The highest efficiency (2.46, 2.57 and 2.55 kg by 1000 units) was observed on the leaves treated by Nano-Gro and the efficiency of Coefficient of performance (COP) of photosynthetically active radiation (PAR) is 1,54-1,81 %. Margarita and Marussia were characterized by maximum values of productivity of leaf and Coefficient of performance (COP) of photosynthetically active radiation (PAR).

Sign in / Sign up

Export Citation Format

Share Document