1
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Guo JS, Barnes ML, Smith WK, Anderegg WRL, Kannenberg SA. Dynamic regulation of water potential in Juniperus osteosperma mediates ecosystem carbon fluxes. THE NEW PHYTOLOGIST 2024; 243:98-110. [PMID: 38725410 DOI: 10.1111/nph.19805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 04/14/2024] [Indexed: 06/07/2024]
Abstract
Some plants exhibit dynamic hydraulic regulation, in which the strictness of hydraulic regulation (i.e. iso/anisohydry) changes in response to environmental conditions. However, the environmental controls over iso/anisohydry and the implications of flexible hydraulic regulation for plant productivity remain unknown. In Juniperus osteosperma, a drought-resistant dryland conifer, we collected a 5-month growing season time series of in situ, high temporal-resolution plant water potential ( Ψ ) and stand gross primary productivity (GPP). We quantified the stringency of hydraulic regulation associated with environmental covariates and evaluated how predawn water potential contributes to empirically predicting carbon uptake. Juniperus osteosperma showed less stringent hydraulic regulation (more anisohydric) after monsoon precipitation pulses, when soil moisture and atmospheric demand were high, and corresponded with GPP pulses. Predawn water potential matched the timing of GPP fluxes and improved estimates of GPP more strongly than soil and/or atmospheric moisture, notably resolving GPP underestimation before vegetation green-up. Flexible hydraulic regulation appears to allow J. osteosperma to prolong soil water extraction and, therefore, the period of high carbon uptake following monsoon precipitation pulses. Water potential and its dynamic regulation may account for why process-based and empirical models commonly underestimate the magnitude and temporal variability of dryland GPP.
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Affiliation(s)
- Jessica S Guo
- Arizona Experiment Station, University of Arizona, Tucson, AZ, 85721, USA
| | - Mallory L Barnes
- O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, IN, 47405, USA
| | - William K Smith
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, 85721, USA
| | - William R L Anderegg
- School of Biological Sciences and Wilkes Center for Climate Science and Policy, University of Utah, Salt Lake City, UT, 84112, USA
| | - Steven A Kannenberg
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, 805023, USA
- Department of Biology, West Virginia University, Morgantown, WV, 26506, USA
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2
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Castillo-Argaez R, Sapes G, Mallen N, Lippert A, John GP, Zare A, Hammond WM. Spectral ecophysiology: hyperspectral pressure-volume curves to estimate leaf turgor loss. THE NEW PHYTOLOGIST 2024; 242:935-946. [PMID: 38482720 DOI: 10.1111/nph.19669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 02/19/2024] [Indexed: 04/12/2024]
Abstract
Turgor loss point (TLP) is an important proxy for plant drought tolerance, species habitat suitability, and drought-induced plant mortality risk. Thus, TLP serves as a critical tool for evaluating climate change impacts on plants, making it imperative to develop high-throughput and in situ methods to measure TLP. We developed hyperspectral pressure-volume curves (PV curves) to estimate TLP using leaf spectral reflectance. We used partial least square regression models to estimate water potential (Ψ) and relative water content (RWC) for two species, Frangula caroliniana and Magnolia grandiflora. RWC and Ψ's model for each species had R2 ≥ 0.7 and %RMSE = 7-10. We constructed PV curves with model estimates and compared the accuracy of directly measured and spectra-predicted TLP. Our findings indicate that leaf spectral measurements are an alternative method for estimating TLP. F. caroliniana TLP's values were -1.62 ± 0.15 (means ± SD) and -1.62 ± 0.34 MPa for observed and reflectance predicted, respectively (P > 0.05), while M. grandiflora were -1.78 ± 0.34 and -1.66 ± 0.41 MPa (P > 0.05). The estimation of TLP through leaf reflectance-based PV curves opens a broad range of possibilities for future research aimed at understanding and monitoring plant water relations on a large scale with spectral ecophysiology.
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Affiliation(s)
| | - Gerard Sapes
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
| | - Nicole Mallen
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
| | - Alston Lippert
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
| | - Grace P John
- Department of Biology, University of Florida, Gainesville, FL, 32611, USA
| | - Alina Zare
- Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL, 32611, USA
| | - William M Hammond
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
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3
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Mercado-Reyes JA, Pereira TS, Manandhar A, Rimer IM, McAdam SAM. Extreme drought can deactivate ABA biosynthesis in embolism-resistant species. PLANT, CELL & ENVIRONMENT 2024; 47:497-510. [PMID: 37905689 DOI: 10.1111/pce.14754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 08/24/2023] [Accepted: 10/18/2023] [Indexed: 11/02/2023]
Abstract
The phytohormone abscisic acid (ABA) is synthesised by plants during drought to close stomata and regulate desiccation tolerance pathways. Conifers and some angiosperms with embolism-resistant xylem show a peaking-type (p-type) response in ABA levels, in which ABA levels increase early in drought then decrease as drought progresses, declining to pre-stressed levels. The mechanism behind this dynamic remains unknown. Here, we sought to characterise the mechanism driving p-type ABA dynamics in the conifer Callitris rhomboidea and the highly drought-resistant angiosperm Umbellularia californica. We measured leaf water potentials (Ψl ), stomatal conductance, ABA, conjugates and phaseic acid (PA) levels in potted plants during a prolonged but non-fatal drought. Both species displayed a p-type ABA dynamic during prolonged drought. In branches collected before and after the peak in endogenous ABA levels in planta, that were rehydrated overnight and then bench dried, ABA biosynthesis was deactivated beyond leaf turgor loss point. Considerable conversion of ABA to conjugates was found to occur during drought, but not catabolism to PA. The mechanism driving the decline in ABA levels in p-type species may be conserved across embolism-resistant seed plants and is mediated by sustained conjugation of ABA and the deactivation of ABA accumulation as Ψl becomes more negative than turgor loss.
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Affiliation(s)
- Joel A Mercado-Reyes
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, USA
| | - Talitha Soares Pereira
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, USA
| | - Anju Manandhar
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, USA
| | - Ian M Rimer
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, USA
| | - Scott A M McAdam
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, USA
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4
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Tang S, Lin X, Li W, Guo C, Han J, Yu L. Nutrient resorption responses of female and male Populus cathayana to drought and shade stress. PHYSIOLOGIA PLANTARUM 2023; 175:e13980. [PMID: 37616009 DOI: 10.1111/ppl.13980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/03/2023] [Accepted: 07/14/2023] [Indexed: 08/25/2023]
Abstract
Nutrient resorption can increase nutrient use and play important roles in terrestrial plant nutrient cycles. Although several studies have reported individual responses of plant nutrient resorption to drought or shade stress, the interaction of drought and shade remains unclear, especially for dioecious plants. This study explored whether nutrient resorption is correlated to growth characteristics (such as biomass and root/shoot ratio [R/S ratio]) and leaf economics (such as leaf thickness, leaf mass per area [LMA] and leaf vein density [LVD]) in female and male Populus cathayana across different conditions. We found that drought stress significantly increased nitrogen (N) resorption efficiency (NRE) in both sexes, but shade and interactive stress decreased NRE in P. cathayana females. Under drought stress, nutrient resorption was sexually dimorphic such that P. cathayana males have higher NRE than females. Furthermore, NRE and phosphorous (P) resorption efficiency (PRE) were positively related to R/S ratio, leaf thickness, LMA, and LVD in both sexes across different treatments. Our study is the first to present how nutrient resorption is related to biomass accumulation and allocation, and leaf economics, suggesting that nutrient uptake may be modulated by R/S ratio and leaf economics, which is important for understanding the conservation mechanism of plant nutrients.
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Affiliation(s)
- Shuanglei Tang
- Department of Ecology, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Xiazhen Lin
- Teaching Center, Zhejiang Open University, Hangzhou, China
| | - Wen Li
- Department of Ecology, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Chengjin Guo
- Department of Ecology, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Jungang Han
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Wuhan University, Wuhan, China
- Department of Central Laboratory, Affiliated Hospital of Jiaxing University, Jiaxing, China
| | - Lei Yu
- Department of Ecology, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
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5
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Bi MH, Jiang C, Brodribb T, Yang YJ, Yao GQ, Jiang H, Fang XW. Ethylene constrains stomatal reopening in Fraxinus chinensis post moderate drought. TREE PHYSIOLOGY 2023; 43:883-892. [PMID: 36547259 DOI: 10.1093/treephys/tpac144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 12/01/2022] [Accepted: 12/11/2022] [Indexed: 06/11/2023]
Abstract
Clarifying the mechanisms underlying the recovery of gas exchange following drought is the key to providing insights into plant drought adaptation and habitat distribution. However, the mechanisms are still largely unknown. Targeting processes known to inhibit gas exchange during drought recovery, we measured leaf water potential, the leaf hydraulic conductance, stomatal reopening, abscisic acid (ABA) and the ethylene emission rate (EER) following moderate drought stress in seedlings of the globally pervasive woody tree Fraxinus chinensis. We found strong evidence that the slow stomatal reopening after rehydration is regulated by a slow decrease in EER, rather than changes in leaf hydraulics or foliar ABA levels. This was supported by evidence of rapid gas exchange recovery in plants after treatment with the ethylene antagonist 1-methylcyclopropene. These findings provide evidence to rigorously support ethylene as a key factor constraining stomatal reopening from moderate drought directly, thereby potentially opening new windows for understanding species drought adaptation.
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Affiliation(s)
- Min-Hui Bi
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Chao Jiang
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Timothy Brodribb
- School of Biological Sciences, University of Tasmania, Hobart, TAS 7001, Australia
| | - Yu-Jie Yang
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Guang-Qian Yao
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Hui Jiang
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Xiang-Wen Fang
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
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6
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Jin Y, Hao G, Hammond WM, Yu K, Liu X, Ye Q, Zhou Z, Wang C. Aridity-dependent sequence of water potentials for stomatal closure and hydraulic dysfunctions in woody plants. GLOBAL CHANGE BIOLOGY 2023; 29:2030-2040. [PMID: 36655297 DOI: 10.1111/gcb.16605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 01/01/2023] [Indexed: 05/28/2023]
Abstract
The sequence of physiological events during drought strongly impacts plants' overall performance. Here, we synthesized the global data of stomatal and hydraulic traits in leaves and stems of 202 woody species to evaluate variations in the water potentials for key physiological events and their sequence along the climatic gradient. We found that the seasonal minimum water potential, turgor loss point, stomatal closure point, and leaf and stem xylem vulnerability to embolism were intercorrelated and decreased with aridity, indicating that water stress drives trait co-selection. In xeric regions, the seasonal minimum water potential occurred at lower water potential than turgor loss point, and the subsequent stomatal closure delayed embolism formation. In mesic regions, however, the seasonal minimum water potential did not pose a threat to the physiological functions, and stomatal closure occurred even at slightly more negative water potential than embolism. Our study demonstrates that the sequence of water potentials for physiological dysfunctions of woody plants varies with aridity, that is, xeric species adopt a more conservative sequence to prevent severe tissue damage through tighter stomatal regulation (isohydric strategy) and higher embolism resistance, while mesic species adopt a riskier sequence via looser stomatal regulation (anisohydric strategy) to maximize carbon uptake at the cost of hydraulic safety. Integrating both aridity-dependent sequence of water potentials for physiological dysfunctions and gap between these key traits into the hydraulic framework of process-based vegetation models would improve the prediction of woody plants' responses to drought under global climate change.
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Affiliation(s)
- Ying Jin
- Key Laboratory of Sustainable Forest Ecosystem Management, Center for Ecological Research, Ministry of Education, Northeast Forestry University, Harbin, China
| | - Guangyou Hao
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - William M Hammond
- Agronomy Department, University of Florida, Gainesville, Florida, USA
| | - Kailiang Yu
- Department of Ecology & Evolutionary Biology, High Meadows Environmental Institute, Princeton University, Princeton, New Jersey, USA
| | - Xiaorong Liu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Qing Ye
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Zhenghu Zhou
- Key Laboratory of Sustainable Forest Ecosystem Management, Center for Ecological Research, Ministry of Education, Northeast Forestry University, Harbin, China
| | - Chuankuan Wang
- Key Laboratory of Sustainable Forest Ecosystem Management, Center for Ecological Research, Ministry of Education, Northeast Forestry University, Harbin, China
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7
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Napier JD, Heckman RW, Juenger TE. Gene-by-environment interactions in plants: Molecular mechanisms, environmental drivers, and adaptive plasticity. THE PLANT CELL 2023; 35:109-124. [PMID: 36342220 PMCID: PMC9806611 DOI: 10.1093/plcell/koac322] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 11/03/2022] [Indexed: 05/13/2023]
Abstract
Plants demonstrate a broad range of responses to environmental shifts. One of the most remarkable responses is plasticity, which is the ability of a single plant genotype to produce different phenotypes in response to environmental stimuli. As with all traits, the ability of plasticity to evolve depends on the presence of underlying genetic diversity within a population. A common approach for evaluating the role of genetic variation in driving differences in plasticity has been to study genotype-by-environment interactions (G × E). G × E occurs when genotypes produce different phenotypic trait values in response to different environments. In this review, we highlight progress and promising methods for identifying the key environmental and genetic drivers of G × E. Specifically, methodological advances in using algorithmic and multivariate approaches to understand key environmental drivers combined with new genomic innovations can greatly increase our understanding about molecular responses to environmental stimuli. These developing approaches can be applied to proliferating common garden networks that capture broad natural environmental gradients to unravel the underlying mechanisms of G × E. An increased understanding of G × E can be used to enhance the resilience and productivity of agronomic systems.
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Affiliation(s)
- Joseph D Napier
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, 78712, USA
| | - Robert W Heckman
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, 78712, USA
| | - Thomas E Juenger
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, 78712, USA
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8
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McAdam SAM, Kane CN, Mercado Reyes JA, Cardoso AA, Brodribb TJ. An abrupt increase in foliage ABA levels on incipient leaf death occurs across vascular plants. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:1262-1271. [PMID: 35238139 DOI: 10.1111/plb.13404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
Forest mortality during drought has been attributed to hydraulic failure, which can be challenging to measure. A limited number of alternative proxies for incipient leaf death exist. Here we investigate whether a terminal increase in abscisic acid (ABA) levels in leaves occurs across vascular land plants and is an indicator of imminent leaf death. For different species across vascular plants, we monitored ABA levels during lethal drought as well as leaf embolism resistance, across the canopy as leaves die following senescence, or when leaves are exposed to a heavy, lethal frost late in the growing season. We observed a considerable increase in foliage ABA levels once leaves showed signs of incipient leaf death. This increase in ABA levels upon incipient leaf death, could be induced by embolism during drought, by freezing or as leaves age naturally, and was observed in species spanning the phylogeny of vascular land plants as well as in an ABA biosynthetic mutant plant. A considerable increase in foliage ABA levels may act as an indicator of impending leaf death.
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Affiliation(s)
- S A M McAdam
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - C N Kane
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - J A Mercado Reyes
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - A A Cardoso
- Instituto de Ciências da Natureza, Universidade Federal de Alfenas, Alfenas, Brazil
| | - T J Brodribb
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
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9
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You Y, Ju C, Wang L, Wang X, Ma F, Wang G, Wang Y. The mechanism of arbuscular mycorrhizal enhancing cadmium uptake in Phragmites australis depends on the phosphorus concentration. JOURNAL OF HAZARDOUS MATERIALS 2022; 440:129800. [PMID: 36027745 DOI: 10.1016/j.jhazmat.2022.129800] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/31/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) is a vital strategy to enhance the phytoremediation of cadmium (Cd) pollution. However, the function of AMF was influenced by phosphorus (P) concentration. To reveal the effect of AMF on the Cd accumulation of host plants under different P concentrations and how the AMF and P interact, this study comparatively analyzed the regulatory effects of AMF on the Cd response, extraction, and transportation processes of Phragmites australis (P. australis) under different P levels, and explored its physiological, biochemical and molecular biological mechanisms. The study showed that AMF could induce different growth allocation strategies in response to Cd stress. Moreover, AMF promoted plant Cd tolerance and detoxification by enhancing P uptake, Cd passivation, Cd retention in the cell wall, and functional group modulation. Under P starvation treatments, AMF promoted Cd uptake by inducing Cd to enter the iron pathway, increased the transport coefficient by 493.39%, and retained Cd in stems. However, these effects disappeared following the addition of P. Additionally, AMF up-regulated the expression of ZIP, ZIP, and NRAMP genes to promote cadmium uptake at low, medium, and high phosphorus levels, respectively. Thus, the Cd response mechanism of the AMF-P. australis symbiotic system was P dose-dependent.
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Affiliation(s)
- Yongqiang You
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No. 73, Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Chang Ju
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No. 73, Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Li Wang
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No. 73, Huanghe Road, Nangang District, Harbin 150090, PR China.
| | - Xin Wang
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No. 73, Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Fang Ma
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No. 73, Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Gen Wang
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No. 73, Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Yujiao Wang
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No. 73, Huanghe Road, Nangang District, Harbin 150090, PR China
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10
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Chen Z, Li S, Wan X, Liu S. Strategies of tree species to adapt to drought from leaf stomatal regulation and stem embolism resistance to root properties. FRONTIERS IN PLANT SCIENCE 2022; 13:926535. [PMID: 36237513 PMCID: PMC9552884 DOI: 10.3389/fpls.2022.926535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
Considerable evidences highlight the occurrence of increasing widespread tree mortality as a result of global climate change-associated droughts. However, knowledge about the mechanisms underlying divergent strategies of various tree species to adapt to drought has remained remarkably insufficient. Leaf stomatal regulation and embolism resistance of stem xylem serves as two important strategies for tree species to prevent hydraulic failure and carbon starvation, as comprising interconnected physiological mechanisms underlying drought-induced tree mortality. Hence, the physiological and anatomical determinants of leaf stomatal regulation and stems xylem embolism resistance are evaluated and discussed. In addition, root properties related to drought tolerance are also reviewed. Species with greater investment in leaves and stems tend to maintain stomatal opening and resist stem embolism under drought conditions. The coordination between stomatal regulation and stem embolism resistance are summarized and discussed. Previous studies showed that hydraulic safety margin (HSM, the difference between minimum water potential and that causing xylem dysfunction) is a significant predictor of tree species mortality under drought conditions. Compared with HSM, stomatal safety margin (the difference between water potential at stomatal closure and that causing xylem dysfunction) more directly merge stomatal regulation strategies with xylem hydraulic strategies, illustrating a comprehensive framework to characterize plant response to drought. A combination of plant traits reflecting species' response and adaptation to drought should be established in the future, and we propose four specific urgent issues as future research priorities.
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Affiliation(s)
- Zhicheng Chen
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Shan Li
- Department of Environmental Science and Ecology, School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi’an, China
| | - Xianchong Wan
- Institute of Ecological Conservation and Restoration, Chinese Academy of Forestry, Beijing, China
| | - Shirong Liu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
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11
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Perera-Castro AV, González-Rodríguez ÁM, Fernández-Marín B. When time is not of the essence: constraints to the carbon balance of bryophytes. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4562-4575. [PMID: 35298628 DOI: 10.1093/jxb/erac104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 03/10/2022] [Indexed: 06/14/2023]
Abstract
The data available so far indicate that the photosynthetic and relative growth rates of bryophytes are 10% of those reported for tracheophytes. By examining the existing literature and reanalysing data published in over 100 studies, this review examines the ecophysiological, biochemical, and structural reasons behind this phenomenon. The limiting Rubisco content and surface for gas exchange are the internal factors that can explain the low photosynthetic and growth rates of bryophytes. The role of the thicker cell walls of bryophytes in limiting CO2 diffusion is unclear, due to the current uncertainties regarding their porosity and permeability to CO2. From this review, it is also evident that, despite bryophytes having low photosynthetic rates, their positive carbon balance is tightly related to their capacity to deal with extreme conditions. Contributing factors include their capacity to deal with large daily temperature oscillations, and their capacity to delay the cessation of photosynthesis under water deficit (or to tolerate desiccation in extreme situations). Although further studies on bryophytes are needed before more solid conclusions can be drawn, it seems that their success relies on their remarkable tolerance to a highly variable environment, possibly at the expense of their maximum photosynthetic rate.
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Affiliation(s)
- Alicia V Perera-Castro
- Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna, 38200 La Laguna, Canary Islands, Spain
| | - Águeda M González-Rodríguez
- Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna, 38200 La Laguna, Canary Islands, Spain
| | - Beatriz Fernández-Marín
- Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna, 38200 La Laguna, Canary Islands, Spain
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12
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Limousin JM, Roussel A, Rodríguez-Calcerrada J, Torres-Ruiz JM, Moreno M, Garcia de Jalon L, Ourcival JM, Simioni G, Cochard H, Martin-StPaul N. Drought acclimation of Quercus ilex leaves improves tolerance to moderate drought but not resistance to severe water stress. PLANT, CELL & ENVIRONMENT 2022; 45:1967-1984. [PMID: 35394675 DOI: 10.1111/pce.14326] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 03/12/2022] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
Increasing temperature and drought can result in leaf dehydration and defoliation even in drought-adapted tree species such as the Mediterranean evergreen Quercus ilex L. The stomatal regulation of leaf water potential plays a central role in avoiding this phenomenon and is constrained by a suite of leaf traits including hydraulic conductance and vulnerability, hydraulic capacitance, minimum conductance to water vapour, osmotic potential and cell wall elasticity. We investigated whether the plasticity in these traits may improve leaf tolerance to drought in two long-term rainfall exclusion experiments in Mediterranean forests. Osmotic adjustment was observed to lower the water potential at turgor loss in the rainfall-exclusion treatments, thus suggesting a stomatal closure at more negative water potentials and a more anisohydric behaviour in drier conditions. Conversely, leaf hydraulic conductance and vulnerability did not exhibit any plasticity between treatments so the hydraulic safety margins were narrower in the rainfall-exclusion treatments. The sequence of leaf responses to seasonal drought and dehydration was conserved among treatments and sites but trees were more likely to suffer losses of turgor and hydraulic functioning in the rainfall-exclusion treatments. We conclude that leaf plasticity might help the trees to tolerate moderate drought but not to resist severe water stress.
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Affiliation(s)
| | - Amélie Roussel
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Jesús Rodríguez-Calcerrada
- Departamento de Sistemas y Recursos Naturales, ETSI Montes, Forestal y del Medio Natural, Universidad Politécnica de Madrid Ciudad Universitaria, Madrid, Spain
| | | | - Myriam Moreno
- Unité Ecologie des Forêts Méditerranéennes (UR629), INRAE Avignon Cedex 9, Domaine Saint Paul, Site Agroparc, France
| | | | | | - Guillaume Simioni
- Unité Ecologie des Forêts Méditerranéennes (UR629), INRAE Avignon Cedex 9, Domaine Saint Paul, Site Agroparc, France
| | - Hervé Cochard
- PIAF, University Clermont-Auvergne, INRAE, Clermont-Ferrand, France
| | - Nicolas Martin-StPaul
- Unité Ecologie des Forêts Méditerranéennes (UR629), INRAE Avignon Cedex 9, Domaine Saint Paul, Site Agroparc, France
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13
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Hu Y, Xiang W, Schäfer KVR, Lei P, Deng X, Forrester DI, Fang X, Zeng Y, Ouyang S, Chen L, Peng C. Photosynthetic and hydraulic traits influence forest resistance and resilience to drought stress across different biomes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 828:154517. [PMID: 35278541 DOI: 10.1016/j.scitotenv.2022.154517] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/07/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
Drought events lead to depressions in gross primary productivity (GPP) of forest ecosystems. Photosynthetic and hydraulic traits are important factors governing GPP variation. However, how these functional traits affect GPP responses to drought has not been well understood. We quantified the capacity of GPP to withstand changes during droughts (GPP_resistance) and its post-drought responses (GPP_resilience) using eddy covariance data from the FLUXNET2015 dataset, and investigated how functional traits of dominant tree species that comprised >80% of the biomass (or composition) influenced GPP_resistance or GPP_resilience. Light-saturated photosynthetic rate of dominant tree species was negatively related to GPP_resistance, and was positively correlated with GPP_resilience. Forests dominated by species with higher hydraulic safety margins (HSM), smaller vessel diameter (Vdia) and lower sensitivity of canopy stomatal conductance per unit land area (Gs) to droughts had a higher GPP_resistance, while those dominated by species with lower HSM, larger Vdia and higher sensitivity of Gs to droughts exhibited a higher GPP_resilience. Differences in functional traits of forests located in diverse climate regions led to distinct GPP sensitivities to droughts. Forests located in humid regions had a higher GPP_resilience while those in arid regions exhibited a higher GPP_resistance. Forest GPP_resistance was negatively related to drought intensity, and GPP_resilience was negatively related to drought duration. Our findings highlight the significant role of functional traits in governing forest resistance and resilience to droughts. Overall, forests dominated by species with higher hydraulic safety were more resistant to droughts, while forests containing species with higher photosynthetic and hydraulic efficiency recovered better from drought stress.
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Affiliation(s)
- Yanting Hu
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China
| | - Wenhua Xiang
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China.
| | - Karina V R Schäfer
- Department of Earth and Environmental Sciences, Rutgers University, 195 University Avenue, Newark 07102, NJ, USA
| | - Pifeng Lei
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China
| | - Xiangwen Deng
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China
| | - David I Forrester
- Swiss Federal Institute of Forest Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Xi Fang
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China
| | - Yelin Zeng
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China
| | - Shuai Ouyang
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China
| | - Liang Chen
- Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China
| | - Changhui Peng
- Department of Biological Sciences, Institute of Environment Sciences, University of Quebec at Montreal, Montreal, Quebec H3C 3P8, Canada
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14
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Saunders A, Drew DM. Stomatal responses of Eucalyptus spp. under drought can be predicted with a gain-risk optimization model. TREE PHYSIOLOGY 2022; 42:815-830. [PMID: 34791492 DOI: 10.1093/treephys/tpab145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/05/2021] [Indexed: 06/13/2023]
Abstract
The frequency and severity of drought events are expected to increase due to climate change, with optimal environmental conditions for forestry likely to shift. Modeling plant responses to a changing climate is therefore vital. We tested the process-based gain-risk model to predict stomatal responses to drought of two Eucalyptus hybrids. The process-based gain-risk model has the advantage that all the parameters used within the model are based on measurable plant traits. The gain-risk model proposes that plants optimize photosynthetic gain while minimizing a hydraulic cost. Previous versions of the model used hydraulic risk as a cost function; however, they did not account for delayed or reduced hydraulic recovery rates from embolism post-drought. Hydraulic recovery has been seen in many species, however it is still unclear how this inclusion of a partial or delayed hydraulic recovery would affect the predictive power of the gain-risk model. Many hydraulic parameters required by the model are also difficult to measure and are not freely available. We therefore tested a simplified gain-risk model that includes a delayed or reduced hydraulic recovery component post-drought. The simplified gain-risk model performed well at predicting stomatal responses in both Eucalyptus grandis × camaldulensis (GC) and Eucalyptus urophylla × grandis (UG). In this study two distinct strategies were seen between GC and UG, with GC being more resistant to embolism formation, however it could not recover hydraulic conductance compared with UG. The inclusion of a delayed or reduced hydraulic recovery component slightly improved model predictions for GC, however not for UG, which can be related to UG being able to recover lost hydraulic conductance and therefore can maintain stomatal conductance regardless of hydraulic risk. Even though the gain-risk model shows promise in predicting plant responses, more information is needed regarding hydraulic recovery after drought.
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Affiliation(s)
- Alta Saunders
- Department of Forest and Wood Science, Stellenbosch University, Paul Sauer Building, Bosman St, Stellenbosch Central, Stellenbosch, 7599, South Africa
| | - David M Drew
- Department of Forest and Wood Science, Stellenbosch University, Paul Sauer Building, Bosman St, Stellenbosch Central, Stellenbosch, 7599, South Africa
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15
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Capelari ÉF, Dos Anjos L, Rodrigues NF, Sousa RMDJ, Silvera JAG, Margis R. Transcriptional profiling and physiological responses reveal new insights into drought tolerance in a semiarid adapted species, Anacardium occidentale. PLANT BIOLOGY (STUTTGART, GERMANY) 2021; 23:1074-1085. [PMID: 34418258 DOI: 10.1111/plb.13312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 05/05/2021] [Indexed: 06/13/2023]
Abstract
Water stress affects plant performance at various organisational levels, from morphological to molecular, with a drastic drop in crop yield. Integrative studies involving transcriptomics and physiological data in recognized tolerant species are appropriate strategies to identify and understand molecular and functional processes related to water deficit tolerance. The cashew tree (Anacardium occidentale) is a species naturally adapted to environments with low water availability associated with adverse conditions such as heat, high radiation and salinity. We used an integrative strategy, combining classical physiological measurements with high throughput RNA-seq to understand the main adaptive mechanisms of cashew to water deficit followed by recovery. Physiological analyses indicate that young cashew plants display typical isohydric behaviour. They first exhibit rapid stomatal closure, followed by CO2 assimilation, thus preserving the relative water content, membrane integrity and photosystem II activity. Differential expression was observed in 1733 genes from plant leaves exposed to water deficit stress for 26 days. Among them, 705 were upregulated and 1028 were downregulated. After rewatering, 1330 (76.7%) genes returned to their basal expression level. Transcriptional, combined with physiological data, reveal that cashew plants display high phenotypic plasticity and resilience to acute water deficit, and do not activate senescence pathways. A series of genes/pathways and processes involved with drought tolerance in cashew are evidenced, particularly in carbon metabolism, photosynthesis and chloroplast homeostasis.
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Affiliation(s)
- É F Capelari
- Programa de Pós Graduação em Genética e Biologia Molecular (PPGBM), Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - L Dos Anjos
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza, CEP, Brazil
| | - N F Rodrigues
- Programa de Pós Graduação em Genética e Biologia Molecular (PPGBM), Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - R M de J Sousa
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza, CEP, Brazil
| | - J A G Silvera
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza, CEP, Brazil
| | - R Margis
- Programa de Pós Graduação em Genética e Biologia Molecular (PPGBM), Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Centro de Biotecnologia, Laboratório de Genomas e Populações de Plantas (LGPP), Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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16
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Reproductive Stage Drought Tolerance in Wheat: Importance of Stomatal Conductance and Plant Growth Regulators. Genes (Basel) 2021; 12:genes12111742. [PMID: 34828346 PMCID: PMC8623834 DOI: 10.3390/genes12111742] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/28/2021] [Accepted: 10/28/2021] [Indexed: 12/13/2022] Open
Abstract
Drought stress requires plants to adjust their water balance to maintain tissue water levels. Isohydric plants (‘water-savers’) typically achieve this through stomatal closure, while anisohydric plants (‘water-wasters’) use osmotic adjustment and maintain stomatal conductance. Isohydry or anisohydry allows plant species to adapt to different environments. In this paper we show that both mechanisms occur in bread wheat (Triticum aestivum L.). Wheat lines with reproductive drought-tolerance delay stomatal closure and are temporarily anisohydric, before closing stomata and become isohydric at higher threshold levels of drought stress. Drought-sensitive wheat is isohydric from the start of the drought treatment. The capacity of the drought-tolerant line to maintain stomatal conductance correlates with repression of ABA synthesis in spikes and flag leaves. Gene expression profiling revealed major differences in the drought response in spikes and flag leaves of both wheat lines. While the isohydric drought-sensitive line enters a passive growth mode (arrest of photosynthesis, protein translation), the tolerant line mounts a stronger stress defence response (ROS protection, LEA proteins, cuticle synthesis). The drought response of the tolerant line is characterised by a strong response in the spike, displaying enrichment of genes involved in auxin, cytokinin and ethylene metabolism/signalling. While isohydry may offer advantages for longer term drought stress, anisohydry may be more beneficial when drought stress occurs during the critical stages of wheat spike development, ultimately improving grain yield.
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17
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Aranda I, Cadahía E, Fernández de Simón B. Specific leaf metabolic changes that underlie adjustment of osmotic potential in response to drought by four Quercus species. TREE PHYSIOLOGY 2021; 41:728-743. [PMID: 33231684 DOI: 10.1093/treephys/tpaa157] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 11/11/2020] [Indexed: 05/14/2023]
Abstract
Osmotic adjustment is almost ubiquitous as a mechanism of response to drought in many forest species. Recognized as an important mechanism of increasing turgor under water stress, the metabolic basis for osmotic adjustment has been described in only a few species. We set an experiment with four species of the genus Quercus ranked according to drought tolerance and leaf habit from evergreen to broad-leaved deciduous. A cycle of watering deprivation was imposed on seedlings, resulting in well-watered (WW) and water-stressed (WS) treatments, and their water relations were assessed from pressure-volume curves. Leaf predawn water potential (Ψpd) significantly decreased in WS seedlings, which was followed by a drop in leaf osmotic potential at full turgor (Ψπ100). The lowest values of Ψπ100 followed the ranking of decreasing drought tolerance: Quercus ilex L. < Quercus faginea Lam. < Quercus pyrenaica Willd. < Quercus petraea Matt. Liebl. The leaf osmotic potential at the turgor loss point (ΨTLP) followed the same pattern as Ψπ100 across species and treatments. The pool of carbohydrates, some organic acids and cyclitols were the main osmolytes explaining osmotic potential across species, likewise to the osmotic adjustment assessed from the decrease in leaf Ψπ100 between WW and WS seedlings. Amino acids were very responsive to WS, particularly γ-aminobutyric acid in Q. pyrenaica, but made a relatively minor contribution to osmotic potential compared with other groups of compounds. In contrast, the cyclitol proto-quercitol made a prominent contribution to the changes in osmotic potential regardless of watering treatment or species. However, different metabolites, such as quinic acid, played a more important role in osmotic adjustment in Q. ilex, distinguishing it from the other species studied. In conclusion, while osmotic adjustment was present in all four Quercus species, the molecular processes underpinning this response differed according to their phylogenetic history and specific ecology.
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Affiliation(s)
- Ismael Aranda
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Centro de Investigación Forestal, Carretera Coruña Km 7.5, E-28040 Madrid, Spain
- INAGEA, Instituto de Investigaciones Agroambientales y de Economía del Agua, 07122 Palma de Mallorca, Spain
| | - Estrella Cadahía
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Centro de Investigación Forestal, Carretera Coruña Km 7.5, E-28040 Madrid, Spain
| | - Brígida Fernández de Simón
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Centro de Investigación Forestal, Carretera Coruña Km 7.5, E-28040 Madrid, Spain
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18
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Peltier DMP, Guo J, Nguyen P, Bangs M, Gear L, Wilson M, Jefferys S, Samuels-Crow K, Yocom LL, Liu Y, Fell MK, Auty D, Schwalm C, Anderegg WRL, Koch GW, Litvak ME, Ogle K. Temporal controls on crown nonstructural carbohydrates in southwestern US tree species. TREE PHYSIOLOGY 2021; 41:388-402. [PMID: 33147630 DOI: 10.1093/treephys/tpaa149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/29/2020] [Indexed: 06/11/2023]
Abstract
In trees, large uncertainties remain in how nonstructural carbohydrates (NSCs) respond to variation in water availability in natural, intact ecosystems. Variation in NSC pools reflects temporal fluctuations in supply and demand, as well as physiological coordination across tree organs in ways that differ across species and NSC fractions (e.g., soluble sugars vs starch). Using landscape-scale crown (leaves and twigs) NSC concentration measurements in three foundation tree species (Populus tremuloides, Pinus edulis, Juniperus osteosperma), we evaluated in situ, seasonal variation in NSC responses to moisture stress on three timescales: short-term (via predawn water potential), seasonal (via leaf δ13C) and annual (via current year's ring width index). Crown NSC responses to moisture stress appeared to depend on hydraulic strategy, where J. osteosperma appears to regulate osmotic potentials (via higher sugar concentrations), P. edulis NSC responses suggest respiratory depletion and P. tremuloides responses were consistent with direct sink limitations. We also show that overly simplistic models can mask seasonal and tissue variation in NSC responses, as well as strong interactions among moisture stress at different timescales. In general, our results suggest large seasonal variation in crown NSC concentrations reflecting the multiple cofunctions of NSCs in plant tissues, including storage, growth and osmotic regulation of hydraulically vulnerable leaves. We emphasize that crown NSC pool size cannot be viewed as a simple physiological metric of stress; in situ NSC dynamics are complex, varying temporally, across species, among NSC fractions and among tissue types.
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Affiliation(s)
- Drew M P Peltier
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Jessica Guo
- Geology and Geophysics, University of Utah, Salt Lake City, UT 84112, USA
| | - Phiyen Nguyen
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Michael Bangs
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Linnea Gear
- Department of Chemistry and Biochemistry, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Michelle Wilson
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Stacy Jefferys
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Kimberly Samuels-Crow
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Larissa L Yocom
- Department of Wildland Resources and the Ecology Center, Utah State University, Logan, UT 84322, USA
| | - Yao Liu
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Michael K Fell
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - David Auty
- School of Forestry, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Christopher Schwalm
- Woods Hole Research Center, Falmouth, MA 02540, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - William R L Anderegg
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - George W Koch
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Marcy E Litvak
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Kiona Ogle
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
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19
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Yao GQ, Li FP, Nie ZF, Bi MH, Jiang H, Liu XD, Wei Y, Fang XW. Ethylene, not ABA, is closely linked to the recovery of gas exchange after drought in four Caragana species. PLANT, CELL & ENVIRONMENT 2021; 44:399-411. [PMID: 33131059 DOI: 10.1111/pce.13934] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 10/21/2020] [Indexed: 06/11/2023]
Abstract
Drought is a cyclical phenomenon in natural environments. During dehydration, stomatal closure is mainly regulated by abscisic acid (ABA) dynamics that limit transpiration in seed plants, but following rehydration, the mechanism of gas exchange recovery is still not clear. In this study, leaf water potential (ψleaf ), stomatal conductance (gs ), leaf hydraulic conductance (Kleaf ), foliar ABA level, ethylene emission rate in response to dehydration and rehydration were investigated in four Caragana species with isohydric (Caragana spinosa and C. pruinosa) and anisohydric (C. intermedia and C. microphylla) traits. Two isohydric species with ABA-induced stomatal closure exhibited more sensitive gs and Kleaf to decreasing ψleaf than two anisohydric species which exhibited a switch from ABA to water potential-driven stomatal closure during dehydration. Following rehydration, the recovery of gas exchange was not associated with a decrease in ABA level but was strongly limited by the degradation of the ethylene emission rate in all species. Furthermore, two anisohydric species with low drought-induced ethylene production exhibited more rapid recovery in gas exchange upon rehydration. Our results indicated that ethylene is a key factor regulating the drought-recovery ability in terms of gas exchange, which may shape species adaptation to drought and potential species distribution.
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Affiliation(s)
- Guang-Qian Yao
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Feng-Ping Li
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Zheng-Fei Nie
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Min-Hui Bi
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Hui Jiang
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Xu-Dong Liu
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Yang Wei
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Xiang-Wen Fang
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
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20
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Li Y, Xu Y, Chen Y, Ling L, Jiang Y, Duan H, Liu J. Effects of drought regimes on growth and physiological traits of a typical shrub species in subtropical China. Glob Ecol Conserv 2020. [DOI: 10.1016/j.gecco.2020.e01269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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21
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Lavergne A, Sandoval D, Hare VJ, Graven H, Prentice IC. Impacts of soil water stress on the acclimated stomatal limitation of photosynthesis: Insights from stable carbon isotope data. GLOBAL CHANGE BIOLOGY 2020; 26:7158-7172. [PMID: 32970907 DOI: 10.1111/gcb.15364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 09/15/2020] [Indexed: 05/08/2023]
Abstract
Atmospheric aridity and drought both influence physiological function in plant leaves, but their relative contributions to changes in the ratio of leaf internal to ambient partial pressure of CO2 (χ) - an index of adjustments in both stomatal conductance and photosynthetic rate to environmental conditions - are difficult to disentangle. Many stomatal models predicting χ include the influence of only one of these drivers. In particular, the least-cost optimality hypothesis considers the effect of atmospheric demand for water on χ but does not predict how soils with reduced water further influence χ, potentially leading to an overestimation of χ under dry conditions. Here, we use a large network of stable carbon isotope measurements in C3 woody plants to examine the acclimated response of χ to soil water stress. We estimate the ratio of cost factors for carboxylation and transpiration (β) expected from the theory to explain the variance in the data, and investigate the responses of β (and thus χ) to soil water content and suction across seed plant groups, leaf phenological types and regions. Overall, β decreases linearly with soil drying, implying that the cost of water transport along the soil-plant-atmosphere continuum increases as water available in the soil decreases. However, despite contrasting hydraulic strategies, the stomatal responses of angiosperms and gymnosperms to soil water tend to converge, consistent with the optimality theory. The prediction of β as a simple, empirical function of soil water significantly improves χ predictions by up to 6.3 ± 2.3% (mean ± SD of adjusted-R2 ) over 1980-2018 and results in a reduction of around 2% of mean χ values across the globe. Our results highlight the importance of soil water status on stomatal functions and plant water-use efficiency, and suggest the implementation of trait-based hydraulic functions into the model to account for soil water stress.
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Affiliation(s)
- Aliénor Lavergne
- Carbon Cycle Research Group, Space and Atmospheric Physics, Department of Physics, Imperial College London, London, UK
| | - David Sandoval
- Department of Life Sciences, Imperial College London, Ascot, UK
| | - Vincent J Hare
- Carbon Cycle Research Group, Space and Atmospheric Physics, Department of Physics, Imperial College London, London, UK
- Stable Light Isotope Laboratory, University of Cape Town, Cape Town, South Africa
| | - Heather Graven
- Carbon Cycle Research Group, Space and Atmospheric Physics, Department of Physics, Imperial College London, London, UK
- Grantham Institute - Climate Change and the Environment, Imperial College London, London, UK
| | - Iain Colin Prentice
- Department of Life Sciences, Imperial College London, Ascot, UK
- Grantham Institute - Climate Change and the Environment, Imperial College London, London, UK
- Department of Biological Sciences, Macquarie University, North Ryde, NSW, Australia
- Department of Earth System Science, Tsinghua University, Beijing, China
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22
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Laughlin DC, Delzon S, Clearwater MJ, Bellingham PJ, McGlone MS, Richardson SJ. Climatic limits of temperate rainforest tree species are explained by xylem embolism resistance among angiosperms but not among conifers. THE NEW PHYTOLOGIST 2020; 226:727-740. [PMID: 31981422 DOI: 10.1111/nph.16448] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 12/20/2019] [Indexed: 06/10/2023]
Abstract
Hydraulic failure explains much of the increased rates of drought-induced tree mortality around the world, underlining the importance of understanding how species distributions are shaped by their vulnerability to embolism. Here we determined which physiological traits explain species climatic limits among temperate rainforest trees in a region where chronic water limitation is uncommon. We quantified the variation in stem embolism vulnerability and leaf turgor loss point among 55 temperate rainforest tree species in New Zealand and tested which traits were most strongly related to species climatic limits. Leaf turgor loss point and stem P50 (tension at which hydraulic conductance is at 50% of maximum) were uncorrelated. Stem P50 and hydraulic safety margin were the most strongly related physiological traits to climatic limits among angiosperms, but not among conifers. Morphological traits such as wood density and leaf dry matter content did not explain species climatic limits. Stem embolism resistance and leaf turgor loss point appear to have evolved independently. Embolism resistance is the most useful predictor of the climatic limits of angiosperm trees. High embolism resistance in the curiously overbuilt New Zealand conifers suggests that their xylem properties may be more closely related to growing slowly under nutrient limitation and to resistance to microbial decomposition.
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Affiliation(s)
- Daniel C Laughlin
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - Sylvain Delzon
- INRA, BIOGECO, University of Bordeaux, 33615, Pessac, France
| | | | - Peter J Bellingham
- Manaaki Whenua - Landcare Research, PO Box 69040, Lincoln, 7640, New Zealand
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Matthew S McGlone
- Manaaki Whenua - Landcare Research, PO Box 69040, Lincoln, 7640, New Zealand
| | - Sarah J Richardson
- Manaaki Whenua - Landcare Research, PO Box 69040, Lincoln, 7640, New Zealand
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Williams GM, Ginzel MD. Spatial and Climatic Factors Influence Ambrosia Beetle (Coleoptera: Curculionidae) Abundance in Intensively Managed Plantations of Eastern Black Walnut. ENVIRONMENTAL ENTOMOLOGY 2020; 49:49-58. [PMID: 31746336 DOI: 10.1093/ee/nvz125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Indexed: 06/10/2023]
Abstract
Invasive ambrosia beetles are among the most economically important pests of forest and plantation trees world-wide. The development of effective management guidelines for these pests in plantations of high-value hardwood species is hindered by a lack of baseline information regarding their seasonal abundance and dispersal behavior. By analyzing long-term monitoring data from intensively-managed plantations of eastern black walnut (Juglans nigra L.) in north-central Indiana, we identified key spatial and climatic variables that could improve the timing and precision of management actions to reduce ambrosia beetle populations. We also used geospatial analyses to compare species-specific spatial patterns of population density and evaluate the sensitivity of the trap density deployed in our long-term monitoring efforts. Xyleborinus saxesenii Ratzeburg and Xylosandrus crassiusculus Matschulsky (Coleoptera: Curculionidae) were more abundant during the spring in years preceded by a hot, dry growing season, and cold winter. Both species were positively associated with plantation edges during the fall flight period. However, X. saxesenii was less abundant in plantations close to forest corridors, whereas X. crassiusculus was more abundant in plantations closer to woodlots and other walnut plantations. Geospatial analysis revealed X. crassiusculus is active in larger, more spatially continuous patches than X. saxesenii, and that 200-m trap spacing is likely to be sufficient to detect both species in the spring flight period but may be insufficient to detect X. saxesenii during the fall flight period. Our findings underscore the power and utility of long-term monitoring to improve management strategies.
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Affiliation(s)
- G M Williams
- Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN
| | - M D Ginzel
- Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN
- Department of Entomology, Purdue University, West Lafayette, IN
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24
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Tarin T, Nolan RH, Medlyn BE, Cleverly J, Eamus D. Water-use efficiency in a semi-arid woodland with high rainfall variability. GLOBAL CHANGE BIOLOGY 2020; 26:496-508. [PMID: 31597216 DOI: 10.1111/gcb.14866] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 08/30/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
As the ratio of carbon uptake to water use by vegetation, water-use efficiency (WUE) is a key ecosystem property linking global carbon and water cycles. It can be estimated in several ways, but it is currently unclear how different measures of WUE relate, and how well they each capture variation in WUE with soil moisture availability. We evaluated WUE in an Acacia-dominated woodland ecosystem of central Australia at various spatial and temporal scales using stable carbon isotope analysis, leaf gas exchange and eddy covariance (EC) fluxes. Semi-arid Australia has a highly variable rainfall pattern, making it an ideal system to study how WUE varies with water availability. We normalized our measures of WUE across a range of vapour pressure deficits using g1 , which is a parameter derived from an optimal stomatal conductance model and which is inversely related to WUE. Continuous measures of whole-ecosystem g1 obtained from EC data were elevated in the 3 days following rain, indicating a strong effect of soil evaporation. Once these values were removed, a close relationship of g1 with soil moisture content was observed. Leaf-scale values of g1 derived from gas exchange were in close agreement with ecosystem-scale values. In contrast, values of g1 obtained from stable isotopes did not vary with soil moisture availability, potentially indicating remobilization of stored carbon during dry periods. Our comprehensive comparison of alternative measures of WUE shows the importance of stomatal control of fluxes in this highly variable rainfall climate and demonstrates the ability of these different measures to quantify this effect. Our study provides the empirical evidence required to better predict the dynamic carbon-water relations in semi-arid Australian ecosystems.
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Affiliation(s)
- Tonantzin Tarin
- Terrestrial Ecohydrology Research Group, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
- Department of Soil and Plant Sciences, University of Delaware, Newark, DE, USA
| | - Rachael H Nolan
- Terrestrial Ecohydrology Research Group, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Belinda E Medlyn
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - James Cleverly
- Terrestrial Ecohydrology Research Group, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
- Terrestrial Ecosystem Research Network (TERN), University of Technology, Sydney, NSW, Australia
| | - Derek Eamus
- Terrestrial Ecohydrology Research Group, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
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25
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Guo JS, Hultine KR, Koch GW, Kropp H, Ogle K. Temporal shifts in iso/anisohydry revealed from daily observations of plant water potential in a dominant desert shrub. THE NEW PHYTOLOGIST 2020; 225:713-726. [PMID: 31519032 DOI: 10.1111/nph.16196] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 09/06/2019] [Indexed: 05/25/2023]
Abstract
Plant species are characterized along a spectrum of isohydry to anisohydry depending on their regulation of water potential (Ψ), but the plasticity of hydraulic strategies is largely unknown. The role of environmental drivers was evaluated in the hydraulic behavior of Larrea tridentata, a drought-tolerant desert shrub that withstands a wide range of environmental conditions. With a 1.5 yr time-series of 2324 in situ measurements of daily predawn and midday Ψ, the temporal variability of hydraulic behavior was explored in relation to soil water supply, atmospheric demand and temperature. Hydraulic behavior in Larrea was highly dynamic, ranging from partial isohydry to extreme anisohydry. Larrea exhibited extreme anisohydry under wet soil conditions corresponding to periods of high productivity, whereas partial isohydry was exhibited after prolonged dry or cold conditions, when productivity was low. Environmental conditions can strongly influence plant hydraulic behavior at relatively fast timescales, which enhances our understanding of plant drought responses. Although species may exhibit a dominant hydraulic behavior, variable environmental conditions can prompt plasticity in Ψ regulation, particularly for species in seasonally dry climates.
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Affiliation(s)
- Jessica S Guo
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Kevin R Hultine
- Department of Research, Conservation, and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
| | - George W Koch
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Heather Kropp
- Department of Geography, Colgate University, Hamilton, NY, 13346, USA
| | - Kiona Ogle
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, 86011, USA
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26
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Gori A, Tattini M, Centritto M, Ferrini F, Marino G, Mori J, Guidi L, Brunetti C. Seasonal and daily variations in primary and secondary metabolism of three maquis shrubs unveil different adaptive responses to Mediterranean climate. CONSERVATION PHYSIOLOGY 2019; 7:coz070. [PMID: 32467757 PMCID: PMC7245392 DOI: 10.1093/conphys/coz070] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 08/08/2019] [Accepted: 08/29/2019] [Indexed: 05/20/2023]
Abstract
Maquis species play a central role in the maintenance of coastal ecosystems thanks to anatomical, physiological and biochemical features evolved to cope with severe stress conditions. Because the seasonal and daily dynamics of physiological and biochemical traits of maquis species are not fully addressed, we performed a field study on three coexisting Mediterranean shrubs (Pistacia lentiscus L. and Phillyrea latifolia L., evergreen schlerophylls, and Cistus incanus L., semi-deciduous) aiming at detecting the main adaptive differences, on a seasonal and daily basis, in primary and secondary metabolism along with the principal climatic determinants. These species differed in their physiological and biochemical responses especially on a seasonal level. In P. latifolia, a great investment in antioxidant phenylpropanoids contributed to maintain high photosynthetic rates throughout the whole growing season. In C. incanus, high carotenoid content associated with chlorophyll (Chl) regulation alleviated oxidative damage during the hot and dry summers and help recover photosynthesis in autumn. In P. lentiscus, high abscisic acid levels allowed a strict control of stomata, while fine Chla/Chlb regulation concurred to avoid photoinhibition in summer. Temperature resulted the most important climatic factor controlling the physiological and biochemical status of these coexisting shrubs and, thus, in determining plant performances in this Mediterranean coastal habitat.
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Affiliation(s)
- Antonella Gori
- Department of Agriculture, Food, Environment and Forestry, University of Florence, viale delle Idee 30, 50019, Sesto Fiorentino, Florence, Italy
| | - Massimiliano Tattini
- Institute for Sustainable Plant Protection, National Research Council of Italy, via Madonna del Piano 10, 50019, Sesto Fiorentino, Florence, Italy
| | - Mauro Centritto
- Institute for Sustainable Plant Protection, National Research Council of Italy, via Madonna del Piano 10, 50019, Sesto Fiorentino, Florence, Italy
| | - Francesco Ferrini
- Department of Agriculture, Food, Environment and Forestry, University of Florence, viale delle Idee 30, 50019, Sesto Fiorentino, Florence, Italy
| | - Giovanni Marino
- Institute for Sustainable Plant Protection, National Research Council of Italy, via Madonna del Piano 10, 50019, Sesto Fiorentino, Florence, Italy
| | - Jacopo Mori
- Department of Agriculture, Food, Environment and Forestry, University of Florence, viale delle Idee 30, 50019, Sesto Fiorentino, Florence, Italy
| | - Lucia Guidi
- Department of Agriculture, Food and Environment, University of Pisa, Lungarno Pacinotti 43, 56126, Pisa, Italy
| | - Cecilia Brunetti
- Institute for Sustainable Plant Protection, National Research Council of Italy, via Madonna del Piano 10, 50019, Sesto Fiorentino, Florence, Italy
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27
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Yang L, Zhao Y, Zhang Q, Cheng L, Han M, Ren Y, Yang L. Effects of drought-re-watering-drought on the photosynthesis physiology and secondary metabolite production of Bupleurum chinense DC. PLANT CELL REPORTS 2019; 38:1181-1197. [PMID: 31165250 DOI: 10.1007/s00299-019-02436-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 05/29/2019] [Indexed: 06/09/2023]
Abstract
Drastic changes in soil water content can activate the short-term high expression of key enzyme-encoding genes involved in secondary metabolite synthesis thereby increasing the content of secondary metabolites. Bupleurum chinense DC. is a traditional medicinal herb that is famous for its abundant saikosaponins. In the current study, the effects of drought-re-watering-drought on the photosynthesis physiology and biosynthesis of saikosaponins were investigated in 1-year-old B. chinense. The results showed that alterations in soil moisture altered the photosynthesis physiological process of B. chinense. The dry weight and fresh weight of the roots, photosynthesis capacity, chlorophyll fluorescence parameters, and SOD, POD and CAT activities were significantly reduced, and the contents of SP, soluble sugars, PRO and MDA increased. There were strong correlations between different physiological stress indices. All indices promoted and restricted each other, responded to soil moisture changes synergistically, maintained plant homeostasis and guaranteed normal biological activities. It was found that RW and RD_1 were the key stages of the water-control experiment affecting the expression of saikosaponin-related genes. At these two stages, the expression of multiple genes was affected by changes in soil moisture, with their expression levels reaching several-fold higher than those at the previous stage. We noticed that the expression of saikosaponin synthesis genes (which were rapidly upregulated at the RW and RD_1 stages) did not coincide with the rapid accumulation of saikosaponins (at the RD-2 stage), which were found to correspond to each other at the later stages of the water-control experiment. This finding indicates that there is a time lag between gene expression and the final product synthesis. Rapid changes in the external environment (RW to RD_1) have a short-term promoting effect on gene expression. This study reveals that short-term stress regulation may be an effective way to improve the quality of medicinal materials.
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Affiliation(s)
- Linlin Yang
- Cultivation Base of State Key Laboratory for Ecological Restoration and Ecosystem Management of Jilin Province, Ministry of Science and Technology, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, People's Republic of China
| | - Yu Zhao
- Cultivation Base of State Key Laboratory for Ecological Restoration and Ecosystem Management of Jilin Province, Ministry of Science and Technology, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, People's Republic of China
| | - Qi Zhang
- Cultivation Base of State Key Laboratory for Ecological Restoration and Ecosystem Management of Jilin Province, Ministry of Science and Technology, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, People's Republic of China
| | - Lin Cheng
- Cultivation Base of State Key Laboratory for Ecological Restoration and Ecosystem Management of Jilin Province, Ministry of Science and Technology, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, People's Republic of China
| | - Mei Han
- Cultivation Base of State Key Laboratory for Ecological Restoration and Ecosystem Management of Jilin Province, Ministry of Science and Technology, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, People's Republic of China
| | - Yueying Ren
- Cultivation Base of State Key Laboratory for Ecological Restoration and Ecosystem Management of Jilin Province, Ministry of Science and Technology, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, People's Republic of China.
| | - Limin Yang
- Cultivation Base of State Key Laboratory for Ecological Restoration and Ecosystem Management of Jilin Province, Ministry of Science and Technology, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, People's Republic of China.
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28
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Henry C, John GP, Pan R, Bartlett MK, Fletcher LR, Scoffoni C, Sack L. A stomatal safety-efficiency trade-off constrains responses to leaf dehydration. Nat Commun 2019; 10:3398. [PMID: 31363097 PMCID: PMC6667445 DOI: 10.1038/s41467-019-11006-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 06/10/2019] [Indexed: 01/08/2023] Open
Abstract
Stomata, the microvalves on leaf surfaces, exert major influences across scales, from plant growth and productivity to global carbon and water cycling. Stomatal opening enables leaf photosynthesis, and plant growth and water use, whereas plant survival of drought depends on stomatal closure. Here we report that stomatal function is constrained by a safety-efficiency trade-off, such that species with greater stomatal conductance under high water availability (gmax) show greater sensitivity to closure during leaf dehydration, i.e., a higher leaf water potential at which stomatal conductance is reduced by 50% (Ψgs50). The gmax - Ψgs50 trade-off and its mechanistic basis is supported by experiments on leaves of California woody species, and in analyses of previous studies of the responses of diverse flowering plant species around the world. Linking the two fundamental key roles of stomata-the enabling of gas exchange, and the first defense against drought-this trade-off constrains the rates of water use and the drought sensitivity of leaves, with potential impacts on ecosystems.
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Affiliation(s)
- Christian Henry
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
| | - Grace P John
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Integrative Biology, University of Texas at Austin, 2415 Speedway, Austin, TX, 78712, USA
| | - Ruihua Pan
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- School of Ecology and Environment, Inner Mongolia University, 235 University West Road, 010021, Hohhot, Inner Mongolia, China
| | - Megan K Bartlett
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Viticulture and Enology, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA
| | - Leila R Fletcher
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
| | - Christine Scoffoni
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Biological Sciences, California State University, Los Angeles, 5151 State University Drive, Los Angeles, CA, 90032, USA
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA.
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29
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Fu X, Meinzer FC, Woodruff DR, Liu YY, Smith DD, McCulloh KA, Howard AR. Coordination and trade-offs between leaf and stem hydraulic traits and stomatal regulation along a spectrum of isohydry to anisohydry. PLANT, CELL & ENVIRONMENT 2019; 42:2245-2258. [PMID: 30820970 DOI: 10.1111/pce.13543] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 02/22/2019] [Accepted: 02/24/2019] [Indexed: 06/09/2023]
Abstract
The degree of plant iso/anisohydry, a widely used framework for classifying species-specific hydraulic strategies, integrates multiple components of the whole-plant hydraulic pathway. However, little is known about how it associates with coordination of functional and structural traits within and across different organs. We examined stem and leaf hydraulic capacitance and conductivity/conductance, stem xylem anatomical features, stomatal regulation of daily minimum leaf and stem water potential (Ψ), and the kinetics of stomatal responses to vapour pressure deficit (VPD) in six diverse woody species differing markedly in their degree of iso/anisohydry. At the stem level, more anisohydric species had higher wood density and lower native capacitance and conductivity. Like stems, leaves of more anisohydric species had lower hydraulic conductance; however, unlike stems, their leaves had higher native capacitance at their daily minimum values of leaf Ψ. Moreover, rates of VPD-induced stomatal closure were related to intrinsic rather than native leaf capacitance and were not associated with species' degree of iso/anisohydry. Our results suggest a trade-off between hydraulic storage and efficiency in the leaf, but a coordination between hydraulic storage and efficiency in the stem along a spectrum of plant iso/anisohydry.
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Affiliation(s)
- Xiaoli Fu
- Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- Zhongke-Ji'an Institute for Eco-Environmental Sciences, Ji'an, China
| | | | - David R Woodruff
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, Oregon
| | - Yan-Yan Liu
- Key Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education, Guangxi Teachers Education University, Nanning, China
| | - Duncan D Smith
- Department of Botany, University of Wisconsin, Madison, Wisconsin
| | | | - Ava R Howard
- Department of Biology, Western Oregon University, Monmouth, Oregon
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30
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Leaf Gas Exchange, Plant Water Relations and Water Use Efficiency of Vigna Unguiculata L. Walp. Inoculated with Rhizobia under Different Soil Water Regimes. WATER 2019. [DOI: 10.3390/w11030498] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Impact of soil water regimes on physiological responses and water use efficiency (WUE) for Vigna unguiculata L. Walp. (cowpea) inoculated with rhizobia still remains implicit. Therefore, the goal of the current study was to examine the leaf gas exchange, abscisic acid (ABA) and hydraulic signaling, WUE and carbon and oxygen isotopic compositions (δ13C and δ18O) of cowpea under different soil water levels. The treatments included soil water regimes at three levels (90%, 70%, and 50% of soil water holding capacity (SWHC)) and two inoculation forms (inoculated and non-inoculated with rhizobia). The results showed that across the inoculation treatments, reduced soil water regimes depressed both stomatal conductance (gs) and photosynthesis (An) of the leaves, nonetheless, the decrease of gs was more pronounced compared with the reduction in An. Consequently, the intrinsic water use efficiency (WUEi) was improved in the treatments under decreased soil water conditions. Plant WUE was also improved when soil water contents decreased as exemplified by the increased leaf δ13C and δ18O, indicating the enhanced plant WUE was mainly attributed to the decrease of gs. Significant interactions between soil water regimes and rhizobia treatments for root water potential (RWP), leaf water potential (LWP), and gs were found due to the different responses of rhizobia to varied soil water regimes. Inoculation could improve plant water status and gs under 70% and 90% SWHC compared to 50% SWHC with negative effect from rhizobia. A moderate soil water regime is suggested for cowpea production in terms of high WUE with a minor biomass reduction.
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31
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Levin AD, Williams LE, Matthews MA. A continuum of stomatal responses to water deficits among 17 wine grape cultivars (Vitis vinifera). FUNCTIONAL PLANT BIOLOGY : FPB 2019; 47:11-25. [PMID: 31615618 DOI: 10.1071/fp19073] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 07/19/2019] [Indexed: 06/10/2023]
Abstract
Vitis vinifera L. cultivars have been previously classified as isohydric, near-isohydric, anisohydric or isohydrodynamic, depending on the study. To test the hypothesis that V. vinifera cultivars' stomatal behaviour can be separated into distinct classes, 17 cultivars grown in a replicated field trial were subjected to three irrigation treatments to manipulate vine water status across multiple years. Predawn (ΨPD) and midday (Ψl) leaf water potential and midday stomatal conductance (gs) were measured regularly throughout several seasons. The relationship of gs to Ψl was best modelled as a sigmoidal function and maximum stomatal conductance (gmax), water status at the onset of stomatal closure (Ψl95), sensitivity of closure (gsensitivity) and water status at the end of closure (Ψl25) were compared. There were no significant differences in gmax among cultivars. Cultivar-specific responses of gs to Ψl were broadly distributed along a continuum based on the relationship between Ψl95 and gsensitivity. Season-long cultivar mean Ψl values were positively related to Ψl25. In general, cultivars responded similarly to one another at high and low water status, but their stomatal behaviour differed at moderate water deficits. The results show that V. vinifera cultivars possess both iso- and anisohydric stomatal behaviours that depend on the intensity of water deficits, and call into question previous classifications assuming a single behaviour.
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Affiliation(s)
- Alexander D Levin
- Department of Horticulture, Oregon State University, Corvallis, OR 97331, USA; and Southern Oregon Research and Extension Center, 569 Hanley Road., Central Point, OR 97502, USA; and Corresponding author.
| | - Larry E Williams
- Department of Viticulture and Enology, University of California, Davis, CA 95616, USA; and Kearney Agricultural Research and Extension Center, 9240 S. Riverbend Avenue., Parlier, CA 93648, USA
| | - Mark A Matthews
- Department of Viticulture and Enology, University of California, Davis, CA 95616, USA
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32
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Brunetti C, Loreto F, Ferrini F, Gori A, Guidi L, Remorini D, Centritto M, Fini A, Tattini M. Metabolic plasticity in the hygrophyte Moringa oleifera exposed to water stress. TREE PHYSIOLOGY 2018; 38:1640-1654. [PMID: 30137639 DOI: 10.1093/treephys/tpy089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 07/24/2018] [Indexed: 05/19/2023]
Abstract
Over the past decades, introduction of many fast-growing hygrophilic, and economically valuable plants into xeric environments has occurred. However, production and even survival of these species may be threatened by harsh climatic conditions unless an effective physiological and metabolic plasticity is available. Moringa oleifera Lam., a multipurpose tree originating from humid sub-tropical regions of India, is widely cultivated in many arid countries because of its multiple uses. We tested whether M. oleifera can adjust primary and secondary metabolism to efficiently cope with increasing water stress. It is shown that M. oleifera possesses an effective isohydric behavior. Water stress induced a quick and strong stomatal closure, driven by abscisic acid (ABA) accumulation, and leading to photosynthesis inhibition with consequent negative effects on biomass production. However, photochemistry was not impaired and maximal fluorescence and saturating photosynthesis remained unaffected in stressed leaves. We report for the first time that M. oleifera produces isoprene, and show that isoprene emission increased three-fold during stress progression. It is proposed that higher isoprene biosynthesis helps leaves cope with water stress through its antioxidant or membrane stabilizing action, and also indicates a general MEP (methylerythritol 4-phosphate) pathway activation that further helps protect photosynthesis under water stress. Increased concentrations of antioxidant flavonoids were also observed in water stressed leaves, and probably cooperate in limiting irreversible effects of the stress in M. oleifera leaves. The observed metabolic and phenotypic plasticity may facilitate the establishment of M. oleifera in xeric environments, sustaining the economic and environmental value of this plant.
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Affiliation(s)
- Cecilia Brunetti
- National Research Council of Italy, Department of Biology, Agriculture and Food Sciences, Trees and Timber Institute, Sesto Fiorentino (Florence), Italy
- Department of Agri-Food Production and Environmental Sciences, University of Florence, Sesto Fiorentino (Florence), Italy
| | - Francesco Loreto
- National Research Council of Italy, Department of Biology, Agriculture and Food Sciences, Piazzale Aldo Moro 7, Roma, Italy
| | - Francesco Ferrini
- Department of Agri-Food Production and Environmental Sciences, University of Florence, Sesto Fiorentino (Florence), Italy
| | - Antonella Gori
- Department of Agri-Food Production and Environmental Sciences, University of Florence, Sesto Fiorentino (Florence), Italy
| | - Lucia Guidi
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Damiano Remorini
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Mauro Centritto
- National Research Council of Italy, Department of Biology, Agriculture and Food Sciences, Trees and Timber Institute, Sesto Fiorentino (Florence), Italy
| | - Alessio Fini
- Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, Milan, Italy
| | - Massimiliano Tattini
- National Research Council of Italy, Department of Biology, Agriculture and Food Sciences, Institute for Sustainable Plant Protection, Sesto Fiorentino (Florence), Italy
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33
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Martins GS, Freitas NC, Máximo WPF, Paiva LV. Gene expression in two contrasting hybrid clones of Eucalyptus camaldulensis x Eucalyptus urophylla grown under water deficit conditions. JOURNAL OF PLANT PHYSIOLOGY 2018; 229:122-131. [PMID: 30071503 DOI: 10.1016/j.jplph.2018.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 07/21/2018] [Accepted: 07/25/2018] [Indexed: 06/08/2023]
Abstract
The physiological and molecular responses to water stress are mediated by a range of mechanisms, many of which involve abscisic acid (ABA)-dependent signaling pathways. In addition, plants contain drought response genes that can be induced by ABA-independent routes, mediated by secondary messengers such as Ca2+, or regulated by epigenetic modifications. The complex processes involved in the response to water stress can be investigated using molecular techniques to evaluate the expression patterns of genes of interest and to infer the behavior of different genotypes and species. In the present study, we first analyzed the stability of a set of reference genes for normalization of the gene expression with real-time quantitative polymerase chain reaction (RT-qPCR), since there were no results related to the genotype used in this study. We verified that although there were some variations between algorithms used, the three most stable reference genes were SAND, PP2A-3 and EF-1α. The expressions of genes encoding for proteins associated with drought-tolerance responses, namely 9-cis-epoxycarotenoid dioxygenase 3 (EgrNCED3), pyrabactin resistance 1 (EgrPYR1), dehydration-responsive element-binding 2.5 (EgrDREB2.5) transcription factors, calcium-dependent protein kinase 26 (EgrCDPK26), methyl transferase 1 (EgrMET1) and deficient in DNA methylation 1 (EgrDDM1) protein, were determined by RT-qPCR in leaf samples from drought sensitive (VM05) and drought tolerant (VM01) clones of the hybrid Eucalyptus camaldulensis x Eucalyptus urophylla grown under water stress and irrigation conditions. When the two clones were maintained under conditions of water deficiency, VM01 exhibited higher expression levels of EgrNCED3 and EgrPYR1 genes than VM05 at all sampling times, implying that ABA biosynthesis and subsequent induction of the ABA-dependent cascade mediated by the PYR1-ABA receptor complex were enhanced in the tolerant clone. Under water-stress conditions, this clone also presented increased expression of the EgrDREB2.5 gene, representative of an ABA-independent cascade, and of the EgrCPK26 gene, related to stomatal opening and closure. On the other hand, the expression levels of EgrMET1 and EgrDDM1 genes in the sensitive clone were higher than in the tolerant clone under all conditions, showing a putative impact of epigenetic modifications on tolerance to water deficiency. The results obtained indicate that the superior ability of the VM01-tolerant clone to perceive water deficiency and activate drought-resistance genes is associated with the high expression levels of EgrNCED3, EgrPYR1 and EgrDREB2.5 under water-stress conditions. These findings will facilitate future research on the functional characterization of stress-related response genes, the identification of molecular markers, the evaluation of drought tolerance and genetic transformation in tree species.
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Affiliation(s)
- Guilherme Silva Martins
- Laboratório Central de Biologia Molecular, Departamento de Química, Universidade Federal de Lavras, 37200-000, Lavras, MG, Brazil.
| | - Natália Chagas Freitas
- Laboratório Central de Biologia Molecular, Departamento de Química, Universidade Federal de Lavras, 37200-000, Lavras, MG, Brazil.
| | - Wesley Pires Flausino Máximo
- Laboratório Central de Biologia Molecular, Departamento de Química, Universidade Federal de Lavras, 37200-000, Lavras, MG, Brazil.
| | - Luciano Vilela Paiva
- Laboratório Central de Biologia Molecular, Departamento de Química, Universidade Federal de Lavras, 37200-000, Lavras, MG, Brazil.
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Nolan RH, Sinclair J, Eldridge DJ, Ramp D. Biophysical risks to carbon sequestration and storage in Australian drylands. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 208:102-111. [PMID: 29248786 DOI: 10.1016/j.jenvman.2017.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 11/29/2017] [Accepted: 12/02/2017] [Indexed: 06/07/2023]
Abstract
Carbon abatement schemes that reduce land clearing and promote revegetation are now an important component of climate change policy globally. There is considerable potential for these schemes to operate in drylands which are spatially extensive. However, projects in these environments risk failure through unplanned release of stored carbon to the atmosphere. In this review, we identify factors that may adversely affect the success of vegetation-based carbon abatement projects in dryland ecosystems, evaluate their likelihood of occurrence, and estimate the potential consequences for carbon storage and sequestration. We also evaluate management strategies to reduce risks posed to these carbon abatement projects. Identified risks were primarily disturbances, including unplanned fire, drought, and grazing. Revegetation projects also risk recruitment failure, thereby failing to reach projected rates of sequestration. Many of these risks are dependent on rainfall, which is highly variable in drylands and susceptible to further variation under climate change. Resprouting vegetation is likely to be less vulnerable to disturbance and have faster recovery rates upon release from disturbance. We conclude that there is a strong impetus for identifying management strategies and risk reduction mechanisms for carbon abatement projects. Risk mitigation would be enhanced by effective co-ordination of mitigation strategies at scales larger than individual abatement project boundaries, and by implementing risk assessment throughout project planning and implementation stages. Reduction of risk is vital for maximising carbon sequestration of individual projects and for reducing barriers to the establishment of new projects entering the market.
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Affiliation(s)
- Rachael H Nolan
- Centre for Compassionate Conservation, University of Technology Sydney, PO Box 123, Broadway, NSW 2007, Australia.
| | - Jennifer Sinclair
- Centre for Compassionate Conservation, University of Technology Sydney, PO Box 123, Broadway, NSW 2007, Australia; GreenCollar, The Rocks, Sydney, NSW 2000, Australia
| | - David J Eldridge
- School of Biological, Earth and Environmental Sciences, University of New South Wales, NSW 2052, Australia
| | - Daniel Ramp
- Centre for Compassionate Conservation, University of Technology Sydney, PO Box 123, Broadway, NSW 2007, Australia
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Johnson DM, Berry ZC, Baker KV, Smith DD, McCulloh KA, Domec J. Leaf hydraulic parameters are more plastic in species that experience a wider range of leaf water potentials. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13049] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Z. Carter Berry
- Department of Natural Resources and the Environment University of New Hampshire Durham NH USA
| | | | - Duncan D. Smith
- Department of Botany University of Wisconsin‐Madison Madison WI USA
| | | | - Jean‐Christophe Domec
- Bordeaux Sciences Agro UMR INRA‐ISPA 1391 Gradignan France
- Nicholas School of the Environment Duke University Durham NC USA
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