Gas-exchange response and stomatal and non-stomatal limitations to carbon assimilation of sunflower under salinity

Stomata are cellular pores on the leaf epidermis that allow plants to regulate carbon assimilation and water loss. Stomata integrate environmental signals to regulate pore apertures and optimize gas exchange to fluctuating conditions. Here, we quantified intraspecific plasticity of stomatal gas exchange and anatomy in response to seasonal variation in Brachypodium distachyon. Over the course of two years we (i) used infrared gas analysis to assess light response kinetics of 120 Bd21-3 wild-type individuals in an environmentally fluctuating greenhouse and (ii) microscopically determined the seasonal variability of stomatal anatomy in a subset of these plants. We observed systemic environmental effects on gas exchange measurements and remarkable intraspecific plasticity of stomatal anatomical traits. To reliably link anatomical variation to gas exchange, we adjusted anatomical gsmax calculations for grass stomatal morphology. We propose that systemic effects and variability in stomatal anatomy should be accounted for in long-term gas exchange studies.

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Visible Foliar Injury and Physiological Responses to Ozone in Italian Provenances ofFraxinus excelsiorandF. ornus

The Scientific World JOURNAL ◽

10.1100/tsw.2007.10 ◽

2007 ◽

Vol 7 ◽

pp. 90-97 ◽

Cited By ~ 17

Author(s):

Nicla Contran ◽

Elena Paoletti

Keyword(s):

Gas Exchange ◽

Physiological Responses ◽

Carbon Assimilation ◽

Woody Species ◽

Green Ash ◽

Foliar Injury ◽

Visible Injury ◽

Geographical Variations ◽

Ecological Features ◽

Visible Foliar Injury

We compared leaf visible injury and physiological responses (gas exchange and chlorophyll a fluorescence) to high O3exposure (150 nmol mol–1h, 8 h day–1, 35–40 days) of two woody species of the same genus with different ecological features: the mesophilic green ash (Fraxinus excelsior) and the xerotolerant manna ash (F. ornus). We also studied how provenances from northern (Piedmont) and central (Tuscany) Italy, within the two species, responded to O3exposure. Onset and extent of visible foliar injury suggested thatF. excelsiorwas more O3sensitive thanF. ornus. The higher stomatal conductance inF. ornusthan inF. excelsiorsuggested a larger potential O3uptake, in disagreement to lower visible foliar injury. The higher carbon assimilation inF. ornussuggested a higher potential of O3detoxification and/or repair. Contrasting geographical variations of ash sensitivity to O3were recorded, as Piedmont provenances reduced gas exchange less than Tuscan provenances inF. excelsiorand more inF. ornus. Visible injury was earlier and more severe inF. excelsiorfrom Piedmont than from Tuscany, while the provenance did not affect visible injury onset and extent inF. ornus.

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Leaf Gas Exchange and Oxidative Stress in Sorghum Plants Supplied with Silicon and Infected by Colletotrichum sublineolum

Phytopathology ◽

10.1094/phyto-01-12-0014-r ◽

2012 ◽

Vol 102 (9) ◽

pp. 892-898 ◽

Cited By ~ 48

Author(s):

Renata Sousa Resende ◽

Fabrício Ávila Rodrigues ◽

Paulo Cezar Cavatte ◽

Samuel Cordeiro Vitor Martins ◽

Wiler Ribas Moreira ◽

...

Keyword(s):

Gas Exchange ◽

Carbon Fixation ◽

Leaf Gas Exchange ◽

Carbon Assimilation ◽

Colletotrichum Sublineolum ◽

Progress Curve ◽

Carbon Assimilation Rate ◽

Significant Difference ◽

Positive Effect ◽

And Oxidative Stress

Considering the economic importance of anthracnose, caused by Colletotrichum sublineolum, and silicon (Si) to enhance sorghum resistance against this disease, this study aimed to investigate the effect of this element on leaf gas exchange and also the antioxidative system when infected by C. sublineolum. Plants from sorghum line CMSXS142 (BR 009 [Tx623] – Texas), growing in hydroponic culture with (+Si, 2 mM) or without (–Si) Si, were inoculated with C. sublineolum. Disease severity was assessed at 2, 4, 6, 8, and 10 days after inoculation (dai) and data were used to calculate the area under anthracnose progress curve (AUAPC). Further, the net carbon assimilation rate (A), stomatal conductance to water vapor (gs), internal-to-ambient CO2 concentration ratio (Ci/Ca), and transpiration rate (E); the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR); the electrolyte leakage (EL), and the concentrations of hydrogen peroxide (H2O2) and malondialdehyde (MDA) were determined. The AUAPC was reduced by 86% for the +Si plants compared with the –Si plants. The values of A, gs, and E were lower upon inoculation of –Si plants in contrast to inoculated +Si plants with decreases of 31 and 60% for A, 34 and 61% for gs, and 27 and 57% for E, respectively, at 4 and 8 dai. For the noninoculated plants, there was no significant difference between the –Si and +Si treatments for the values of A, gs, and E. The Ci/Ca ratio was similar between the –Si and +Si treatments, regardless of the pathogen inoculation. The activities of SOD, CAT, APX, and GR tended to be higher in the +Si plants compared with the –Si plants upon inoculation with C. sublineolum. The EL significantly increased for –Si plants compared with +Si plants. The MDA concentration significantly increased by 31 and 38% at 4 and 8 dai, respectively, for the –Si plants compared with the +Si plants. Based on these results, Si may have a positive effect on sorghum physiology when infected by C. sublineolum through the maintenance of carbon fixation and also by enhancing the antioxidant system, which resulted in an increase in reactive oxygen species scavenging and, ultimately, reduced damage to the cell membranes.

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Assessment of six Indian cultivars of mung bean against ozone by using foliar injury index and changes in carbon assimilation, gas exchange, chlorophyll fluorescence and photosynthetic pigments

Environmental Monitoring and Assessment ◽

10.1007/s10661-013-3136-0 ◽

2013 ◽

Vol 185 (9) ◽

pp. 7793-7807 ◽

Cited By ~ 12

Author(s):

Nivedita Chaudhary ◽

Suruchi Singh ◽

S. B. Agrawal ◽

Madhoolika Agrawal

Keyword(s):

Chlorophyll Fluorescence ◽

Gas Exchange ◽

Photosynthetic Pigments ◽

Mung Bean ◽

Carbon Assimilation ◽

Foliar Injury ◽

Injury Index

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Stomatal and non-stomatal limitations on leaf carbon assimilation in beech (Fagus sylvatica L.) seedlings under natural conditions

Forest Systems ◽

10.5424/fs/2012213-02348 ◽

2012 ◽

Vol 21 (3) ◽

pp. 405 ◽

Cited By ~ 5

Author(s):

I. Aranda ◽

J. Rodríguez-Calcerrada ◽

T.M. Robson ◽

F.J. Cano ◽

L. Alté ◽

...

Keyword(s):

Fagus Sylvatica ◽

Carbon Assimilation ◽

Natural Conditions ◽

Fagus Sylvatica L ◽

Stomatal Limitations

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GAS EXCHANGE AND FERN WATER POTENTIALS OF WATER-STRESSED ASPARAGUS

HortScience ◽

10.21273/hortsci.25.9.1166g ◽

1990 ◽

Vol 25 (9) ◽

pp. 1166g-1167

Author(s):

Daniel Drost ◽

Darlene Wilcox-Lee

Keyword(s):

Soil Moisture ◽

Gas Exchange ◽

Carbon Assimilation ◽

Moisture Stress ◽

Carbon Dioxide Assimilation ◽

Soil Moisture Stress ◽

Drought Tolerant ◽

Water Potentials ◽

Intermediate Response ◽

Low Levels

Asparagus is considered a relatively drought tolerant plant, but few studies are available on the gas exchange response to soil moisture stress. Seedlings were grown in the greenhouse for six months before initiation of the water stress treatments. Soils were allowed to dry to matric potentials of -0.05, -0.3 and -0.5 MPa before rewatering to pot capacity. Gas exchange and fern water potentials were measured diurnally on asparagus plants when soil matric potentials reached their minima. Decreasing soil matric potentials decreased net carbon dioxide assimilation, stomatal conductance and fern water potential. Assimilation rates (6 am) were between 3 and 5 umols m-2 s-1 for all soil moisture treatments. Carbon assimilation rates of 10, 8, and 7 umols m-2 s-1 were recorded at 10 am for the -0.05, -0.3 and -0.5 MPa soil matric potentials, respectively. Assimilation rates decreased sharply over the remainder of the day. The diurnal pattern for conductance were similar to the assimilation rates. Fern water potentials were greater in the -0.05 MPa than in the -0.5 MPa treatment for all measurement periods with an intermediate response for soil matric potentials of -0.3 MPa. Fern water potentials were highest at 6 am (-0.2 to -0.6 MPa) before declining to their minima (-1.5 to -1.8 MPa) at 10 am. Water potentials remained at these low levels throughout the day before recovering slightly at 6 pm.

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502 Intermittent CO2 Enrichment for Hydroponic Lettuce Production

HortScience ◽

10.21273/hortsci.34.3.532a ◽

1999 ◽

Vol 34 (3) ◽

pp. 532A-532 ◽

Cited By ~ 1

Author(s):

David S. de Villiers ◽

Robert W. Langhans ◽

A.J. Both ◽

Louis D. Albright ◽

Sue Sue Scholl

Keyword(s):

Gas Exchange ◽

Carbon Assimilation ◽

Co2 Enrichment ◽

Biomass Accumulation ◽

Light Level ◽

Daily Light Integral ◽

Physiological Processes ◽

Light Levels ◽

Growth Increments ◽

Supplemental Lighting

CO2 enrichment increases efficiency of light utilization and rate of growth, thereby reducing the need for supplemental lighting and potentially lowering cost of production. However, during warmer periods of the year, CO2 enrichment is only possible intermittently due to the need to vent for temperature control. Previous research investigated the separate and combined effects of daily light integral and continuous CO2 enrichment on biomass accumulation in lettuce. The current research was designed to look at the efficiency with which lettuce is able to utilize intermittent CO2 enrichment, test the accuracy with which growth can be predicted and controlled, and examine effects of varying CO2 enrichment and supplemental lighting on carbon assimilation and plant transpiration on a minute by minute basis. Experiments included application of various schedules of intermittent CO2 enrichment and gas exchange analysis to elucidate underlying physiological processes. Same-day and day-to-day adjustments in daily light integrals were made in response to occasional CO2 venting episodes, using an up-to-the-minute estimate of growth progress based on an integration of growth increments that were calculated from actual light levels and CO2 concentrations experienced by the plants. Results indicated lettuce integrates periods of intermittent CO2 enrichment well, achieving expected growth targets as measured by destructive sampling. The gas-exchange work quantified a pervasive impact of instantaneous light level and CO2 concentration on conductance and CO2 assimilation. Implications for when to apply supplemental lighting and CO2 enrichment to best advantage and methods for predicting and controlling growth under intermittent CO2 enrichment are discussed.

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Cool Orchard Temperatures or Growing Trees in Containers Can Inhibit Leaf Gas Exchange of Avocado and Mango

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.124.1.46 ◽

1999 ◽

Vol 124 (1) ◽

pp. 46-51 ◽

Cited By ~ 18

Author(s):

Anthony W. Whiley ◽

Christopher Searle ◽

Bruce Schaffer ◽

B. Nigel Wolstenholme

Keyword(s):

Gas Exchange ◽

Leaf Gas Exchange ◽

Mangifera Indica ◽

Carbon Assimilation ◽

Persea Americana ◽

Quantum Yields ◽

Light Saturation ◽

Lower Maximum ◽

Root Restriction ◽

Stressed Field

Leaf gas exchange of avocado (Persea americana Mill.) and mango (Mangifera indica L.) trees in containers and in an orchard (field-grown trees) was measured over a range of photosynthetic photon fluxes (PPF) and ambient CO2 concentrations (Ca). Net CO2 assimilation (A) and intercellular partial pressure of CO2 (Ci) were determined for all trees in early autumn (noncold-stressed leaves) when minimum daily temperatures were ≥14 °C, and for field-grown trees in winter (cold-stressed leaves) when minimum daily temperatures were ≤10 °C. Cold-stressed trees of both species had lower maximum CO2 assimilation rates (Amax), light saturation points (QA), CO2 saturation points (CaSAT) and quantum yields than leaves of noncold-stressed, field-grown trees. The ratio of variable to maximum fluorescence (Fv/Fm) was ≈50% lower for leaves of cold-stressed, field-grown trees than for leaves of nonstressed, field-grown trees, indicating chill-induced photoinhibition of leaves had occurred in winter. The data indicate that chill-induced photoinhibition of A and/or sink limitations caused by root restriction in container-grown trees can limit carbon assimilation in avocado and mango trees.

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Simultaneous Effects of Foliar Nitrogen, Temperature, and Humidity on Gas Exchange in Pinus radiata

Functional Plant Biology ◽

10.1071/pp9950615 ◽

1995 ◽

Vol 22 (4) ◽

pp. 615 ◽

Cited By ~ 6

Author(s):

DW Sheriff ◽

JP Mattay

Keyword(s):

Gas Exchange ◽

Pinus Radiata ◽

Vapour Pressure ◽

Measurement Data ◽

Carbon Assimilation ◽

Vapour Pressure Deficit ◽

Leaf Temperature ◽

Carbon Gain ◽

Foliar Nitrogen ◽

Foliar N

Seedlings of Pinus radiata were grown in a glasshouse in large pots with sand as the potting mix. They were kept well-watered and frequently supplied with nutrient solutions which contained different amounts of nitrogen for different treatments. Carbon assimilation and diffusive conductance of the foliage were measured under steady-state conditions at saturating light in all treatments. Experimental variables were leaf-air vapour pressure difference and leaf temperature at time of measurement. Data were fitted to a non-linear regression equation to examine responses of carbon assimilation, diffusive conductance, transpiration, assimilatory nitrogen-use efficiency, and assimilatory transpiration efficiency to foliar nitrogen concentration expressed on a leaf area basis ([N]), to leaf temperature, and to leaf-air vapour pressure (D). Parameters from the regression have been used to plot three-dimensional surfaces, so that simultaneous effects of experimental variables can be easily visualised. Carbon assimilation increased linearly with foliar [N], declined exponentially as D increased, and had a broad temperature optimum between c. 14 and 38�C. Diffusive conductance increased linearly with foliar [N], was related to the reciprocal of D, and declined as temperature increased. Using climatic vapour pressure deficit and air temperature data for Canberra, ACT, and for Mount Gambier, SA, and with the functions that had been fitted to experimental data, it was found that these regional climatic differences have potential for appreciably affecting carbon gain and water loss in the regions, which have P. radiata plantations. Predicted differences in carbon gain are of the order of reported differences in stem growth in the regions. This shows the need to take into account regional variation in climatic variables that strongly affect gas exchange when investigating regional differences in productivity.

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