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Wieloch T, Sharkey TD, Werner RA, Schleucher J. Intramolecular carbon isotope signals reflect metabolite allocation in plants. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:2558-2575. [PMID: 35084456 PMCID: PMC9015809 DOI: 10.1093/jxb/erac028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 01/24/2022] [Indexed: 05/26/2023]
Abstract
Stable isotopes at natural abundance are key tools to study physiological processes occurring outside the temporal scope of manipulation and monitoring experiments. Whole-molecule carbon isotope ratios (13C/12C) enable assessments of plant carbon uptake yet conceal information about carbon allocation. Here, we identify an intramolecular 13C/12C signal at tree-ring glucose C-5 and C-6 and develop experimentally testable theories on its origin. More specifically, we assess the potential of processes within C3 metabolism for signal introduction based (inter alia) on constraints on signal propagation posed by metabolic networks. We propose that the intramolecular signal reports carbon allocation into major metabolic pathways in actively photosynthesizing leaf cells including the anaplerotic, shikimate, and non-mevalonate pathway. We support our theoretical framework by linking it to previously reported whole-molecule 13C/12C increases in cellulose of ozone-treated Betula pendula and a highly significant relationship between the intramolecular signal and tropospheric ozone concentration. Our theory postulates a pronounced preference for leaf cytosolic triose-phosphate isomerase to catalyse the forward reaction in vivo (dihydroxyacetone phosphate to glyceraldehyde 3-phosphate). In conclusion, intramolecular 13C/12C analysis resolves information about carbon uptake and allocation enabling more comprehensive assessments of carbon metabolism than whole-molecule 13C/12C analysis.
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Affiliation(s)
- Thomas Wieloch
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| | - Thomas David Sharkey
- MSU-DOE Plant Research Laboratory, Plant Resilience Institute, and Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Roland Anton Werner
- Department of Environmental Systems Science, ETH Zürich, Universitätstrasse 2, 8092 Zürich, Switzerland
| | - Jürgen Schleucher
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
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2
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Nickel UT, Weikl F, Kerner R, Schäfer C, Kallenbach C, Munch JC, Pritsch K. Quantitative losses vs. qualitative stability of ectomycorrhizal community responses to 3 years of experimental summer drought in a beech-spruce forest. GLOBAL CHANGE BIOLOGY 2018; 24:e560-e576. [PMID: 29063659 DOI: 10.1111/gcb.13957] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/08/2017] [Accepted: 10/11/2017] [Indexed: 06/07/2023]
Abstract
Forest ecosystems in central Europe are predicted to face an increasing frequency and severity of summer droughts because of global climate change. European beech and Norway spruce often coexist in these forests with mostly positive effects on their growth. However, their different below-ground responses to drought may lead to differences in ectomycorrhizal (ECM) fungal community composition and functions which we examined at the individual root and ecosystem levels. We installed retractable roofs over plots in Kranzberg Forest (11°39'42″E, 48°25'12″N; 490 m a.s.l.) to impose repeated summer drought conditions and assigned zones within each plot where trees neighboured the same or different species to study mixed species effects. We found that ECM fungal community composition changed and the numbers of vital mycorrhizae decreased for both tree species over 3 drought years (2014-2016), with the ECM fungal community diversity of beech exhibiting a faster and of spruce a stronger decline. Mixed stands had a positive effect on the ECM fungal community diversity of both tree species after the third drought year. Ectomycorrhizae with long rhizomorphs increased in both species under drought, indicating long-distance water transport. However, there was a progressive decline in the number of vital fine roots during the experiment, resulting in a strong reduction in enzyme activity per unit volume of soil. Hydrolytic enzyme activities of the surviving ectomycorrhizae were stable or stimulated upon drought, but there was a large decline in ECM fungal species with laccase activity, indicating a decreased potential to exploit nutrients bound to phenolic compounds. Thus, the ectomycorrhizae responded to repeated drought by maintaining or increasing their functionality at the individual root level, but were unable to compensate for quantitative losses at the ecosystem level. These findings demonstrate a strong below-ground impact of recurrent drought events in forests.
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Affiliation(s)
- Uwe T Nickel
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Allergens in Ecosystems, Neuherberg, Germany
| | - Fabian Weikl
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Allergens in Ecosystems, Neuherberg, Germany
| | - René Kerner
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Allergens in Ecosystems, Neuherberg, Germany
| | - Cynthia Schäfer
- Forest Growth and Yield Science, Technische Universität München, Freising, Germany
| | | | - Jean C Munch
- Grassland Science, Technische Universität München, Freising, Germany
| | - Karin Pritsch
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München, Allergens in Ecosystems, Neuherberg, Germany
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3
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Zang C, Hartl-Meier C, Dittmar C, Rothe A, Menzel A. Patterns of drought tolerance in major European temperate forest trees: climatic drivers and levels of variability. GLOBAL CHANGE BIOLOGY 2014; 20:3767-79. [PMID: 24838398 DOI: 10.1111/gcb.12637] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 05/12/2014] [Indexed: 05/22/2023]
Abstract
The future performance of native tree species under climate change conditions is frequently discussed, since increasingly severe and more frequent drought events are expected to become a major risk for forest ecosystems. To improve our understanding of the drought tolerance of the three common European temperate forest tree species Norway spruce, silver fir and common beech, we tested the influence of climate and tree-specific traits on the inter and intrasite variability in drought responses of these species. Basal area increment data from a large tree-ring network in Southern Germany and Alpine Austria along a climatic cline from warm-dry to cool-wet conditions were used to calculate indices of tolerance to drought events and their variability at the level of individual trees and populations. General patterns of tolerance indicated a high vulnerability of Norway spruce in comparison to fir and beech and a strong influence of bioclimatic conditions on drought response for all species. On the level of individual trees, low-growth rates prior to drought events, high competitive status and low age favored resilience in growth response to drought. Consequently, drought events led to heterogeneous and variable response patterns in forests stands. These findings may support the idea of deliberately using spontaneous selection and adaption effects as a passive strategy of forest management under climate change conditions, especially a strong directional selection for more tolerant individuals when frequency and intensity of summer droughts will increase in the course of global climate change.
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Affiliation(s)
- Christian Zang
- Chair of Ecoclimatology, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, Freising, 85354, Germany
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Kohut R, Flanagan C, Cheatham J, Porter E. Foliar Ozone Injury on Cutleaf Coneflower at Rocky Mountain National Park, Colorado. WEST N AM NATURALIST 2012. [DOI: 10.3398/064.072.0104] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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5
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Matyssek R, Le Thiec D, Löw M, Dizengremel P, Nunn AJ, Häberle KH. Interactions between drought and O3 stress in forest trees. PLANT BIOLOGY (STUTTGART, GERMANY) 2006; 8:11-7. [PMID: 16435265 DOI: 10.1055/s-2005-873025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Temperature increase and altered precipitation are facets of "Global Change", along with enhanced tropospheric ozone (O3) and CO2 levels. Both O3 and drought may curtail the probably limited capacity of "extra" carbon fixation in forest trees under a CO2-enriched atmosphere. In view of the exceptionally dry year of 2003 in Central Europe, this mini-review highlights O3/drought interactions in biochemical and ecophysiological responses of trees. Such interactions appear to vary, depending on the genotype and factorial scenarios. If O3 perturbs stomatal regulation, tolerance to both drought and persisting O3 exposure may be weakened, although drought preceding O3 stress may "harden" against O3 impact. Stomatal closure under drought may shield trees against O3 uptake and injury, which indeed was the case in 2003. However, the trees' "tuning" between O3 uptake and defence capacity is crucial in stress tolerance. Defence may be constrained due to limited carbon fixation, which results from the trade-off with O3 exclusion upon stomatal closure. Drought may cause a stronger reduction in stem growth than does ozone on an annual basis.
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Affiliation(s)
- R Matyssek
- Ecophysiology of Plants, Technische Universität München, Am Hochanger 13, 85354 Freising, Germany.
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6
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Fontaine V, Cabané M, Dizengremel P. Regulation of phosphoenolpyruvate carboxylase in Pinus halepensis needles submitted to ozone and water stress. PHYSIOLOGIA PLANTARUM 2003; 117:445-452. [PMID: 12675734 DOI: 10.1034/j.1399-3054.2003.00052.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Effects of ozone and/or drought stresses on phosphoenolpyruvate carboxylase (PEPc, EC 4.1.1.31) regulation in Pinus halepensis Mill. needles were assessed over 3 months in controlled conditions. Whereas moderated water stress applied to Aleppo pine had no effect on PEPc activity compared to the control, which was probably related to the high tolerance of this species to drought, ozone stress induced a dramatic increase of PEPc activity in pine needles. This stimulation of the anaplerotic pathway could provide substrates to repair processes, well known for being enhanced upon ozone exposure. The ozone-increased PEPc activity was related, to a certain extent, to an increase in protein and mRNA levels. The possible role of the stimulation of the phosphorylation status of the enzyme in the increased PEPc activity under ozone was also investigated. Following the demonstration of the existence of the phosphorylation site at the N terminal part of Aleppo pine PEPc, it was shown that, under ozone treatment, the light/dark PEPc activity ratio and the Ki (malate) for PEPc were increased. This strengthens the hypothesis of an ozone-related post-translational process, which could be part of an adaptation of the plants to prolonged stress. When ozone and water stress were applied in combination, the enhancement in PEPc activity was only related to changes in gene expression. This difference in PEPc regulation, compared to the effect of single stress, could be the consequence of the specific action of each stress on the enzyme. This study brings new insights into the regulation of PEPc in a C3 plant, Aleppo pine under these stresses. A different regulatory mechanism of PEPc is occurring according to the stress. The physiological implications of the increase in PEPc activity in response to ozone and/or water stress are discussed.
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Affiliation(s)
- Véronique Fontaine
- UMR 1137 INRA-UHP Nancy 1 'Ecologie et Ecophysiologie Forestières', BP 239, F-54506 Vandoeuvre les Nancy cedex, France Present address: School of Biochemistry and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
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7
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Manes F, Donato E, Vitale M. Physiological response of Pinus halepensis needles under ozone and water stress conditions. PHYSIOLOGIA PLANTARUM 2001; 113:249-257. [PMID: 12060303 DOI: 10.1034/j.1399-3054.2001.1130213.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The aim of this study was to evaluate how physiological processes of potted Pinus halepensis plants, grown under controlled conditions, were affected by ozone (O3) and/or water stress, integrating the gas exchange and biochemical data with fluorescence OJIP polyphasic transient data. Plants submitted to only water stress (T1) and with ozone (T3) showed a strong decrease in stomatal conductance and gas exchange, coinciding with a reduction of maximum yield of photochemistry (varphipo) and very negative values of leaf water potential. Simultaneously, a great increase of both PSII antenna size, indicated by absorption per reaction centre, and electron transport per reaction centre were found. The reduction of photosynthesis in the O3-treated plants (T2) by a slowing down of the Calvin cycle was supported by the increase of related fluorescence parameters such as relative variable fluorescence, heat de-excitation constant, energy de-excitation by spillover, and the decrease of varphipo. We suggest an antagonistic effect between the two stresses to explain the delayed ozone-induced decrease of stomatal conductance values for T3 with respect to T1 plants, by an alteration of the physiological mechanisms of stomatal opening, which involve the increase of intra-cellular free-calcium induced by ABA under co-occurring water shortage. We emphasise the importance of considering the intensity of the individual stress factor in studies concerning the interaction of stresses.
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Affiliation(s)
- Fausto Manes
- Department of Plant Biology, University of Rome 'La Sapienza', Piazzale Aldo Moro, 5, I-00185 Rome, Italy Department of Environmental Sciences, University of Molise, Via Giuseppe Mazzini, 8, I-86170 Isernia, Italy
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8
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Emberson LD, Wieser G, Ashmore MR. Modelling of stomatal conductance and ozone flux of Norway spruce: comparison with field data. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2000; 109:393-402. [PMID: 15092872 DOI: 10.1016/s0269-7491(00)00042-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/1999] [Accepted: 01/05/2000] [Indexed: 05/24/2023]
Abstract
It has been proposed that stomatal flux of ozone would provide a more reliable basis than ozone exposure indices for the assessment of the risk of ozone damage to vegetation across Europe. However, implementation of this approach requires the development of appropriate models which need to be rigorously tested against actual data collected under field conditions. This paper describes such an assessment of the stomatal component of the model described by Emberson et al. (2000. Modelling stomatal ozone flux across Europe. Environmental Pollution 110). Model predictions are compared with field measurements of both stomatal conductance (g(s)) and calculated ozone flux for shoots of mature Norway spruce (Picea abies) growing in the Tyrol Mountains in Austria. The model has been developed to calculate g(s) as a function of leaf phenology and four environmental variables: photosynthetic flux density (PFD), temperature, vapour pressure deficit (VPD) and soil moisture deficit (SMD). The model was run using climate data measured on site, although the SMD component was omitted since the necessary data were not available. The model parameterisation for Norway spruce had previously been collected from the scientific literature and therefore established independently from the measurement study. Overall, strong associations were found between model predictions and measured values of stomatal conductance to ozone (GO(3)) and calculated stomatal ozone flux (FO(3)). Average diurnal profiles of GO(3) and FO(3) showed good agreement between the field data and modelled values except during the morning period of 1990. The diurnal pattern of ozone flux was determined primarily by PFD and VPD, as there was little diurnal variation in ozone concentration. In general, the model predicted instances of high ozone flux satisfactorily, indicating its potential applicability in identifying areas of high ozone risk for this species.
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Affiliation(s)
- L D Emberson
- Stockholm Environment Institute at York, University of York, UK.
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Torsethaugen G, Pell EJ, Assmann SM. Ozone inhibits guard cell K+ channels implicated in stomatal opening. Proc Natl Acad Sci U S A 1999; 96:13577-82. [PMID: 10557363 PMCID: PMC23990 DOI: 10.1073/pnas.96.23.13577] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ozone (O3) deleteriously affects organisms ranging from humans to crop plants, yet little is understood regarding the underlying mechanisms. In plants, O3 decreases CO2 assimilation, but whether this could result from direct O3 action on guard cells remained unknown. Potassium flux causes osmotically driven changes in guard cell volume that regulate apertures of associated microscopic pores through which CO2 is supplied to the photosynthetic mesophyll tissue. We show in Vicia faba that O3 inhibits (i) guard cell K+ channels that mediate K+ uptake that drives stomatal opening; (ii) stomatal opening in isolated epidermes; and (iii) stomatal opening in leaves, such that CO2 assimilation is reduced without direct effects of O3 on photosynthetic capacity. Direct O3 effects on guard cells may have ecological and agronomic implications for plant productivity and for response to other environmental stressors including drought.
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Affiliation(s)
- G Torsethaugen
- Environmental Resources Research Institute, Pennsylvania State University, University Park, PA 16802, USA
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10
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Influence of Drought Stress on the Response of Shortleaf Pine to Ozone. ACTA ACUST UNITED AC 1998. [DOI: 10.1007/978-1-4612-2178-4_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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11
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Matyssek R, Havranek WM, Wieser G, Innes JL. Ozone and the Forests in Austria and Switzerland. FOREST DECLINE AND OZONE 1997. [DOI: 10.1007/978-3-642-59233-1_4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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12
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Chappelka AH, Freer-Smith PH. Predisposition of trees by air pollutants to low temperatures and moisture stress. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 1995; 87:105-117. [PMID: 15091613 DOI: 10.1016/s0269-7491(99)80013-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/1993] [Accepted: 11/30/1993] [Indexed: 05/24/2023]
Abstract
Air pollution can have direct effects on trees. It can cause visible injury to foliage and a disruption of physiological processes, such as photosynthesis and carbon allocation, leading to losses in growth and productivity. This review suggests that of equal or greater importance is the potential of air pollutants to indirectly affect tree growth and vitality by predisposing them to injury from other abiotic and biotic stresses. Predisposition by air pollutants can be the result of a disruption in biochemical processes, such as enzyme activity or production, or physiological factors (e.g. stomatal closure, carbon allocation). Air pollutants such as SO(2), O(3) and acidic mists have been implicated as predisposing agents to two of the most important of these stresses: low temperature and soil moisture. Probable mechanisms, as well as implications of predicted changes in global climate will be discussed.
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Affiliation(s)
- A H Chappelka
- School of Forestry, Alabama Agricultural Experiment Station, Auburn University, Auburn, AL 36849, USA
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13
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Grüters U, Fangmeier A, Jäger HJ. Modelling stomatal responses of spring wheat (Triticum aestivum L. cv. Turbo) to ozone and different levels of water supply. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 1995; 87:141-149. [PMID: 15091587 DOI: 10.1016/0269-7491(94)p2600-e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/1993] [Accepted: 01/17/1994] [Indexed: 05/24/2023]
Abstract
Spring wheat (Triticum aestivum L. cv. Turbo) was exposed to different levels of ozone and water supply in open-top chambers in 1991. Air was charcoal filtered (CF), non-filtered (NF) and CF plus proportional addition of ambient or twice ambient ozone (CF1, CF2). Seasonal means of O(3), taken over 24 h, were 2.3, 20.6, 17.3, and 34.5 nl litre(-1) for CF, NF, CF1 and CF2 treatments, respectively. A split-plot design was used to obtain two levels of water supply: one-half of the pots was irrigated sufficiently not to show any symptoms of drought stress; the others were exposed to low water supply and received 50% of these amounts. Using a steady-state porometer approximately 800 measurements of stomatal conductance (g(s)) were made on flag leaves from 68 to 106 days after sowing. The measurements yielded only small differences of maximum conductance between the two levels of water supply. Therefore, low water supply did not protect wheat plants against ozone injury via reduced stomatal uptake in this experiment. To describe the effects of environmental variables on the stomatal behaviour, boundary-line analysis and non-linear regression analysis were used. Besides microclimatic parameters, the ozone dose of flag leaves was introduced as an independent variable affecting stomatal aperture. A well-defined boundary line for ozone dose was found, suggesting that increasing ozone dose caused stomatal closure in wheat flag leaves. But at high ozone doses, co-acting senescence seems also responsible for the decrease in stomatal conductance. A multiplicative boundary-line model was used to predict stomatal conductance from combinations of environmental variables. In the test carried out with the measurements of stomatal conductance, the model accounted only for 40% of the variation of g(s). Generalized stomatal response patterns of the herbaceous growth form, the dependence of the variables' age and ozone dose and the lack of an important factor influencing stomatal response (water status of the plant) in the model, are suggested as explanations of the poor results of the test.
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Affiliation(s)
- U Grüters
- Institut für Pflanzenökologie, Heinrich-Buff-Ring 38, D-35392 Giessen, Germany
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14
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Beyers JL, Riechers GH, Temple PJ. Effects of long-term ozone exposure and drought on the photosynthetic capacity of ponderosa pine (Pinus ponderosa Laws.). THE NEW PHYTOLOGIST 1992; 122:81-90. [PMID: 33874044 DOI: 10.1111/j.1469-8137.1992.tb00055.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Seedlings of ponderosa pine (Pinus ponderosa Laws.) were grown for three years under three atmospheric ozone concentrations - clean air (CF), ambient ozone (NF), and 15 times ambient ozone (NF150)-at a moderately-polluted site in the Sierra Nevada, under either well-watered or drought-stressed conditions. When the trees were 5 years old, photosynthetic capacities of 2-year-old, 1-year-old, and current-year needles were measured during August and September of the 3rd season of exposure. Current-year needles of NF150 trees had higher photosynthetic capacity than NF and CF trees during late summer, an effect due to greatly enhanced photosynthesis in well-watered plants that had lost older needles as a result of ozone damage. This photosynthetic compensation in well-watered NF150 seedlings was related to higher tissue nitrogen concentration in the current-year foliage and possibly to increased inorganic phosphate cycling, both responses to the loss of older needles. Drought-stressed NF150 seedlings were partially protected from ozone damage by decreased stomatal conductance and did not exhibit the same degree of photosynthetic compensation. No differences in photosynthetic rate were found between CF and NF seedlings or between well-watered and drought-stressed seedlings (across ozone treatments) in any needle age class.
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Affiliation(s)
- Jan L Beyers
- Statewide Air Pollution Research Center, University of California, Riverside, CA 92521-0312 USA
| | - George H Riechers
- Statewide Air Pollution Research Center, University of California, Riverside, CA 92521-0312 USA
| | - Patrick J Temple
- Statewide Air Pollution Research Center, University of California, Riverside, CA 92521-0312 USA
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