A Controlled-environment Leaf Chamber to Allow Measurement of Gas Exchange by Leaves Undergoing Rapid Fluctuations in Temperature

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).

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Photosynthesis and CO2 evolution by leaf discs: gas exchange, extraction, and ion-exchange fractionation of 14C-labeled photosynthetic products

Canadian Journal of Botany ◽

10.1139/b71-171 ◽

1971 ◽

Vol 49 (7) ◽

pp. 1225-1234 ◽

Cited By ~ 84

Author(s):

C. A. Atkins ◽

D. T. Canvin

Keyword(s):

Gas Exchange ◽

Ion Exchange ◽

Gas Analysis ◽

Co2 Evolution ◽

Leaf Discs ◽

Leaf Chamber ◽

Rate Of Photosynthesis ◽

Photosynthetic Products ◽

Exchange Extraction ◽

Analysis System

A leaf chamber is described which allows the measurement of the gas exchange of leaf discs in an open gas analysis system. Pretreatment of the leaf discs with nitrogen and inclusion of moist filter paper in the leaf chamber resulted in rates of photosynthesis that were constant for 40 min and equal to 60 to 70% of the rate of photosynthesis measured in intact leaves. Analysis of the products of 14CO2 fixation from whole leaves and leaf discs and a comparison of the gas exchange under various conditions established that the leaf discs accurately reflected the metabolism of the attached leaves.

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Stomatal Behaviour of Kenaf and Sorghum in a Semiarid Tropical Environment. I. During the Night

Functional Plant Biology ◽

10.1071/pp9800609 ◽

1980 ◽

Vol 7 (5) ◽

pp. 609 ◽

Cited By ~ 14

Author(s):

RC Muchow ◽

MM Ludlow ◽

MJ Fisher ◽

RJK Myers

Keyword(s):

Soil Water ◽

Water Status ◽

Hibiscus Cannabinus ◽

Stomatal Opening ◽

Controlled Environment ◽

Night Time ◽

Soil Water Status ◽

Stomatal Behaviour ◽

Leaf Chamber ◽

Sorghum Bicolor L

The extent of night-time stomatal opening in field-grown kenaf (Hibiscus cannabinus L.), a C3 dicotyledon, and sorghum [Sorghum bicolor (L.) Moench], a C4 grass, and the factors controlling the opening were studied at high and low soil water status. Since saturation deficit (δe) and temperature varied together in the field, the response of stomatal conductance (gs) to these individual factors was determined under controlled environment conditions in a leaf chamber apparatus. At both high and low soil water status, the stomata of sorghum were closed from sunset to sunrise, whereas with kenaf partial stomatal opening was observed throughout the night. Initiation of night opening occurred in response to decreasing temperature, but the degree of opening was determined by plant water status. The importance of night-time stomatal opening on the water relations of the crop is discussed.

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Effects of elevated CO2 , drought and temperature on the water relations and gas exchange of groundnut (Arachis hypogaea) stands grown in controlled environment glasshouses

Physiologia Plantarum ◽

10.1034/j.1399-3054.2000.110111.x ◽

2000 ◽

Vol 110 (1) ◽

pp. 78-88 ◽

Cited By ~ 28

Author(s):

Sean C. Clifford ◽

Ian M. Stronach ◽

Colin R. Black ◽

Paul R. Singleton-Jones ◽

Sayed N. Azam-Ali ◽

...

Keyword(s):

Gas Exchange ◽

Elevated Co2 ◽

Arachis Hypogaea ◽

Water Relations ◽

Controlled Environment

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Light spectrum affects growth and gas exchange of common dandelion and purple coneflower seedlings

International Journal of Plant Biology ◽

10.4081/pb.2016.6281 ◽

2016 ◽

Vol 7 (1) ◽

Author(s):

Donato Castronuovo ◽

Adriano Sofo ◽

Stella Lovelli ◽

Vincenzo Candido ◽

Antonio Scopa

Keyword(s):

Gas Exchange ◽

Chlorophyll Content ◽

Experimental Period ◽

Photosynthetic Performance ◽

Controlled Environment ◽

Artificial Light ◽

Light Sources ◽

Light Spectrum ◽

Purple Coneflower ◽

Common Dandelion

Artificial light, supplied by fluorescent lamps, has been effectively utilized in controlled- environment chambers for horticulture and floriculture nursery. This experiment aimed at investigating whether light-emitting diodes (LEDs) have the same effectiveness on plant morphology, photosynthetic and physiological responses as FLUORA lamps. Seedlings of common dandelion (Taraxacum officinale) and purple coneflower (Echinacea purpurea), species of high interest for their nutraceutical properties, were grown in controlled-environment chambers for 50 days under LED and FLUORA light sources as sole-source lighting systems, and the effects of artificial light supplies on plant photosynthetic performance and chlorophyll content (SPAD) were evaluated. The results were compared to plants grown under natural sunlight. In both species, total chlorophyll content (SPAD) values decreased for plants under sunlight, and for those grown under FLUORA lighting throughout the experimental period, while the values measured for plants grown under LEDs maintained a relatively constant value. At the end of the experiment, plant dry matter in both species was significantly lower under LEDs and FLUORA lighting, than the plants exposed to solar light. The two species showed different gas exchange dynamics under LEDs and FLUORA lighting, and photosynthetic performance decreasing after 10 days of light treatment compared to plants under sunlight. The results demonstrated that for common dandelion and purple coneflower photosynthetic processes are often modified when the species are cultivated under these artificial lighting and in controlled- environment chambers, because lamps do not able to generate the same spectrum and energy of sunlight.

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Factors influencing the measurement of assimilation and stomatal conductance with the LI-COR 6400XT gas exchange system.

10.1101/494120 ◽

2018 ◽

Author(s):

Daniel LeCain ◽

Sean Gleason

Keyword(s):

Stomatal Conductance ◽

Gas Exchange ◽

Experimental Error ◽

Leaf Age ◽

Time Of Day ◽

Species Variation ◽

Plant Responses ◽

Exchange System ◽

Leaf Chamber ◽

Gas Exchange System

Abstract: Although CO2 and H2O exchange rates are often measured in experiments as indicators of physiological plant responses these gas exchange measurements are prone to large experimental error. Gas exchange equipment and technology have improved greatly over the past two decades which supports scrutinizing current issues of experimental error in measuring plant photosynthesis and stomatal conductance. This report shows results of a greenhouse experiment with the goal of identifying lessor understood sources of experimental error and variation in measurements with the LI-COR 6400XT gas exchange system. A variety of plant types were used to encompass differing species variation. We found significant sources of experimental error in 1) the time for initial adjustment when placing a leaf in the leaf chamber 2) the time-of-day when measuring 3) leaf age 4) having the chamber window full vs. partially full with leaf tissue 5) using a leaf chamber environment that greatly diverges from the whole plant environment 6) differing degree of experimental error depending upon plant species. A situation with multiple contributors to error would result in useless gas-exchange data. Recommendations for minimizing these experimental errors are given.

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Repeated Mechanical Stress from Leaf Cuvette Influences Leaf Gas Exchange

HortScience ◽

10.21273/hortsci.27.5.432 ◽

1992 ◽

Vol 27 (5) ◽

pp. 432-434 ◽

Cited By ~ 3

Author(s):

Thomas E. Marler ◽

Michael V. Mickelbart

Keyword(s):

Stomatal Conductance ◽

Gas Exchange ◽

Mechanical Stress ◽

Leaf Gas Exchange ◽

Mangifera Indica ◽

Mechanical Stimulus ◽

Persea Americana ◽

Long Term Effects ◽

Leaf Chamber ◽

Fixed Set

Long-term effects on stomatal conductance of mechanical stress from repeated clamping of a porometer leaf cuvette to laminae of avocado (Persea americana Miller), carambola (Averrhoa carambolu L.), hibiscus (Hibiscus rosa-sinensis L.), mango (Mangifera indica L.), and sugar apple (Annona squamosa L.) plants were determined under glasshouse conditions. Following 10 weeks of applying the mechanical stimulus seven times during every 4th day to mature leaves, stomatal conductance was lower than for untreated leaves of all species except mango. Similarly, following 10.5 weeks of applying the stimulus one time every 4th day to expanding leaves of avocado, carambola, hibiscus, and sugar apple, stomatal conductance was lower than for untreated leaves of the same age in all species except hibiscus. Carambola and sugar apple were more sensitive to the mechanical stress than the other species. Thus, the indirect effect of leaf chamber clamping on gas exchange should be known before any conclusions are formulated regarding environmental, cultural, or genetic effects on gas exchange. Random leaf samples from a canopy instead of measurements on a fixed set of leaves may be more appropriate for repeated determinations of leaf gas exchange on a set of plants.

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