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Harrison Day BL, Brodersen CR, Brodribb TJ. Weak link or strong foundation? Vulnerability of fine root networks and stems to xylem embolism. THE NEW PHYTOLOGIST 2024. [PMID: 39267263 DOI: 10.1111/nph.20115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Accepted: 08/21/2024] [Indexed: 09/17/2024]
Abstract
Resolving the position of roots in the whole-plant hierarchy of drought-induced xylem embolism resistance is fundamental for predicting when species become isolated from soil water resources. Published research generally suggests that roots are the most vulnerable organ of the plant vascular system, although estimates vary significantly. However, our knowledge of root embolism excludes the fine roots (< 2 mm diameter) that form the bulk of total absorptive surface area of the root network for water and nutrient uptake. We measured fine root and stem xylem vulnerability in 10 vascular plant species from the major land plant clades (five angiosperms, three conifers, a fern and lycophyte), using standardised in situ methods (Optical Methods and MicroCT). Mean fine root embolism resistance across the network matched or exceeded stems in all study species. In six of these species (one fern, one lycophyte, three conifers and one angiosperm), fine roots were significantly more embolism resistant than stems. No clear relationship was found between root xylem conduit diameter and vulnerability. These results provide insight into the resistance of the plant hydraulic pathway at the site of water and nutrient uptake, and challenge the long-standing assumption that fine roots are more vulnerable than stems.
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Affiliation(s)
- Beatrice L Harrison Day
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS, 7001, Australia
- School of the Environment, Yale University, New Haven, CT, 06520, USA
| | - Craig R Brodersen
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS, 7001, Australia
- School of the Environment, Yale University, New Haven, CT, 06520, USA
| | - Timothy J Brodribb
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS, 7001, Australia
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Huang X, Hou ZL, Ma BL, Zhao H, Jiang ZM, Cai J. Seasonality in embolism resistance and hydraulic capacitance jointly mediate hydraulic safety in branches and leaves of oriental cork oak (Quercus variabilis Bl.). TREE PHYSIOLOGY 2024; 44:tpae109. [PMID: 39216110 DOI: 10.1093/treephys/tpae109] [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: 11/08/2023] [Revised: 05/31/2024] [Accepted: 08/29/2024] [Indexed: 09/04/2024]
Abstract
Seasonality in temperate regions is prominent during the era of increased climatic variability. A hydraulic trait that can adjust to seasonally changing climatic conditions is crucial for tree safety. However, little attention has been paid to the intraspecific seasonality of drought-related traits and hydraulic safety of keystone forest trees. We examined seasonal variations in the key morphological and physiological traits as well as multiple hydraulic safety margins (SMs) at the branch and leaf levels in oriental cork oak (Quercus variabilis Bl.), which is predominant in Chinese temperate forests. Pneumatic measurements indicated that, as seasons progressed, the water potential at which 50% of branch embolisms occur (P50_branch) decreased from -3.34 to -4.23 MPa, with a coefficient of variation (CV) of 9.08%. Sapwood capacitance ranged from 48.19 to 248.08 kg m-3 MPa-1, peaking in autumn and reaching minimum in winter (CV 60.58%). Rehydration kinetics confirmed higher leaf embolism vulnerability (P50_leaf) in spring and autumn than those in summer, with values ranging from -1.06 to -3.02 MPa (CV 39.85%). All leaf pressure-volume (PV) traits shifted with growth, with CVs ranging from 6.95% to 46.69%. Sapwood density had significant negative correlations with P50_branch and hydraulic capacitance for elastic water storage, whereas leaf mass per area was linearly associated with PV traits but not with P50_leaf. Furthermore, the branch typical SMs (difference between branch midday water potential and P50_branch) were consistently >1.84 MPa, and vulnerability segmentation was prevalent throughout, implying a plausible hydraulic foundation for the dominance of Q. variabilis. Diverse hydraulic response patterns existed across seasons, leading to positive SMs mediated by the aforementioned physiological traits. Although Q. variabilis exhibits a high level of hydraulic safety, its susceptibility to sudden summer droughts may increase due to global climate change.
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Affiliation(s)
- Xin Huang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Zhuo-Liang Hou
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Bo-Long Ma
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Han Zhao
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Zai-Min Jiang
- College of Life, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
- Qinling National Forest Ecosystem Research Station, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Jing Cai
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
- Qinling National Forest Ecosystem Research Station, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
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3
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Silva LM, Pereira L, Kaack L, Guan X, Pfaff J, Trabi CL, Jansen S. The potential link between gas diffusion and embolism spread in angiosperm xylem: Evidence from flow-centrifuge experiments and modelling. PLANT, CELL & ENVIRONMENT 2024. [PMID: 39119783 DOI: 10.1111/pce.15084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 06/19/2024] [Accepted: 07/27/2024] [Indexed: 08/10/2024]
Abstract
Understanding xylem embolism formation is challenging due to dynamic changes and multiphase interactions in conduits. Here, we hypothesise that embolism spread involves gas diffusion in xylem, and is affected by time. We measured hydraulic conductivity (Kh) in flow-centrifuge experiments over 1 h at a given pressure and temperature for stem samples of three angiosperm species. Temporal changes in Kh at 5, 22, and 35°C, and at various pressures were compared to modelled gas concentration changes in a recently embolised vessel in the centre of a centrifuge sample. Temporal changes in Kh were logarithmic and species-specific. Maximum relative increases of Kh between 6% and 40% happened at 22°C for low centrifugal speed (<3250 RPM), while maximum decreases between 41% and 61% occurred at higher speeds. These reductions in Kh were experimentally shown to be associated with a temporal increase of embolism at the centre of centrifuge samples, which was likely associated with gas concentration increases in recently embolized vessels. Although embolism is mostly pressure-driven, our experimental and modelled data indicate that time, conduit characteristics, and temperature are involved due to their potential role in gas diffusion. Gas diffusion, however, does not seem to cover the entire process of embolism spread.
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Affiliation(s)
| | | | - Lucian Kaack
- Institute of Botany, Ulm University, Ulm, Germany
- Botanical Garden of Ulm University, Hans-Krebs-Weg, Ulm, Germany
| | - Xinyi Guan
- Institute of Botany, Ulm University, Ulm, Germany
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, China
| | - Jonas Pfaff
- Institute of Botany, Ulm University, Ulm, Germany
| | - Christophe L Trabi
- Institute of Botany, Ulm University, Ulm, Germany
- Core Facility Confocal and Multiphoton Microscopy, Ulm University, Ulm, Germany
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4
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Moreno M, Limousin JM, Simioni G, Badel E, Rodríguez-Calcerrada J, Cochard H, Torres-Ruiz JM, Dupuy JL, Ruffault J, Ormeno E, Delzon S, Fernandez C, Ourcival JM, Martin-StPaul N. Hydraulic plasticity and water use regulation act to maintain the hydraulic safety margins of Mediterranean trees in rainfall exclusion experiments. PLANT, CELL & ENVIRONMENT 2024. [PMID: 39077899 DOI: 10.1111/pce.15066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 06/14/2024] [Accepted: 07/17/2024] [Indexed: 07/31/2024]
Abstract
Hydraulic failure due to xylem embolism has been identified as one of the main mechanisms involved in drought-induced forest decline. Trees vulnerability to hydraulic failure depends on their hydraulic safety margin (HSM). While it has been shown that HSM globally converges between tree species and biomes, there is still limited knowledge regarding how HSM can adjust locally to varying drought conditions within species. In this study, we relied on three long-term partial rainfall exclusion experiments to investigate the plasticity of hydraulic traits and HSM for three Mediterranean tree species (Quercus ilex L., Quercus pubescens Willd., and Pinus halepensis Mill.). For all species, a homeostasis of HSM in response to rainfall reduction was found, achieved through different mechanisms. For Q. ilex, the convergence in HSM is attributed to the adjustment of both the turgor loss point (Ψtlp) and the water potential at which 50% of xylem conductivity is lost due to embolism (P50). In contrast, the maintenance of HSM for P. halepensis and Q. pubescens is related to its isohydric behavior for the first and leaf area adjustment for the latter. It remains to be seen whether this HSM homeostasis can be generalized and if it will be sufficient to withstand extreme droughts expected in the Mediterranean region.
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Affiliation(s)
- Myriam Moreno
- INRAE, URFM, Avignon, France
- French Environment and Energy Management Agency, Angers, France
| | | | | | - Eric Badel
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, France
| | - Jesus Rodríguez-Calcerrada
- Research Group Functioning of Forest Systems in a Changing Environment, Universidad Politécnica de Madrid, Madrid, Spain
| | - Hervé Cochard
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, France
| | | | | | | | - Elena Ormeno
- Aix Marseille University, Avignon University, CNRS, IRD, IMBE, Marseille, France
| | | | - Catherine Fernandez
- Aix Marseille University, Avignon University, CNRS, IRD, IMBE, Marseille, France
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Gerolamo CS, Pereira L, Costa FRC, Jansen S, Angyalossy V, Nogueira A. Lianas in tropical dry seasonal forests have a high hydraulic efficiency but not always a higher embolism resistance than lianas in rainforests. ANNALS OF BOTANY 2024; 134:337-350. [PMID: 38721801 PMCID: PMC11232521 DOI: 10.1093/aob/mcae077] [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: 12/19/2023] [Accepted: 05/07/2024] [Indexed: 07/10/2024]
Abstract
BACKGROUND AND AIMS Lianas have higher relative abundance and biomass in drier seasonal forests than in rainforests, but whether this difference is associated with their hydraulic strategies is unclear. Here, we investigate whether lianas of seasonally dry forests are safer and more efficient in water transport than rainforest lianas, explaining patterns of liana abundance. METHODS We measured hydraulic traits on five pairs of congeneric lianas of the tribe Bignonieae in two contrasting forest sites: the wet 'Dense Ombrophilous Forest' in Central Amazonia (~2 dry months) and the drier 'Semideciduous Seasonal Forest' in the inland Atlantic Forest (~6 dry months). We also gathered a broader database, including 197 trees and 58 liana species from different tropical forests, to compare hydraulic safety between habits and forest types. KEY RESULTS Bignonieae lianas from both forests had high and similar hydraulic efficiency but exhibited variability in resistance to embolism across forest types when phylogenetic relationships were taken into account. Three genera had higher hydraulic safety in the seasonal forest than in the rainforest, but species across both forests had similar positive hydraulic safety margins despite lower predawn water potential values of seasonal forest lianas. We did not find the safety-efficiency trade-off. Merging our results with previously published data revealed a high variability of resistance to embolism in both trees and lianas, independent of forest types. CONCLUSIONS The high hydraulic efficiency of lianas detected here probably favours their rapid growth across tropical forests, but differences in hydraulic safety highlight that some species are highly vulnerable and may rely on other mechanisms to cope with drought. Future research on the lethal dehydration threshold and the connection between hydraulic resistance strategies and liana abundance could offer further insights into tropical forest dynamics under climatic threats.
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Affiliation(s)
- Caian S Gerolamo
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, 05508-090, Brazil
| | - Luciano Pereira
- Institute of Botany, Ulm University, Albert-Einstein-Allee 11, Ulm D-89081, Germany
| | - Flavia R C Costa
- Instituto Nacional de Pesquisas da Amazônia - INPA, Manaus, AM, 69011-970, Brazil
| | - Steven Jansen
- Institute of Botany, Ulm University, Albert-Einstein-Allee 11, Ulm D-89081, Germany
| | - Veronica Angyalossy
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, 05508-090, Brazil
| | - Anselmo Nogueira
- Centro de Ciências Naturais e Humanas (CCNH), Universidade Federal do ABC, São Bernardo do Campo, SP, 09606-070, Brazil
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Song C, Fu Y, Zhu S, Xu W, Ye Q, Yuan W. Linkages between stem vulnerability curves and tree demography and their implications for plant physiological modeling. TREE PHYSIOLOGY 2024; 44:tpae078. [PMID: 38959856 DOI: 10.1093/treephys/tpae078] [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: 01/05/2024] [Revised: 06/22/2024] [Accepted: 07/01/2024] [Indexed: 07/05/2024]
Abstract
Vulnerability curves (VCs) have been measured extensively to describe the differences in plant vulnerability to cavitation. Although the roles of hydraulic conductivity (Ks,max) and hydraulic safety (P50, embolism resistance), both of which are parameters of VCs ('sigmoidal' type), in tree demography have been evaluated across different forests, the direct linkages between VCs and tree demography are rarely explored. In this study, we combined measured VCs and plot data of 16 tree species in Panamanian seasonal tropical forests to investigate the connections between VCs and tree mortality, recruitment and growth. We found that the mortality and recruitment rates of evergreen species were most significantly positively correlated with P50. However, the mortality and recruitment rates of deciduous species only exhibited significant positive correlations with parameter a, which describes the steepness of VCs and indicates the sensitivity of conductivity loss with water potential decline, but is often neglected. These differences among evergreen and deciduous species may contribute to the poor performance of existing quantitative relationships (such as the fitting relationships for all 16 species) in capturing tree mortality and recruitment dynamics. Additionally, evergreen species presented a significant positive relationship between relative growth rate (RGR) and Ks,max, while deciduous species did not display such relationship. The RGR of both evergreen and deciduous species also displayed no significant correlations with P50 and a. Further analysis demonstrated that species with steeper VCs tended to have high mortality and recruitment rates, while species with flatter VCs were usually those with low mortality and recruitment rates. Our results highlight the important role of parameter a in tree demography, especially for deciduous species. Given that VC is a key component of plant hydraulic models, integrating measured VC rather than optimizing its parameters will help improve the ability to simulate and predict forest response to water availability.
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Affiliation(s)
- Chaoqing Song
- School of Atmospheric Sciences, Guangdong Province Data Center of Terrestrial and Marine Ecosystems Carbon Cycle, Sun Yat-Sen University, Daxue Road, Gaoxin District, Zhuhai, 519082, Guangdong, China
| | - Yangyang Fu
- School of Atmospheric Sciences, Guangdong Province Data Center of Terrestrial and Marine Ecosystems Carbon Cycle, Sun Yat-Sen University, Daxue Road, Gaoxin District, Zhuhai, 519082, Guangdong, China
| | - Shidan Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi University, Daxuedong Road 100, Xixiangtang District, Nanning, 530004, Guangxi, China
| | - Wenfang Xu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou, 510650, Guangdong, China
| | - Qing Ye
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou, 510650, Guangdong, China
| | - Wenping Yuan
- Institute of Carbon Neutrality, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Zhongguancun North Street 100, Haidian District, Beijing, 100871, China
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Zambonini D, Savi T, Rosner S, Petit G. Consistent decrease in conifer embolism resistance from the stem apex to base resulting from axial trends in tracheid and pit traits. FRONTIERS IN PLANT SCIENCE 2024; 15:1414448. [PMID: 38988629 PMCID: PMC11234846 DOI: 10.3389/fpls.2024.1414448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 06/03/2024] [Indexed: 07/12/2024]
Abstract
Introduction Drought-induced embolism formation in conifers is associated with several tracheid and pit traits, which vary in parallel from stem apex to base. We tested whether this axial anatomical variability is associated with a progressive variation in embolism vulnerability along the stem from apex to base. Methods We assessed the tracheid hydraulic diameter (Dh), mean pit membrane area (PMA) and the xylem pressure at 50% loss of conductivity (P50) on longitudinal stem segments extracted at different distances from the stem apex (DFA) in a Picea abies and an Abies alba tree. Results In both trees, Dh and PMA scaled with DFA 0.2. P50 varied for more than 3 MPa from the treetop to the stem base, according to a scaling of -P50 with DFA-0.2 . The largest Dh, PMA and P50 variation occurred for DFA<1.5 m. PMA and Dh scaled more than isometrically (exponent b=1.2). Pit traits vary proportionally with tracheid lumen diameter. Discussion and conclusions Apex-to-base trends in tracheid and pit traits, along with variations in P50, suggest a strong structure-function relationship that is influenced by DFA. Although the effect of DFA on P50 has not been extensively explored previously, we propose that analyzing the relationship between P50 and DFA could be crucial for a comprehensive assessment of embolism vulnerability at the individual level.
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Affiliation(s)
- Dario Zambonini
- Dept. Territorio e Sistemi Agro-Forestali, Università degli Studi di Padova, Legnaro (PD), Italy
| | - Tadeja Savi
- Department of Integrative Biology and Biodiversity Research, University of Natural Resources and Life Sciences, Vienna (BOKU), Institute of Botany, Vienna, Austria
| | - Sabine Rosner
- Department of Integrative Biology and Biodiversity Research, University of Natural Resources and Life Sciences, Vienna (BOKU), Institute of Botany, Vienna, Austria
| | - Giai Petit
- Dept. Territorio e Sistemi Agro-Forestali, Università degli Studi di Padova, Legnaro (PD), Italy
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West AG, Atkins K, van Blerk JJ, Skelton RP. Assessing vulnerability to embolism and hydraulic safety margins in reed-like Restionaceae. PLANT BIOLOGY (STUTTGART, GERMANY) 2024; 26:633-646. [PMID: 38588329 DOI: 10.1111/plb.13644] [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: 11/30/2023] [Accepted: 03/12/2024] [Indexed: 04/10/2024]
Abstract
The African Restionaceae (Poales), the dominant graminoid layer in the megadiverse Cape Floristic Region of South Africa, are distributed across a wide range of moisture availability, yet currently there is very little known about the underlying hydraulics of this group. We tested two methods for measuring culm vulnerability to embolism, the optical and pneumatic methods, in three species of Cannomois ranging in habitat from semi-riparian (Cannomois virgata) to dryland (Cannomois parviflora and C. congesta). Estimates of culm xylem vulnerability were coupled with measures of turgor loss point (ΨTLP) and minimum field water potential (ΨMD) to assess hydraulic safety margins. The optical and pneumatic methods produced similar estimates of P50, but differed for P12 and P88. All three species were quite vulnerable to embolism, with P50 of -1.9 MPa (C. virgata), -2.3 MPa (C. congesta), and -2.4 MPa (C. parviflora). Estimates of P50, ΨTLP and ΨMD aligned with habitat moisture stress, with highest values found in the semi-riparian C. virgata. Consistent differences in P50, ΨMD and ΨTLP between species resulted in consistent hydraulic safety margins across species of 0.96 ± 0.1 MPa between ΨMD and P50, with onset of embolism occurring 0.43 ± 0.04 MPa after ΨTLP for all three species. Our study demonstrates that restio occupancy of dry environments involves more than the evolution of highly resistant xylem, suggesting that other aspects of water relations are key to understanding trait-environment relationships in this group.
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Affiliation(s)
- A G West
- Department of Biological Sciences, University of Cape Town, Rondebosch, South Africa
| | - K Atkins
- Department of Biological Sciences, University of Cape Town, Rondebosch, South Africa
| | - J J van Blerk
- Department of Biological Sciences, University of Cape Town, Rondebosch, South Africa
| | - R P Skelton
- Fynbos Node, South African Environmental Observation Network, Newlands, South Africa
- Department of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa
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9
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Nardini A, Cochard H, Mayr S. Talk is cheap: rediscovering sounds made by plants. TRENDS IN PLANT SCIENCE 2024; 29:662-667. [PMID: 38218649 DOI: 10.1016/j.tplants.2023.11.023] [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: 09/22/2023] [Revised: 11/21/2023] [Accepted: 11/30/2023] [Indexed: 01/15/2024]
Abstract
A recent study and related commentaries have raised new interest in the phenomenon of ultrasonic sound production by plants exposed to stress, especially drought. While recent technological advancements have allowed the demonstration that these sounds can propagate in the air surrounding plants, we remind readers here that research on sound production by plants is more than 100 years old. The mechanisms and patterns of sound emission from plants subjected to different stress factors are also reasonably understood, thanks to the pioneering work of John Milburn and others. By contrast, experimental evidence for a role of these sounds in plant-animal or plant-plant communication remains lacking and, at present, these ideas remain highly speculative.
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Affiliation(s)
- Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste, Italy.
| | - Hervé Cochard
- Université Clermont-Auvergne, INRAE, PIAF, Clermont-Ferrand 63000, France
| | - Stefan Mayr
- Department of Botany, University of Innsbruck, 6020 Innsbruck, Austria
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10
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Tang W, Liu X, Liang X, Liu H, Yu K, He P, McAdam S, Zhao H, Ye Q. Hydraulic vulnerability difference between branches and roots increases with environmental aridity. Oecologia 2024; 205:177-190. [PMID: 38772916 DOI: 10.1007/s00442-024-05562-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 05/01/2024] [Indexed: 05/23/2024]
Abstract
The vulnerability of plant xylem to embolism can be described as the water potential at which xylem conductivity is lost by 50% (P50). According to the traditional hypothesis of hydraulic vulnerability segmentation, the difference in vulnerability to embolism between branches and roots is positive (P50 root-branch > 0). It is not clear whether this occurs broadly across species or how segmentation might vary across aridity gradients. We compiled hydraulic and anatomical datasets from branches and roots across 104 woody species (including new measurements from 10 species) in four biomes to investigate the relationships between P50 root-branch and environmental factors associated with aridity. We found a positive P50 root-branch relationship across species, and evidence that P50 root-branch increases with aridity. Branch xylem hydraulic conductivity transitioned from more efficient (e.g., wider conduit, higher hydraulic conductivity) to safer (e.g., narrower conduit, more negative P50) in response to the increase of aridity, while root xylem hydraulic conductivity remained unchanged across aridity gradients. Our results demonstrate that the hydraulic vulnerability difference between branches and roots is more positive in species from arid regions, largely driven by modifications to branch traits.
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Affiliation(s)
- Weize Tang
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaorong Liu
- Sichuan University of Arts and Science, Tashi Road 519, Dazhou, 635000, China
| | - Xingyun Liang
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
| | - Hui Liu
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
| | - Kailiang Yu
- High Meadows Environmental Institute, Princeton University, Princeton, NJ, USA
| | - Pengcheng He
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
| | - Scott McAdam
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - Han Zhao
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
| | - Qing Ye
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China.
- College of Life Sciences, Gannan Normal University, Ganzhou, 341000, China.
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11
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Jain P, Huber AE, Rockwell FE, Sen S, Holbrook NM, Stroock AD. New approaches to dissect leaf hydraulics reveal large gradients in living tissues of tomato leaves. THE NEW PHYTOLOGIST 2024; 242:453-465. [PMID: 38413216 DOI: 10.1111/nph.19585] [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: 08/22/2023] [Accepted: 01/22/2024] [Indexed: 02/29/2024]
Abstract
The water status of the living tissue in leaves is critical in determining plant function and global exchange of water and CO2. Despite significant advances in the past two decades, persistent questions remain about the tissue-specific origins of leaf hydraulic properties and their dependence on water status. We use a fluorescent nanoparticle reporter that provides water potential in the mesophyll apoplast adjacent to the epidermis of intact leaves to complement existing methods based on the Scholander Pressure Chamber (SPC). Working in tomato leaves, this approach provides access to the hydraulic conductance of the whole leaf, xylem, and outside-xylem tissues. These measurements show that, as stem water potential decreases, the water potential in the mesophyll apoplast can drop below that assessed with the SPC and can fall significantly below the turgor loss point of the leaf. We find that this drop in potential, dominated by the large loss (10-fold) of hydraulic conductance of the outside-xylem tissue, is not however strong enough to significantly limit transpiration. These observations highlight the need to reassess models of water transfer through the outside-xylem tissues, the potential importance of this tissue in regulating transpiration, and the power of new approaches for probing leaf hydraulics.
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Affiliation(s)
- Piyush Jain
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Annika E Huber
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Fulton E Rockwell
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Sabyasachi Sen
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - N Michele Holbrook
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Abraham D Stroock
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, 14853, USA
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12
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Jain P, Huber AE, Rockwell FE, Sen S, Holbrook NM, Stroock AD. Localized measurements of water potential reveal large loss of conductance in living tissues of maize leaves. PLANT PHYSIOLOGY 2024; 194:2288-2300. [PMID: 38128552 PMCID: PMC10980393 DOI: 10.1093/plphys/kiad679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 10/25/2023] [Accepted: 11/30/2023] [Indexed: 12/23/2023]
Abstract
The water status of the living tissue in leaves between the xylem and stomata (outside xylem zone (OXZ) plays a critical role in plant function and global mass and energy balance but has remained largely inaccessible. We resolve the local water relations of OXZ tissue using a nanogel reporter of water potential (ψ), AquaDust, that enables an in situ, nondestructive measurement of both ψ of xylem and highly localized ψ at the terminus of transpiration in the OXZ. Working in maize (Zea mays L.), these localized measurements reveal gradients in the OXZ that are several folds larger than those based on conventional methods and values of ψ in the mesophyll apoplast well below the macroscopic turgor loss potential. We find a strong loss of hydraulic conductance in both the bundle sheath and the mesophyll with decreasing xylem potential but not with evaporative demand. Our measurements suggest the OXZ plays an active role in regulating the transpiration path, and our methods provide the means to study this phenomenon.
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Affiliation(s)
- Piyush Jain
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Annika E Huber
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Fulton E Rockwell
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Sabyasachi Sen
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Noel Michele Holbrook
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Abraham D Stroock
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA
- School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853, USA
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13
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Zhu B, Guo P, Wu S, Yang Q, He F, Gao X, Zhang Y, Xiao J. A Better Fruit Quality of Grafted Blueberry Than Own-Rooted Blueberry Is Linked to Its Anatomy. PLANTS (BASEL, SWITZERLAND) 2024; 13:625. [PMID: 38475469 DOI: 10.3390/plants13050625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 02/19/2024] [Accepted: 02/22/2024] [Indexed: 03/14/2024]
Abstract
To further clarify the impact of different rootstocks in grafted blueberry, fruit quality, mineral contents, and leaf gas exchange were investigated in 'O'Neal' blueberry (Vaccinium corymbosum) grafted onto 'Anna' (V. corymbosum) (AO), 'Sharpblue' (V. corymbosum) (SO), 'Baldwin' (V. virgatum) (BO), 'Plolific' (V. virgatum) (PO), and 'Tifblue' (V. virgatum) (TO) rootstocks and own-rooted 'O'Neal' (NO), and differences in anatomic structures and drought resistance were determined in AO, TO, and NO. The findings revealed that fruit quality in TO and PO was excellent, that of BO and SO was good, and that of AO and NO was medium. 'Tifblue' and 'Plolific' rootstocks significantly increased the levels of leaf phosphorus and net photosynthetic rate of 'O'Neal', accompanied by a synchronous increase in their transpiration rates, stomatal conductance, and intercellular CO2. Additionally, the comprehensive evaluation scores from a principal component analysis based on anatomic structure traits from high to low were in the order TO > AO > NO. The P50 (xylem water potential at 50% loss of hydraulic conductivity) values of these grafted plants descended in the order NO > AO > TO, and the branch hydraulic conductivity of TO and sapwood hydraulic conductivity of TO and AO were significantly lower than those of NO. Thus, TO plants exhibited the strongest drought resistance, followed by AO, and NO, and this trait was related to the effects of different rootstocks on the fruit quality of 'O'Neal' blueberry. These results provided a basis for a deeper understanding of the interaction between rootstocks and scions, as well mechanisms to improve blueberry fruit quality.
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Affiliation(s)
- Bo Zhu
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, China
| | - Peipei Guo
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, China
| | - Shuangshuang Wu
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, China
| | - Qingjing Yang
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, China
| | - Feng He
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, China
| | - Xuan Gao
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, China
| | - Ya Zhang
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, China
| | - Jiaxin Xiao
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, China
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14
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Blystone S, Nuixe M, Traoré AS, Cochard H, Picon-Cochard C, Pagés G. Towards portable MRI in the plant sciences. PLANT METHODS 2024; 20:31. [PMID: 38369530 PMCID: PMC10874549 DOI: 10.1186/s13007-024-01152-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 02/05/2024] [Indexed: 02/20/2024]
Abstract
Plant physiology and structure are constantly changing according to internal and external factors. The study of plant water dynamics can give information on these changes, as they are linked to numerous plant functions. Currently, most of the methods used to study plant water dynamics are either invasive, destructive, or not easily accessible. Portable magnetic resonance imaging (MRI) is a field undergoing rapid expansion and which presents substantial advantages in the plant sciences. MRI permits the non-invasive study of plant water content, flow, structure, stress response, and other physiological processes, as a multitude of information can be obtained using the method, and portable devices make it possible to take these measurements in situ, in a plant's natural environment. In this work, we review the use of such devices applied to plants in climate chambers, greenhouses or in their natural environments. We also compare the use of portable MRI to other methods to obtain the same information and outline its advantages and disadvantages.
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Affiliation(s)
- Shannan Blystone
- Université Clermont Auvergne, INRAE, UR QuaPA, 63122, Saint-Genès-Champanelle, France
- INRAE, PROBE research infrastructure, AgroResonance facility, 63122, Saint-Genès-Champanelle, France
- Université Clermont Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
| | - Magali Nuixe
- Université Clermont Auvergne, INRAE, UR QuaPA, 63122, Saint-Genès-Champanelle, France
- INRAE, PROBE research infrastructure, AgroResonance facility, 63122, Saint-Genès-Champanelle, France
- Université Clermont Auvergne, INRAE, VetAgro Sup, UREP, 63000, Clermont-Ferrand, France
| | - Amidou Sissou Traoré
- Université Clermont Auvergne, INRAE, UR QuaPA, 63122, Saint-Genès-Champanelle, France
- INRAE, PROBE research infrastructure, AgroResonance facility, 63122, Saint-Genès-Champanelle, France
| | - Hervé Cochard
- Université Clermont Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
| | | | - Guilhem Pagés
- Université Clermont Auvergne, INRAE, UR QuaPA, 63122, Saint-Genès-Champanelle, France.
- INRAE, PROBE research infrastructure, AgroResonance facility, 63122, Saint-Genès-Champanelle, France.
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15
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Ávila-Lovera E, Haro R, Choudhary M, Acosta-Rangel A, Pratt RB, Santiago LS. The benefits of woody plant stem photosynthesis extend to hydraulic function and drought survival in Parkinsonia florida. TREE PHYSIOLOGY 2024; 44:tpae013. [PMID: 38284819 PMCID: PMC10918054 DOI: 10.1093/treephys/tpae013] [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: 06/09/2023] [Revised: 01/16/2024] [Accepted: 01/21/2024] [Indexed: 01/30/2024]
Abstract
As climate change exacerbates drought stress in many parts of the world, understanding plant physiological mechanisms for drought survival is critical to predicting ecosystem responses. Stem net photosynthesis, which is common in arid environments, may be a drought survival trait, but whether the additional carbon fixed by stems contributes to plant hydraulic function and drought survival in arid land plants is untested. We conducted a stem light-exclusion experiment on saplings of a widespread North American desert tree species, Parkinsonia florida L., and after shading acclimation, we then subjected half of the plants to a drought treatment to test the interaction between light exclusion and water limitation on growth, leaf and stem photosynthetic gas exchange, xylem embolism assessed with micro-computed tomography and gravimetric techniques, and survival. Growth, stem photosynthetic gas exchange, hydraulic function and survival all showed expected reductions in response to light exclusion. However, stem photosynthesis mitigated the drought-induced reductions in gas exchange, xylem embolism (percent loss of conductivity, PLC) and mortality. The highest mortality was in the combined light exclusion and drought treatment, and was related to stem PLC and native sapwood-specific hydraulic conductivity. This research highlights the integration of carbon economy and water transport. Our results show that additional carbon income by photosynthetic stems has an important role in the growth and survival of a widespread desert tree species during drought. This shift in function under conditions of increasing stress underscores the importance of considering stem photosynthesis for predicting drought-induced mortality not only for the additional supply of carbon, but also for its extended benefits for hydraulic function.
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Affiliation(s)
- Eleinis Ávila-Lovera
- School of Biological Sciences, The University of Utah, 257 S 1400 E, Salt Lake City, UT 84112, USA
- Department of Botany and Plant Sciences, University of California, 2150 Batchelor Hall, Riverside, CA 92521, USA
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancon, Panama, Republic of Panama
| | - Roxana Haro
- Department of Botany and Plant Sciences, University of California, 2150 Batchelor Hall, Riverside, CA 92521, USA
| | - Manika Choudhary
- Department of Botany and Plant Sciences, University of California, 2150 Batchelor Hall, Riverside, CA 92521, USA
| | - Aleyda Acosta-Rangel
- Department of Botany and Plant Sciences, University of California, 2150 Batchelor Hall, Riverside, CA 92521, USA
| | - R Brandon Pratt
- Department of Biology, California State University, 9001 Stockdale Hwy, Bakersfield, CA 93311, USA
| | - Louis S Santiago
- Department of Botany and Plant Sciences, University of California, 2150 Batchelor Hall, Riverside, CA 92521, USA
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancon, Panama, Republic of Panama
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16
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El-Sappah AH, Yan K, Li J. The plant is neither dumb nor deaf; it talks and hears. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024. [PMID: 38281239 DOI: 10.1111/tpj.16650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 01/03/2024] [Accepted: 01/18/2024] [Indexed: 01/30/2024]
Abstract
Animals and insects communicate using vibrations that are frequently too low or too high for human ears to detect. Plants and trees can communicate and sense sound. Khait et al. used a dependable recording system to capture airborne sounds produced by stressed plants. In addition to allowing plants to communicate their stress, sound aids in plant defense, development, and resilience. It also serves as a warning that danger is approaching. Demey et al. and others discussed the audit examinations that were conducted to investigate sound discernment in plants at the atomic and biological levels. The biological significance of sound in plants, the morphophysiological response of plants to sound, and the airborne noises that plants make and can hear from a few meters away were all discussed.
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Affiliation(s)
- Ahmed H El-Sappah
- College of Agriculture, Forestry, and Food Engineering, Yibin University, Yibin, Sichuan, China
- Department of Genetics, Faculty of Agriculture, Zagazig University, Zagazig, 44511, Egypt
| | - Kuan Yan
- College of Agriculture, Forestry, and Food Engineering, Yibin University, Yibin, Sichuan, China
| | - Jia Li
- College of Agriculture, Forestry, and Food Engineering, Yibin University, Yibin, Sichuan, China
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17
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Huang R, Di N, Xi B, Yang J, Duan J, Li X, Feng J, Choat B, Tissue D. Herb hydraulics: Variation and correlation for traits governing drought tolerance and efficiency of water transport. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:168095. [PMID: 37879470 DOI: 10.1016/j.scitotenv.2023.168095] [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: 07/10/2023] [Revised: 09/20/2023] [Accepted: 10/22/2023] [Indexed: 10/27/2023]
Abstract
Hydraulic traits dictate plant response to drought, thus enabling better understanding of community dynamics under global climate change. Despite being intensively documented in woody species, herbaceous species (graminoids and forbs) are largely understudied, hence the distribution and correlation of hydraulic traits in herbaceous species remains unclear. Here, we collected key hydraulic traits for 436 herbaceous species from published literature, including leaf hydraulic conductivity (Kleaf), water potential inducing 50 % loss of hydraulic conductivity (P50), stomatal closure (Pclose) and turgor loss (Ptlp). Trait variation of herbs was analyzed and contrasted with angiosperm woody species within the existing global hydraulic traits database, as well as between different growth forms within herbs. Furthermore, hydraulic traits coordination was also assessed for herbaceous species. We found that herbs showed overall more negative Pclose but less negative Ptlp compared with angiosperm woody species, while P50 did not differ between functional types, regardless of the organ (leaf and stem). In addition, correlations were found between Kleaf and P50 of leaf (P50leaf), as well as between Pclose, P50leaf and Kleaf. Within herbs, graminoids generally exhibited more negative P50 and Ptlp, but lower Kleaf, relative to forbs. Within herbs, no clear pattern regarding hydraulic traits-climate relationship was found. Our analysis provided insights into herb hydraulic, and highlighted the knowledge gaps need to be filled regarding the response of herbs to drought.
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Affiliation(s)
- Ruike Huang
- College of Life and Environmental Science, Minzu University of China, Zhongguancun Campus, 27 Zhongguancun south Avenue, Beijing 100081, People's Republic of China; Collaborative Innovation Center for Grassland Ecological Security (Jointly Supported by the Ministry of Education of China and Inner Mongolia Autonomous Region), Hohhot 010020, People's Republic of China
| | - Nan Di
- Collaborative Innovation Center for Grassland Ecological Security (Jointly Supported by the Ministry of Education of China and Inner Mongolia Autonomous Region), Hohhot 010020, People's Republic of China; School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, People's Republic of China
| | - Benye Xi
- Ministry of Education Key Laboratory of Silviculture and Conservation, Beijing Forestry University, 35 Qinghua East Rd, Beijing 100083, People's Republic of China
| | - Jinyan Yang
- CSIRO Land and Water, Black Mountain, Australian Capital Territory 2601, Australia
| | - Jie Duan
- Ministry of Education Key Laboratory of Silviculture and Conservation, Beijing Forestry University, 35 Qinghua East Rd, Beijing 100083, People's Republic of China.
| | - Ximeng Li
- College of Life and Environmental Science, Minzu University of China, Zhongguancun Campus, 27 Zhongguancun south Avenue, Beijing 100081, People's Republic of China.
| | - Jinchao Feng
- College of Life and Environmental Science, Minzu University of China, Zhongguancun Campus, 27 Zhongguancun south Avenue, Beijing 100081, People's Republic of China
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia
| | - David Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia; Global Centre for Land-Based Innovation, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia
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18
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Zhang C, Huang N, Zhang F, Wu T, He X, Wang J, Li Y. Intraspecific variations of leaf hydraulic, economic, and anatomical traits in Cinnamomum camphora along an urban-rural gradient. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166741. [PMID: 37659523 DOI: 10.1016/j.scitotenv.2023.166741] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/30/2023] [Accepted: 08/30/2023] [Indexed: 09/04/2023]
Abstract
Urbanization brings numerous benefits to residents, but it also introduces complex, variable, and heterogeneous habitat conditions to urban plants, resulting in an arid and hot urban environment that decreases tree growth and the ecological service capacity of trees. In this study, we evaluated leaf hydraulic, economic, and anatomical traits and their covariations of Cinnamomum camphora along an urban-rural gradient in Hefei, Eastern China. We found that Cinnamomum camphora in urban adopted a conservative hydraulic strategy with low leaf turgor loss point (Tlp), leaf hydraulic conductance (Kleaf), and leaf water potential resulting in 50 % loss of hydraulic conductance (P50), as well as a quick investment-return economic strategy with low unit leaf dry matter content (LMA) and high leaf nitrogen content (Leaf N). P50, Kleaf and LMA were significantly positively correlated with the urban-rural gradient (PC1urban-rural gradient), while Leaf N exhibited a negative correlation with it. The results showed a trade-off between intraspecific safety and efficiency in leaf hydraulic traits along the urban-rural gradient and an intraspecific coordinated variation in leaf hydraulic and economic traits. In addition, based on the analysis of a trait coordination network, it was revealed that leaf mesophyll and stomata were key structures for trait adjustment and coordination. Furthermore, our findings offer a significant theoretical underpinning for the effective management of landscape trees and the strategic planning of urban tree species.
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Affiliation(s)
- Cheng Zhang
- School of Forestry and Landscape Architecture, Anhui Agricultural University, Changjiang West Road 130, Shushan District, Hefei 230036, China
| | - Nuo Huang
- School of Forestry and Landscape Architecture, Anhui Agricultural University, Changjiang West Road 130, Shushan District, Hefei 230036, China
| | - Fengyu Zhang
- School of Forestry and Landscape Architecture, Anhui Agricultural University, Changjiang West Road 130, Shushan District, Hefei 230036, China
| | - Ting Wu
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia; Global Centre for Land-based Innovation, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia
| | - Xianjin He
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif sur Yvette 91191, France
| | - Jianan Wang
- School of Forestry and Landscape Architecture, Anhui Agricultural University, Changjiang West Road 130, Shushan District, Hefei 230036, China; Anhui Hefei Urban Ecosystem Research Station, National Forestry and Grassland Administration, Changjiang West Road 130, Shushan District, Hefei 230036, China
| | - Yiyong Li
- School of Forestry and Landscape Architecture, Anhui Agricultural University, Changjiang West Road 130, Shushan District, Hefei 230036, China; Anhui Hefei Urban Ecosystem Research Station, National Forestry and Grassland Administration, Changjiang West Road 130, Shushan District, Hefei 230036, China.
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19
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Laughlin DC, Siefert A, Fleri JR, Tumber-Dávila SJ, Hammond WM, Sabatini FM, Damasceno G, Aubin I, Field R, Hatim MZ, Jansen S, Lenoir J, Lens F, McCarthy JK, Niinemets Ü, Phillips OL, Attorre F, Bergeron Y, Bruun HH, Byun C, Ćušterevska R, Dengler J, De Sanctis M, Dolezal J, Jiménez-Alfaro B, Hérault B, Homeier J, Kattge J, Meir P, Mencuccini M, Noroozi J, Nowak A, Peñuelas J, Schmidt M, Škvorc Ž, Sultana F, Ugarte RM, Bruelheide H. Rooting depth and xylem vulnerability are independent woody plant traits jointly selected by aridity, seasonality, and water table depth. THE NEW PHYTOLOGIST 2023; 240:1774-1787. [PMID: 37743552 DOI: 10.1111/nph.19276] [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: 07/05/2023] [Accepted: 08/29/2023] [Indexed: 09/26/2023]
Abstract
Evolutionary radiations of woody taxa within arid environments were made possible by multiple trait innovations including deep roots and embolism-resistant xylem, but little is known about how these traits have coevolved across the phylogeny of woody plants or how they jointly influence the distribution of species. We synthesized global trait and vegetation plot datasets to examine how rooting depth and xylem vulnerability across 188 woody plant species interact with aridity, precipitation seasonality, and water table depth to influence species occurrence probabilities across all biomes. Xylem resistance to embolism and rooting depth are independent woody plant traits that do not exhibit an interspecific trade-off. Resistant xylem and deep roots increase occurrence probabilities in arid, seasonal climates over deep water tables. Resistant xylem and shallow roots increase occurrence probabilities in arid, nonseasonal climates over deep water tables. Vulnerable xylem and deep roots increase occurrence probabilities in arid, nonseasonal climates over shallow water tables. Lastly, vulnerable xylem and shallow roots increase occurrence probabilities in humid climates. Each combination of trait values optimizes occurrence probabilities in unique environmental conditions. Responses of deeply rooted vegetation may be buffered if evaporative demand changes faster than water table depth under climate change.
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Affiliation(s)
- Daniel C Laughlin
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - Andrew Siefert
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - Jesse R Fleri
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | | | - William M Hammond
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
| | - Francesco Maria Sabatini
- BIOME Lab, Department of Biological, Geological and Environmental Sciences (BiGeA), Alma Mater Studiorum University of Bologna, Via Irnerio 42, 40126, Bologna, Italy
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21, Praha 6, Suchdol, Czech Republic
| | - Gabriella Damasceno
- German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig, Leipzig, 04103, Germany
- Institute of Biology and Geobotany and Botanical Garden, Martin-Luther University, Halle-Wittenberg, Halle, 06108, Germany
| | - Isabelle Aubin
- Great Lakes Forestry Centre, Canadian Forest Service, Natural Resources Canada, Sault Ste. Marie, Ontario, P6A 2E5, Canada
| | - Richard Field
- School of Geography, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Mohamed Z Hatim
- Plant Ecology and Nature Conservation Group, Environmental Sciences Department, Wageningen University and Research, 6700 AA, Wageningen, the Netherlands
- Botany and Microbiology Department, Tanta University, Tanta, 3527, Egypt
| | - Steven Jansen
- Institute of Botany, Ulm University, Albert-Einstein-Allee 11, Ulm, 89081, Germany
| | - Jonathan Lenoir
- UMR CNRS 7058, Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN), Université de Picardie Jules Verne, 80000, Amiens, France
| | - Frederic Lens
- Naturalis Biodiversity Center, Darwinweg 2, 2333 CR, Leiden, the Netherlands
- Plant Sciences, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE, Leiden, the Netherlands
| | | | - Ülo Niinemets
- Crop Science and Plant Biology, Estonian University of Life Sciences, Tartu, 51006, Estonia
| | | | - Fabio Attorre
- Department of Environmental Biology, Sapienza University of Rome, Rome, 00185, Italy
| | - Yves Bergeron
- Institut de recherche sur les forêts Université du Québec en Abitibi-Témiscamingue, 445 boul. de l'université, Rouyn-Noranda, Québec, J9X5E4, Canada
| | - Hans Henrik Bruun
- Department of Biology, University of Copenhagen, 2100, Copenhagen Ø, Denmark
| | - Chaeho Byun
- Department of Biological Science, Andong National University, Andong-si, 36729, South Korea
| | - Renata Ćušterevska
- Institute of Biology, Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University, 1000, Skopje, North Macedonia
| | - Jürgen Dengler
- Vegetation Ecology Research Group, Institute of Natural Resource Sciences (IUNR), Zurich University of Applied Sciences (ZHAW), 8820, Wädenswil, Switzerland
- Plant Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, 95447, Bayreuth, Germany
| | - Michele De Sanctis
- Department of Environmental Biology, Sapienza University of Rome, Rome, 00185, Italy
| | - Jiri Dolezal
- Department of Functional Ecology, Institute of Botany, Czech Academy of Sciences, Trebon, Czech Republic
- Department of Botany, Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic
| | - Borja Jiménez-Alfaro
- Biodiversity Research Institute (Univ. Oviedo-CSIC-Princ. Asturias), Mieres, Asturias, Spain
| | - Bruno Hérault
- CIRAD, UPR Forêts et Sociétés, F-34398, Montpellier, France
- Forêts et Sociétés, Univ Montpellier, CIRAD, Montpellier, France
| | - Jürgen Homeier
- Plant Ecology and Ecosystems Research, University of Goettingen, 37073, Goettingen, Germany
- Resource Management, HAWK University of Applied Sciences and Arts, 37077, Goettingen, Germany
| | - Jens Kattge
- German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig, Leipzig, 04103, Germany
- Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Patrick Meir
- School of Geosciences, University of Edinburgh, Edinburgh, UK
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Maurizio Mencuccini
- CREAF, Cerdanyola del Vallès, 08193, Barcelona, Catalonia, Spain
- ICREA, 08010, Barcelona, Spain
| | - Jalil Noroozi
- Department of Botany and Biodiversity Research, Universitiy of Vienna, 1030, Vienna, Austria
| | - Arkadiusz Nowak
- Botanical Garden, Polish Academy of Sciences, Warsaw, Poland
- Department of Botany and Nature Protection, University of Warmia and Mazury, Olsztyn, Poland
| | - Josep Peñuelas
- CREAF, Cerdanyola del Vallès, 08193, Barcelona, Catalonia, Spain
- Global Ecology Unit CREAF-CSIC-UAB, CSIC, Bellaterra, 08193, Barcelona, Catalonia, Spain
| | - Marco Schmidt
- Palmengarten der Stadt Frankfurt am Main, 60323, Frankfurt am Main, Germany
| | - Željko Škvorc
- Faculty of Forestry and Wood Technology, University of Zagreb, 10000, Zagreb, Croatia
| | - Fahmida Sultana
- Department of Forestry and Environmental Science, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Rosina Magaña Ugarte
- Botany Unit, Department of Pharmacology, Pharmacognosy and Botany, Faculty of Pharmacy, Universidad Complutense de Madrid, Madrid, Spain
| | - Helge Bruelheide
- German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig, Leipzig, 04103, Germany
- Institute of Biology and Geobotany and Botanical Garden, Martin-Luther University, Halle-Wittenberg, Halle, 06108, Germany
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20
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Paligi SS, Link RM, Isasa E, Bittencourt P, Cabral JS, Jansen S, Oliveira RS, Pereira L, Schuldt B. Assessing the agreement between the pneumatic and the flow-centrifuge method for estimating xylem safety in temperate diffuse-porous tree species. PLANT BIOLOGY (STUTTGART, GERMANY) 2023; 25:1171-1185. [PMID: 37703535 DOI: 10.1111/plb.13573] [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: 03/16/2023] [Accepted: 07/06/2023] [Indexed: 09/15/2023]
Abstract
The increasing frequency of global change-type droughts has created a need for fast, accurate and widely applicable techniques for estimating xylem embolism resistance to improve forecasts of future forest changes. We used data from 12 diffuse-porous temperate tree species covering a wide range of xylem safety to compare the pneumatic and flow-centrifuge method, two rapid methods used for constructing xylem vulnerability curves. We evaluated the agreement between parameters estimated with both methods and the sensitivity of pneumatic measurements to the duration of air discharge (AD) measurements. There was close agreement between xylem water potentials at 50% air discharged (PAD), estimated with the Pneumatron, and 50% loss of hydraulic conductivity (PLC), estimated with the flow-centrifuge method (mean signed deviation: 0.12 MPa, Pearson correlation: 0.96 after 15 s of gas extraction). However, the relationship between the estimated slopes was more variable, resulting in lower agreement in the xylem water potential at 12% and 88% PAD/PLC. The agreement between the two methods was not affected by species-specific vessel length distributions. All pneumatic parameters were sensitive to AD time. Overall agreement was highest at relatively short AD times, with an optimum at 16 s. Our results highlight the value of the Pneumatron as an easy and reliable tool to estimate 50% embolism thresholds for a wide range of diffuse-porous temperate angiosperms. Further, our study provides a set of useful metrics for methodological comparisons of vulnerability curves in terms of systematic and random deviations, as well as overall agreement.
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Affiliation(s)
- S S Paligi
- Chair of Ecophysiology and Vegetation Ecology, Julius-von-Sachs Institute of Biological Sciences, University of Würzburg, Würzburg, Germany
| | - R M Link
- Chair of Ecophysiology and Vegetation Ecology, Julius-von-Sachs Institute of Biological Sciences, University of Würzburg, Würzburg, Germany
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technische Universität Dresden, Tharandt, Germany
| | - E Isasa
- Chair of Ecophysiology and Vegetation Ecology, Julius-von-Sachs Institute of Biological Sciences, University of Würzburg, Würzburg, Germany
| | - P Bittencourt
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - J S Cabral
- Ecosystem Modeling Group, Center for Computational and Theoretical Biology, University of Würzburg, Würzburg, Germany
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK
| | - S Jansen
- Institute of Botany, Ulm University, Ulm, Germany
| | - R S Oliveira
- Department of Plant Biology, Instituto de Biologia, University of Campinas, Campinas, SP, Brazil
| | - L Pereira
- Institute of Botany, Ulm University, Ulm, Germany
| | - B Schuldt
- Chair of Ecophysiology and Vegetation Ecology, Julius-von-Sachs Institute of Biological Sciences, University of Würzburg, Würzburg, Germany
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technische Universität Dresden, Tharandt, Germany
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21
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Krieger L, Schymanski SJ. A new experimental setup to measure hydraulic conductivity of plant segments. AOB PLANTS 2023; 15:plad024. [PMID: 37576875 PMCID: PMC10418303 DOI: 10.1093/aobpla/plad024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 04/07/2023] [Accepted: 05/15/2023] [Indexed: 08/15/2023]
Abstract
Plant hydraulic conductivity and its decline under water stress are the focal point of current plant hydraulic research. The common methods of measuring hydraulic conductivity control a pressure gradient to push water through plant samples, submitting them to conditions far away from those that are experienced in nature where flow is suction driven and determined by the leaf water demand. In this paper, we present two methods for measuring hydraulic conductivity under closer to natural conditions, an artificial plant setup and a horizontal syringe pump setup. Both approaches use suction to pull water through a plant sample while dynamically monitoring the flow rate and pressure gradients. The syringe setup presented here allows for controlling and rapidly changing flow and pressure conditions, enabling experimental assessment of rapid plant hydraulic responses to water stress. The setup also allows quantification of dynamic changes in water storage of plant samples. Our tests demonstrate that the syringe pump setup can reproduce hydraulic conductivity values measured using the current standard method based on pushing water under above-atmospheric pressure. Surprisingly, using both the traditional and our new syringe pump setup, we found a positive correlation between changes in flow rate and hydraulic conductivity. Moreover, when flow or pressure conditions were changed rapidly, we found substantial contributions to flow by dynamic and largely reversible changes in the water storage of plant samples. Although the measurements can be performed under sub-atmospheric pressures, it is not possible to subject the samples to negative pressures due to the presence of gas bubbles near the valves and pressure sensors. Regardless, this setup allows for unprecedented insights into the interplay between pressure, flow rate, hydraulic conductivity and water storage in plant segments. This work was performed using an Open Science approach with the original data and analysis to be found at https://doi.org/10.5281/zenodo.7322605.
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Affiliation(s)
- Louis Krieger
- Environmental Research and Innovation, Luxembourg Institute of Science and Technology, 41 Rue du Brill, 4422 Belvaux, Luxembourg
- Faculty of Science, Technology and Medicine, University of Luxembourg, 2 Av. de l’Universite, 4365 Esch-sur-Alzette, Luxembourg
| | - Stanislaus J Schymanski
- Environmental Research and Innovation, Luxembourg Institute of Science and Technology, 41 Rue du Brill, 4422 Belvaux, Luxembourg
- Faculty of Science, Technology and Medicine, University of Luxembourg, 2 Av. de l’Universite, 4365 Esch-sur-Alzette, Luxembourg
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22
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Carluccio G, Greco D, Sabella E, Vergine M, De Bellis L, Luvisi A. Xylem Embolism and Pathogens: Can the Vessel Anatomy of Woody Plants Contribute to X. fastidiosa Resistance? Pathogens 2023; 12:825. [PMID: 37375515 DOI: 10.3390/pathogens12060825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/07/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
The maintenance of an intact water column in the xylem lumen several meters above the ground is essential for woody plant viability. In fact, abiotic and biotic factors can lead to the formation of emboli in the xylem, interrupting sap flow and causing consequences on the health status of the plant. Anyway, the tendency of plants to develop emboli depends on the intrinsic features of the xylem, while the cyto-histological structure of the xylem plays a role in resistance to vascular pathogens, as in the case of the pathogenic bacterium Xylella fastidiosa. Analysis of the scientific literature suggests that on grapevine and olive, some xylem features can determine plant tolerance to vascular pathogens. However, the same trend was not reported in citrus, indicating that X. fastidiosa interactions with host plants differ by species. Unfortunately, studies in this area are still limited, with few explaining inter-cultivar insights. Thus, in a global context seriously threatened by X. fastidiosa, a deeper understanding of the relationship between the physical and mechanical characteristics of the xylem and resistance to stresses can be useful for selecting cultivars that may be more resistant to environmental changes, such as drought and vascular pathogens, as a way to preserve agricultural productions and ecosystems.
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Affiliation(s)
- Giambattista Carluccio
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Davide Greco
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
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23
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Férriz M, Martin-Benito D, Fernández-de-Simón MB, Conde M, García-Cervigón AI, Aranda I, Gea-Izquierdo G. Functional phenotypic plasticity mediated by water stress and [CO2] explains differences in drought tolerance of two phylogenetically close conifers. TREE PHYSIOLOGY 2023; 43:909-924. [PMID: 36809504 PMCID: PMC10255776 DOI: 10.1093/treephys/tpad021] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 02/15/2023] [Indexed: 06/11/2023]
Abstract
Forests are threatened globally by increased recurrence and intensity of hot droughts. Functionally close coexisting species may exhibit differences in drought vulnerability large enough to cause niche differentiation and affect forest dynamics. The effect of rising atmospheric [CO2], which could partly alleviate the negative effects of drought, may also differ between species. We analysed functional plasticity in seedlings of two taxonomically close pine species (Pinus pinaster Ait., Pinus pinea L.) under different [CO2] and water stress levels. The multidimensional functional trait variability was more influenced by water stress (preferentially xylem traits) and [CO2] (mostly leaf traits) than by differences between species. However, we observed differences between species in the strategies followed to coordinate their hydraulic and structural traits under stress. Leaf 13C discrimination decreased with water stress and increased under elevated [CO2]. Under water stress both species increased their sapwood area to leaf area ratios, tracheid density and xylem cavitation, whereas they reduced tracheid lumen area and xylem conductivity. Pinus pinea was more anisohydric than P. pinaster. Pinus pinaster produced larger conduits under well-watered conditions than P. pinea. Pinus pinea was more tolerant to water stress and more resistant to xylem cavitation under low water potentials. The higher xylem plasticity in P. pinea, particularly in tracheid lumen area, expressed a higher capacity of acclimation to water stress than P. pinaster. In contrast, P. pinaster coped with water stress comparatively more by increasing plasticity of leaf hydraulic traits. Despite the small differences observed in the functional response to water stress and drought tolerance between species, these interspecific differences agreed with ongoing substitution of P. pinaster by P. pinea in forests where both species co-occur. Increased [CO2] had little effect on the species-specific relative performance. Thus, a competitive advantage under moderate water stress of P. pinea compared with P. pinaster is expected to continue in the future.
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Affiliation(s)
- M Férriz
- ICIFOR-INIA, CSIC. Ctra La Coruña km 7.5, 28040 Madrid, Spain
| | - D Martin-Benito
- ICIFOR-INIA, CSIC. Ctra La Coruña km 7.5, 28040 Madrid, Spain
| | | | - M Conde
- ICIFOR-INIA, CSIC. Ctra La Coruña km 7.5, 28040 Madrid, Spain
| | - A I García-Cervigón
- Department of Biology and Geology, Physics and Inorganic Chemistry Rey Juan Carlos University, c/Tulipán s/n, 28933 Móstoles, Spain
| | - I Aranda
- ICIFOR-INIA, CSIC. Ctra La Coruña km 7.5, 28040 Madrid, Spain
| | - G Gea-Izquierdo
- ICIFOR-INIA, CSIC. Ctra La Coruña km 7.5, 28040 Madrid, Spain
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24
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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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25
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Khait I, Lewin-Epstein O, Sharon R, Saban K, Goldstein R, Anikster Y, Zeron Y, Agassy C, Nizan S, Sharabi G, Perelman R, Boonman A, Sade N, Yovel Y, Hadany L. Sounds emitted by plants under stress are airborne and informative. Cell 2023; 186:1328-1336.e10. [PMID: 37001499 DOI: 10.1016/j.cell.2023.03.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 11/29/2022] [Accepted: 03/06/2023] [Indexed: 04/01/2023]
Abstract
Stressed plants show altered phenotypes, including changes in color, smell, and shape. Yet, airborne sounds emitted by stressed plants have not been investigated before. Here we show that stressed plants emit airborne sounds that can be recorded from a distance and classified. We recorded ultrasonic sounds emitted by tomato and tobacco plants inside an acoustic chamber, and in a greenhouse, while monitoring the plant's physiological parameters. We developed machine learning models that succeeded in identifying the condition of the plants, including dehydration level and injury, based solely on the emitted sounds. These informative sounds may also be detectable by other organisms. This work opens avenues for understanding plants and their interactions with the environment and may have significant impact on agriculture.
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Affiliation(s)
- Itzhak Khait
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Ohad Lewin-Epstein
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Raz Sharon
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel; School of Mathematical Sciences, Tel-Aviv University, Tel-Aviv, Israel
| | - Kfir Saban
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Revital Goldstein
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Yehuda Anikster
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Yarden Zeron
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Chen Agassy
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Shaked Nizan
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Gayl Sharabi
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Ran Perelman
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel
| | - Arjan Boonman
- School of Zoology, Tel-Aviv University, Tel-Aviv, Israel
| | - Nir Sade
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel; The Institute of Cereal Crop Improvement, Tel Aviv University, Tel Aviv, Israel
| | - Yossi Yovel
- School of Zoology, Tel-Aviv University, Tel-Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel-Aviv, Israel
| | - Lilach Hadany
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel-Aviv, Israel.
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26
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Wang X, Fan Y, Zhang C, Zhao Y, Du G, Li M, Si B. From comfort zone to mortality: Sequence of physiological stress thresholds in Robinia pseudoacacia seedlings during progressive drought. FRONTIERS IN PLANT SCIENCE 2023; 14:1149760. [PMID: 37008484 PMCID: PMC10060868 DOI: 10.3389/fpls.2023.1149760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 02/27/2023] [Indexed: 06/19/2023]
Abstract
INTRODUCTION Parameterizing the process of trees from the comfort zone to mortality during progressive drought is important for, but is not well represented in, vegetation models, given the lack of appropriate indices to gauge the response of trees to droughts. The objective of this study was to determine reliable and readily available tree drought stressindices and the thresholds at which droughts activate important physiological responses. METHODS We analyzed the changes in the transpiration (T), stomatal conductance, xylem conductance, and leaf health status due to a decrease in soil water availability (SWA), predawn xylem water potential (ψpd), and midday xylem water potential (ψmd) in Robinia pseudoacacia seedlings during progressive drought. RESULTS The results showed that ψmd was a better indicator of drought stress than SWA and ψpd, because ψmd was more closely related to the physiological response (defoliation and xylem embolization) during severe drought and could be measured more conveniently. We derived the following five stress levels from the observed responses to decreasing ψmd: comfort zone (ψmd > -0.9 MPa), wherein transpiration and stomatal conductance are not limited by SWA; moderate drought stress (-0.9 to -1.75 MPa), wherein transpiration and stomatal conductance are limited by drought; high drought stress (-1.75 to -2.59 MPa), wherein transpiration decreases significantly (T< 10%) and stomata closes completely; severe drought stress (-2.59 to -4.02 MPa), wherein transpiration ceases (T< 0.1%) and leaf shedding orwilting is > 50%; and extreme drought stress (< -4.02 MPa), leading to tree mortality due to xylem hydraulic failure. DISCUSSION To our knowledge, our scheme is the first to outline the quantitative thresholds for the downregulation of physiological processes in R. pseudoacacia during drought, therefore, can be used to synthesize valuable information for process-based vegetation models.
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Affiliation(s)
- Xia Wang
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, China
| | - Yanli Fan
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, China
| | - Congcong Zhang
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, China
| | - Yihong Zhao
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, China
| | - Guangyuan Du
- College of Science, Northwest A&F University, Yangling, China
| | - Min Li
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, China
| | - Bingcheng Si
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, China
- Department of Soil Science, University of Saskatchewan, Saskatoon, SK, Canada
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27
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Yang D, Pereira L, Peng G, Ribeiro RV, Kaack L, Jansen S, Tyree MT. A unit pipe pneumatic model to simulate gas kinetics during measurements of embolism in excised angiosperm xylem. TREE PHYSIOLOGY 2023; 43:88-101. [PMID: 36049079 DOI: 10.1093/treephys/tpac105] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 08/30/2022] [Indexed: 06/15/2023]
Abstract
The pneumatic method has been introduced to quantify embolism resistance in plant xylem of various organs by applying a partial vacuum to cut-open xylem. Despite the similarity in vulnerability curves between the pneumatic and other methods, a modeling approach is needed to investigate if changes in xylem embolism during dehydration can be accurately quantified based on gas diffusion kinetics. Therefore, a unit pipe pneumatic (UPPn) model was developed to estimate gas extraction from intact conduits, which were axially interconnected by inter-conduit pit membranes to cut-open conduits. The physical laws used included Fick's law for diffusion, Henry's law for gas concentration partitioning between liquid and gas phases at equilibrium and the ideal gas law. The UPPn model showed that 91% of the extracted gas came from the first five series of embolized, intact conduits and only 9% from the aqueous phase after 15 s of simulation. Considering alternative gas sources, embolism resistance measured with a pneumatron device was systematically overestimated by 2-17%, which corresponded to a typical measuring error of 0.11 MPa for P50 (the water potential equivalent to 50% of the maximum amount of gas extracted). It is concluded that pneumatic vulnerability curves directly measure embolism of intact conduits due to the fast movement of gas across interconduit pit membranes, while gas extraction from sap and diffusion across hydrated cell walls is about 100 times slower. We expect that the UPPn model will also contribute to the understanding of embolism propagation based on temporal gas dynamics.
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Affiliation(s)
- Dongmei Yang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Luciano Pereira
- Laboratory of Crop Physiology, Department of Plant Biology, Institute of Biology, P.O. Box 6109, University of Campinas (UNICAMP), Campinas 13083-970, Brazil
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11 Ulm D-89081, Germany
| | - Guoquan Peng
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Rafael V Ribeiro
- Laboratory of Crop Physiology, Department of Plant Biology, Institute of Biology, P.O. Box 6109, University of Campinas (UNICAMP), Campinas 13083-970, Brazil
| | - Lucian Kaack
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11 Ulm D-89081, Germany
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11 Ulm D-89081, Germany
| | - Melvin T Tyree
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
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28
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Chen YJ, Maenpuen P, Zhang JL, Zhang YJ. Remaining uncertainties in the Pneumatic method. THE NEW PHYTOLOGIST 2023; 237:384-391. [PMID: 36537302 DOI: 10.1111/nph.18530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 10/01/2022] [Indexed: 06/17/2023]
Affiliation(s)
- Ya-Jun Chen
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
- Yuanjiang Savanna Ecosystem Research Station, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Yuanjiang, Yunnan, 653300, China
| | - Phisamai Maenpuen
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jiao-Lin Zhang
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Yong-Jiang Zhang
- School of Biology and Ecology, University of Maine, Orono, ME, 04469, USA
- Climate Change Institute, University of Maine, Orono, ME, 04469, USA
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29
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Trifilò P, Abate E, Petruzzellis F, Azzarà M, Nardini A. Critical water contents at leaf, stem and root level leading to irreversible drought-induced damage in two woody and one herbaceous species. PLANT, CELL & ENVIRONMENT 2023; 46:119-132. [PMID: 36266962 DOI: 10.1111/pce.14469] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/11/2022] [Accepted: 10/16/2022] [Indexed: 06/16/2023]
Abstract
Plant water content is a simple and promising parameter for monitoring drought-driven plant mortality risk. However, critical water content thresholds leading to cell damage and plant failure are still unknown. Moreover, it is unclear whether whole-plant or a specific organ water content is the most reliable indicator of mortality risk. We assessed differences in dehydration thresholds in leaf, stem and root samples, hampering the organ-specific rehydration capacity and increasing the mortality risk. We also tested eventual differences between a fast experimental dehydration of uprooted plants, compared to long-term water stress induced by withholding irrigation in potted plants. We investigated three species with different growth forms and leaf habits i.e., Helianthus annuus (herbaceous), Populus nigra (deciduous tree) and Quercus ilex (evergreen tree). Results obtained by the two dehydration treatments largely overlapped, thus validating bench dehydration as a fast but reliable method to assess species-specific critical water content thresholds. Regardless of the organ considered, a relative water content value of 60% induced significant cell membrane damage and loss of rehydration capacity, thus leading to irreversible plant failure and death.
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Affiliation(s)
- Patrizia Trifilò
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Messina, Italy
| | - Elisa Abate
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Messina, Italy
| | | | - Maria Azzarà
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Messina, Italy
| | - Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Trieste, Italy
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Xu GQ, Chen TQ, Liu SS, Ma J, Li Y. Within-crown plasticity of hydraulic properties influence branch dieback patterns of two woody plants under experimental drought conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 854:158802. [PMID: 36115397 DOI: 10.1016/j.scitotenv.2022.158802] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 09/11/2022] [Accepted: 09/12/2022] [Indexed: 06/15/2023]
Abstract
In recent year, widespread declines of Populus bolleana Lauche trees (P. bolleana, which dieback from the top down) and Haloxylon ammodendron shrubs (H. ammodendron, which dieback starting from their outer canopy) have occurred. To investigate how both intra-canopy hydraulic changes and plasticity in hydraulic properties create differences in vulnerability between these two species, we conducted a drought simulation field experiment. We analyzed branch hydraulic vulnerability, leaf water potential (Ψ), photosynthesis (A), stomatal conductance (gs), non-structural carbohydrate (NSCs) contents and morphological traits of the plants as the plants underwent a partial canopy dieback. Our results showed that: (1) the hydraulic architecture was very different between the two life forms; (2) H. ammodendron exhibited a drought tolerance response with weak stomatal control, and thus a sharp decline in Ψ while P. bolleana showed a drought avoidance response with tighter stomatal control that maintained a relatively stable Ψ; (3) the Ψ of H. ammodendron showed relative consistent symptoms of drought stress with increasing plant stature, but the Ψ of P. bolleana showed greater drought stress in higher portions of the crown; (4) prolonged drought caused P. bolleana to consume and H. ammodendron to accumulate NSCs in the branches of their upper canopy. Thus, the prolonged drought caused the shoots of the upper canopy of P. bolleana to experience greater vulnerability leading to dieback of the upper branches first, while all the twigs of the outer canopy of H. ammodendron experienced nearly identical degrees of vulnerability, and thus dieback occurred uniformly. Our results indicate that intra-canopy hydraulic change and their plasticity under drought was the main cause of the observed canopy dieback patterns in both species. However, more work is needed to further establish that hydraulic limitation as a function of plant stature was the sole mechanism for causing the divergent canopy dieback patterns.
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Affiliation(s)
- Gui-Qing Xu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Tu-Qiang Chen
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shen-Si Liu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jie Ma
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China
| | - Yan Li
- State Key Lab of Subtropical Siviculture, Zhejiang A&F University, 666Wusu Street, Lin-An, Hangzhou 311300, China
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31
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Petruzzellis F, Tordoni E, Di Bonaventura A, Tomasella M, Natale S, Panepinto F, Bacaro G, Nardini A. Turgor loss point and vulnerability to xylem embolism predict species-specific risk of drought-induced decline of urban trees. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:1198-1207. [PMID: 34704333 PMCID: PMC10078640 DOI: 10.1111/plb.13355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
Increasing frequency and severity of drought events is posing risks to trees' health, including those planted in urban settlements. Drought-induced decline of urban trees negatively affects ecosystem services of urban green spaces and implies cost for maintenance and removal of plants. We aimed at identifying physiological traits that can explain and predict the species-specific vulnerability to climate change in urban habitats. We assessed the relationships between long-term risk of decline of different tree species in a medium-sized town and their key indicators of drought stress tolerance, i.e. turgor loss point (TLP) and vulnerability to xylem embolism (P50 ). Starting from 2012, the study area experienced several summer seasons with positive anomalies of temperature and negative anomalies of precipitation. This trend was coupled with increasing percentages of urban trees showing signs of crown die-back and mortality. The species-specific risk of decline was higher for species with less negative TLP and P50 values. The relationship between species-specific risk of climate change-induced decline of urban trees and key physiological indicators of drought tolerance confirms findings obtained in natural forests and highlights that TLP and P50 are useful indicators for species selection for tree plantation in towns, to mitigate negative impacts of climate change.
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Affiliation(s)
- F. Petruzzellis
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
- Dipartimento di Scienze agroalimentari, ambientali e animaliUniversità di UdineUdineItalia
| | - E. Tordoni
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
- Institute of Ecology and Earth ScienceUniversity of TartuTartuEstonia
| | - A. Di Bonaventura
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
| | - M. Tomasella
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
| | - S. Natale
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
| | - F. Panepinto
- Unità Tecnica Alberature e ParchiServizio Strade e Verde PubblicoComune di TriesteTriesteItalia
| | - G. Bacaro
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
| | - A. Nardini
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
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Vargas G. G, Kunert N, Hammond WM, Berry ZC, Werden LK, Smith‐Martin CM, Wolfe BT, Toro L, Mondragón‐Botero A, Pinto‐Ledezma JN, Schwartz NB, Uriarte M, Sack L, Anderson‐Teixeira KJ, Powers JS. Leaf habit affects the distribution of drought sensitivity but not water transport efficiency in the tropics. Ecol Lett 2022; 25:2637-2650. [PMID: 36257904 PMCID: PMC9828425 DOI: 10.1111/ele.14128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 08/11/2022] [Accepted: 09/10/2022] [Indexed: 01/12/2023]
Abstract
Considering the global intensification of aridity in tropical biomes due to climate change, we need to understand what shapes the distribution of drought sensitivity in tropical plants. We conducted a pantropical data synthesis representing 1117 species to test whether xylem-specific hydraulic conductivity (KS ), water potential at leaf turgor loss (ΨTLP ) and water potential at 50% loss of KS (ΨP50 ) varied along climate gradients. The ΨTLP and ΨP50 increased with climatic moisture only for evergreen species, but KS did not. Species with high ΨTLP and ΨP50 values were associated with both dry and wet environments. However, drought-deciduous species showed high ΨTLP and ΨP50 values regardless of water availability, whereas evergreen species only in wet environments. All three traits showed a weak phylogenetic signal and a short half-life. These results suggest strong environmental controls on trait variance, which in turn is modulated by leaf habit along climatic moisture gradients in the tropics.
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Affiliation(s)
- German Vargas G.
- Department of Plant and Microbial BiologyUniversity of MinnesotaSt. PaulMinnesotaUSA,School of Biological SciencesThe University of UtahSalt Lake CityUtahUSA
| | - Norbert Kunert
- Conservation Ecology CenterSmithsonian National Zoo and Conservation Biology InstituteFront RoyalVirginiaUSA,Forest Global Earth ObservatorySmithsonian Tropical Research InstitutePanamaRepublic of Panama,Department of Integrative Biology and Biodiversity Research, Institute of BotanyUniversity of Natural Resources and Life Sciences ViennaViennaAustria
| | - William M. Hammond
- Agronomy Department, Institute of Food and Agricultural SciencesUniversity of FloridaGainesvilleFloridaUSA
| | - Z. Carter Berry
- Department of BiologyWake Forest UniversityWinston‐SalemNorth CarolinaUSA
| | - Leland K. Werden
- Department of Environmental Systems ScienceETH ZürichZürichSwitzerland
| | - Chris M. Smith‐Martin
- Department of Ecology Evolution and Environmental BiologyColumbia UniversityNew YorkNew YorkUSA
| | - Brett T. Wolfe
- School of Renewable Natural ResourcesLouisiana State University Agricultural CenterBaton RougeLouisianaUSA,Smithsonian Tropical Research InstitutePanamaRepublic of Panama
| | - Laura Toro
- Department of Plant and Microbial BiologyUniversity of MinnesotaSt. PaulMinnesotaUSA
| | | | - Jesús N. Pinto‐Ledezma
- Department of Ecology, Evolution and BehaviorUniversity of MinnesotaSt. PaulMinnesotaUSA
| | - Naomi B. Schwartz
- Department of GeographyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - María Uriarte
- Department of Ecology Evolution and Environmental BiologyColumbia UniversityNew YorkNew YorkUSA
| | - Lawren Sack
- Department of Ecology and EvolutionUniversity of California Los AngelesLos AngelesCaliforniaUSA
| | - Kristina J. Anderson‐Teixeira
- Conservation Ecology CenterSmithsonian National Zoo and Conservation Biology InstituteFront RoyalVirginiaUSA,Forest Global Earth ObservatorySmithsonian Tropical Research InstitutePanamaRepublic of Panama
| | - Jennifer S. Powers
- Department of Ecology, Evolution and BehaviorUniversity of MinnesotaSt. PaulMinnesotaUSA
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Lens F, Gleason SM, Bortolami G, Brodersen C, Delzon S, Jansen S. Functional xylem characteristics associated with drought-induced embolism in angiosperms. THE NEW PHYTOLOGIST 2022; 236:2019-2036. [PMID: 36039697 DOI: 10.1111/nph.18447] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Hydraulic failure resulting from drought-induced embolism in the xylem of plants is a key determinant of reduced productivity and mortality. Methods to assess this vulnerability are difficult to achieve at scale, leading to alternative metrics and correlations with more easily measured traits. These efforts have led to the longstanding and pervasive assumed mechanistic link between vessel diameter and vulnerability in angiosperms. However, there are at least two problems with this assumption that requires critical re-evaluation: (1) our current understanding of drought-induced embolism does not provide a mechanistic explanation why increased vessel width should lead to greater vulnerability, and (2) the most recent advancements in nanoscale embolism processes suggest that vessel diameter is not a direct driver. Here, we review data from physiological and comparative wood anatomy studies, highlighting the potential anatomical and physicochemical drivers of embolism formation and spread. We then put forward key knowledge gaps, emphasising what is known, unknown and speculation. A meaningful evaluation of the diameter-vulnerability link will require a better mechanistic understanding of the biophysical processes at the nanoscale level that determine embolism formation and spread, which will in turn lead to more accurate predictions of how water transport in plants is affected by drought.
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Affiliation(s)
- Frederic Lens
- Naturalis Biodiversity Center, PO Box 9517, 2300 RA, Leiden, the Netherlands
- Leiden University, Institute of Biology Leiden, Plant Sciences, Sylviusweg 72, 2333 BE, Leiden, the Netherlands
| | - Sean M Gleason
- Water Management and Systems Research Unit, United States Department of Agriculture, Agricultural Research Service, Fort Collins, CO, 80526, USA
| | - Giovanni Bortolami
- Naturalis Biodiversity Center, PO Box 9517, 2300 RA, Leiden, the Netherlands
| | - Craig Brodersen
- School of the Environment, Yale University, New Haven, CT, 06511, USA
| | - Sylvain Delzon
- University of Bordeaux, INRAE, BIOGECO, 33615, Pessac, France
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, D-89081, Ulm, Germany
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34
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Zlobin IE, Kartashov AV, Ivanov YV, Ivanova AI, Kuznetsov VV. Stem notching decreases stem hydraulic conductance but does not influence drought impacts and post-drought recovery in Scots pine and Norway spruce. PHYSIOLOGIA PLANTARUM 2022; 174:e13813. [PMID: 36326172 DOI: 10.1111/ppl.13813] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 10/24/2022] [Accepted: 10/26/2022] [Indexed: 06/16/2023]
Abstract
The tight connection between the deterioration of xylem function and plant mortality under drought is well recognized. However, a lack of mechanistic understanding of how substantial conductivity loss influences plant performance under drought and during post-drought recovery hinders our ability to model tree responses to drought stress. We artificially induced a loss of 50% of xylem conducting area in Scots pine and Norway spruce saplings by stem notching and investigated plant performance under drought and during post-drought recovery. Plant mortality, xylem hydraulic conductivity, leaf water status and stomatal conductance were measured. We observed no preferential mortality of top plant parts (above the notches) compared to basal plant parts (below the notches), and no consistent trend in hydraulic conductivity loss was observed between top and basal parts of dying plants. Stem hydraulic conductivity, water status of the needles and stomatal conductance changed similarly between the top and basal parts during drought and post-drought recovery, which indicated the substantial hydraulic overcapacity of the stems. The recovery of stomatal conductance demonstrated prominent hysteresis due to non-hydraulic stomatal limitations. The results obtained are highly important for modelling the influence of plant hydraulic impairment on plant performance under drought and during post-drought recovery.
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Affiliation(s)
- Ilya E Zlobin
- K.A. Timiryazev Institute of Plant Physiology RAS, Moscow, Russia
| | | | - Yury V Ivanov
- K.A. Timiryazev Institute of Plant Physiology RAS, Moscow, Russia
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35
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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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36
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Peng G, Geng H, Li Y, Ren Z, Peng J, Cao L, Pereira L, Tyree MT, Yang D. The theory behind vessel length determination using gas flow rates and comparison between two pneumatic methods based on seven woody species. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:5612-5624. [PMID: 35552690 DOI: 10.1093/jxb/erac206] [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: 12/10/2021] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
In plants, xylem vessel length is important for long-distance water transport; however, the currently used methods for vessel length measurement are inconvenient and time-consuming. The recently developed semi-automated Pneumatron is a device based on the pneumatic theory that is similar to the air-injection method, and can rapidly estimate vessel length. Mean vessel length was compared between the Pneumatron and the air-injection method in seven woody species with a wide range of vessel lengths (2.3-78.7 cm). The results were consistent between the two methods, regardless of whether the same or different samples were used. The theory underlying the gas flow in vessels was improved and expanded, and compared to that underlying the water flow in order to better understand the pneumatic processes within a stem sample. Moreover, a new and simple equation for gas flow in vessels was derived based on the molar gas flow (mol s-1) rather than volume flow, because the former remains constant with distance throughout the stem axis. We strongly recommend using the Pneumatron in future studies owing to its low cost, convenience, rapidity, and simple operation. However, a number of potential issues need to be considered to avoid artifacts during measurements.
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Affiliation(s)
- Guoquan Peng
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Hongru Geng
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Yaxin Li
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Zhiyang Ren
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Juan Peng
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Lei Cao
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Luciano Pereira
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Melvin T Tyree
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Dongmei Yang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
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37
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Oliveira LA, Cardoso AA, Andrade MT, Pereira TS, Araújo WL, Santos GA, Damatta FM, Martins SCV. Exploring leaf hydraulic traits to predict drought tolerance of Eucalyptus clones. TREE PHYSIOLOGY 2022; 42:1750-1761. [PMID: 35388901 DOI: 10.1093/treephys/tpac040] [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: 10/07/2021] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Ongoing changes in climate, and the consequent mortality of natural and cultivated forests across the globe, highlight the urgent need to understand the plant traits associated with greater tolerance to drought. Here, we aimed at assessing key foliar traits, with a focus on the hydraulic component, that could confer a differential ability to tolerate drought in three commercial hybrids of the most important Eucalyptus species utilized in tropical silviculture: E. urophyla, E. grandis and E. camaldulensis. All genotypes exhibited similar water potential when the 90% stomatal closure (Ψgs90) occurs with Ψgs90 always preceding the start of embolism events. The drought-tolerant hybrid showed a higher leaf resistance to embolism, but the leaf hydraulic efficiency was similar among all genotypes. Other traits presented by the drought-tolerant hybrid were a higher cell wall reinforcement, lower value of osmotic potential at full turgor and greater bulk modulus of elasticity. We also identified that the leaf capacitance after the turgor loss, the ratio between cell wall thickness (t) and lumen breadth (b) ratio (t/b)3, and the minimal conductance might be good proxies for screening drought-tolerant Eucalyptus genotypes. Our findings suggest that xylem resistance to embolism can be an important component of drought tolerance in Eucalyptus in addition to other traits aimed at delaying the development of high tensions in the xylem. Highlight Drought tolerance in tropical Eucalyptus hybrids encompasses a high leaf resistance to embolism and a suite of traits aimed at delaying the development of high tensions in the xylem.
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Affiliation(s)
- Leonardo A Oliveira
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Amanda A Cardoso
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Moab T Andrade
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Talitha S Pereira
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Wagner L Araújo
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Gleison A Santos
- Departmento de Engenharia Florestal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Fábio M Damatta
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Samuel C V Martins
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
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38
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Álvarez-Maldini C, Acevedo M, Estay D, Aros F, Dumroese RK, Sandoval S, Pinto M. Examining physiological, water relations, and hydraulic vulnerability traits to determine anisohydric and isohydric behavior in almond ( Prunus dulcis) cultivars: Implications for selecting agronomic cultivars under changing climate. FRONTIERS IN PLANT SCIENCE 2022; 13:974050. [PMID: 36092408 PMCID: PMC9453546 DOI: 10.3389/fpls.2022.974050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/04/2022] [Indexed: 06/15/2023]
Abstract
The search for drought tolerant species or cultivars is important to address water scarcity caused by climate change in Mediterranean regions. The anisohydric-isohydric behavior concept has been widely used to describe stomatal regulation during drought, simply in terms of variation of minimal water potential (Ψmin) in relation to pre-dawn water potential (Ψpd). However, its simplicity has sometimes failed to deliver consistent results in describing a complex behavior that results from the coordination of several plant functional traits. While Prunus dulcis (almond) is known as a drought tolerant species, little information is available regarding consistent metrics to discriminate among cultivars or the mechanisms underlying drought tolerance in almond. Here we show a sequence of plant stomatal, hydraulic, and wilting responses to drought in almonds, and the main differences between anisohydric and isohydric cultivars. In a pot desiccation experiment we observed that stomatal closure in P. dulcis is not driven by loss in turgor or onset of xylem cavitation, but instead, occurs early in response to decreasing Ψmin that could be related to the protection of the integrity of the hydraulic system, independently of cultivar. Also, we report that anisohydric cultivars of P. dulcis are characterized by maximum stomatal conductance, lower water potentials for stomatal closure and turgor loss, and lower vulnerability to xylem cavitation, which are traits that correlated with metrics to discriminate anisohydric and isohydric behavior. Our results demonstrate that P. dulcis presents a strategy to avoid cavitation by closing stomata during the early stages of drought. Future research should also focus on below-ground hydraulic traits, which could trigger stomatal closure in almond.
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Affiliation(s)
- Carolina Álvarez-Maldini
- Instituto Ciencias Agroalimentarias Animales y Ambientales (ICA3), Campus Colchagua, Universidad de O′Higgins, San Fernando, Chile
| | - Manuel Acevedo
- Centro Tecnológico de la Planta Forestal, Instituto Forestal, Sede Biobío, San Pedro de la Paz, Chile
| | - Daniela Estay
- Instituto Ciencias Agroalimentarias Animales y Ambientales (ICA3), Campus Colchagua, Universidad de O′Higgins, San Fernando, Chile
| | - Fabián Aros
- Instituto Ciencias Agroalimentarias Animales y Ambientales (ICA3), Campus Colchagua, Universidad de O′Higgins, San Fernando, Chile
| | - R. Kasten Dumroese
- United States Department of Agriculture Forest Service, Rocky Mountain Research Station, Moscow, ID, United States
| | - Simón Sandoval
- Laboratorio de Análisis y Modelamiento de Geoinformación, Departamento de Manejo de Bosques y Medio Ambiente, Facultad de Ciencias Forestales, Universidad de Concepción, Concepción, Chile
| | - Manuel Pinto
- Instituto Ciencias Agroalimentarias Animales y Ambientales (ICA3), Campus Colchagua, Universidad de O′Higgins, San Fernando, Chile
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39
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Jiang (蒋国凤) GF, Li (李溯源) SY, Li (李艺蝉) YC, Roddy AB. Coordination of hydraulic thresholds across roots, stems, and leaves of two co-occurring mangrove species. PLANT PHYSIOLOGY 2022; 189:2159-2174. [PMID: 35640109 PMCID: PMC9342987 DOI: 10.1093/plphys/kiac240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/09/2022] [Indexed: 05/30/2023]
Abstract
Mangroves are frequently inundated with saline water and have evolved different anatomical and physiological mechanisms to filter and, in some species, excrete excess salt from the water they take up. Because salts impose osmotic stress, interspecific differences in salt tolerance and salt management strategy may influence physiological responses to drought throughout the entire plant hydraulic pathway, from roots to leaves. Here, we characterized embolism vulnerability simultaneously in leaves, stems, and roots of seedlings of two mangrove species (Avicennia marina and Bruguiera gymnorrhiza) along with turgor-loss points in roots and leaves and xylem anatomical traits. In both species, the water potentials causing 50% of total embolism were less negative in roots and leaves than they were in stems, but the water potentials causing incipient embolism (5%) were similar in roots, stems, and leaves. Stomatal closure in leaves and turgor loss in both leaves and roots occurred at water potentials only slightly less negative than the water potentials causing 5% of total embolism. Xylem anatomical traits were unrelated to vulnerability to embolism. Vulnerability segmentation may be important in limiting embolism spread into stems from more vulnerable roots and leaves. Interspecific differences in salt tolerance affected hydraulic traits from roots to leaves: the salt-secretor A. marina lost turgor at more negative water potentials and had more embolism-resistant xylem than the salt-excluder B. gymnorrhiza. Characterizing physiological thresholds of roots may help to explain recent mangrove mortality after drought and extended saltwater inundation.
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Affiliation(s)
| | - Su-Yuan Li (李溯源)
- Guangxi Key Laboratory of Forest Ecology and Conservation, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry, Guangxi University, Nanning 530004, China
| | - Yi-Chan Li (李艺蝉)
- Guangxi Key Laboratory of Forest Ecology and Conservation, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry, Guangxi University, Nanning 530004, China
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Cardoso AA, Kane CN, Rimer IM, McAdam SAM. Seeing is believing: what visualising bubbles in the xylem has revealed about plant hydraulic function. FUNCTIONAL PLANT BIOLOGY : FPB 2022; 49:759-772. [PMID: 35718950 DOI: 10.1071/fp21326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 05/29/2022] [Indexed: 06/15/2023]
Abstract
Maintaining water transport in the xylem is critical for vascular plants to grow and survive. The drought-induced accumulation of embolism, when gas enters xylem conduits, causes declines in hydraulic conductance (K ) and is ultimately lethal. Several methods can be used to estimate the degree of embolism in xylem, from measuring K in tissues to directly visualising embolism in conduits. One method allowing a direct quantification of embolised xylem area is the optical vulnerability (OV) technique. This method has been used across different organs and has a high spatial and temporal resolution. Here, we review studies using the OV technique, discuss the main advantages and disadvantages of this method, and summarise key advances arising from its use. Vulnerability curves generated by the OV method are regularly comparable to other methods, including the centrifuge and X-ray microtomography. A major advantage of the OV technique over other methods is that it can be simultaneously used to determine in situ embolism formation in leaves, stems and roots, in species spanning the phylogeny of land plants. The OV method has been used to experimentally investigate the spreading of embolism through xylem networks, associate embolism with downstream tissue death, and observe embolism formation in the field.
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Affiliation(s)
- Amanda A Cardoso
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Cade N Kane
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - Ian M Rimer
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - Scott A M McAdam
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
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41
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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: 18] [Impact Index Per Article: 9.0] [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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42
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Song J, Trueba S, Yin XH, Cao KF, Brodribb TJ, Hao GY. Hydraulic vulnerability segmentation in compound-leaved trees: Evidence from an embolism visualization technique. PLANT PHYSIOLOGY 2022; 189:204-214. [PMID: 35099552 PMCID: PMC9070814 DOI: 10.1093/plphys/kiac034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/27/2021] [Indexed: 05/11/2023]
Abstract
The hydraulic vulnerability segmentation (HVS) hypothesis implies the existence of differences in embolism resistance between plant organs along the xylem pathway and has been suggested as an adaptation allowing the differential preservation of more resource-rich tissues during drought stress. Compound leaves in trees are considered a low-cost means of increasing leaf area and may thus be expected to show evidence of strong HVS, given the tendency of compound-leaved tree species to shed their leaf units during drought. However, the existence and role of HVS in compound-leaved tree species during drought remain uncertain. We used an optical visualization technique to estimate embolism occurrence in stems, petioles, and leaflets of shoots in two compound-leaved tree species, Manchurian ash (Fraxinus mandshurica) and Manchurian walnut (Juglans mandshurica). We found higher (less negative) water potentials corresponding to 50% loss of conductivity (P50) in leaflets and petioles than in stems in both species. Overall, we observed a consistent pattern of stem > petiole > leaflet in terms of xylem resistance to embolism and hydraulic safety margins (i.e. the difference between mid-day water potential and P50). The coordinated variation in embolism vulnerability between organs suggests that during drought conditions, trees benefit from early embolism and subsequent shedding of more expendable organs such as leaflets and petioles, as this provides a degree of protection to the integrity of the hydraulic system of the more carbon costly stems. Our results highlight the importance of HVS as an adaptive mechanism of compound-leaved trees to withstand drought stress.
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Affiliation(s)
- Jia Song
- CAS Key Laboratory of Forest Ecology and Management & Key Laboratory of Terrestrial Ecosystem Carbon Neutrality Liaoning Province, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning, China
- School of Environmental and Geographical Science, Shanghai Normal University, Shanghai 200234, China
- Yangtze River Delta National Observatory of Wetland Ecosystem, Shanghai Normal University, Shanghai 200234, China
| | - Santiago Trueba
- University of Bordeaux, INRAE, BIOGECO, 33615 Pessac, France
| | - Xiao-Han Yin
- CAS Key Laboratory of Forest Ecology and Management & Key Laboratory of Terrestrial Ecosystem Carbon Neutrality Liaoning Province, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning, China
| | - Kun-Fang Cao
- Plant Ecophysiology and Evolution Group, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, and College of Forestry, Guangxi University, Nanning, Guangxi 530004, China
| | - Timothy J Brodribb
- Biological Sciences, School of Natural Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
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Avila RT, Guan X, Kane CN, Cardoso AA, Batz TA, DaMatta FM, Jansen S, McAdam SAM. Xylem embolism spread is largely prevented by interconduit pit membranes until the majority of conduits are gas-filled. PLANT, CELL & ENVIRONMENT 2022; 45:1204-1215. [PMID: 34984700 DOI: 10.1111/pce.14253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 11/29/2021] [Accepted: 12/11/2021] [Indexed: 06/14/2023]
Abstract
Xylem embolism resistance varies across species influencing drought tolerance, yet little is known about the determinants of the embolism resistance of an individual conduit. Here we conducted an experiment using the optical vulnerability method to test whether individual conduits have a specific water potential threshold for embolism formation and whether pre-existing embolism in neighbouring conduits alters this threshold. Observations were made on a diverse sample of angiosperm and conifer species through a cycle of dehydration, rehydration and subsequent dehydration to death. Upon rehydration after the formation of embolism, no refilling was observed. When little pre-existing embolism was present, xylem conduits had a conserved, individual embolism-resistance threshold that varied across the population of conduits. The consequence of a variable conduit-specific embolism threshold is that a small degree of pre-existing embolism in the xylem results in apparently more resistant xylem in subsequent dehydrations, particularly in angiosperms with vessels. While our results suggest that pit membranes separating xylem conduits are critical for maintaining a conserved individual conduit threshold for embolism when little pre-existing embolism is present, as the percentage of embolized conduits increases, gas movement, local pressure differences and connectivity between conduits increasingly contribute to embolism spread.
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Affiliation(s)
- Rodrigo T Avila
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, Indiana, USA
| | - Xinyi Guan
- Institute of Systematic Botany and Ecology, Faculty of Natural Sciences, Ulm University, Ulm, Baden-Württemberg, Germany
| | - Cade N Kane
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, Indiana, USA
| | - Amanda A Cardoso
- Instituto de Ciências da Natureza, Universidade Federal de Alfenas, Alfenas, Brazil
| | - Timothy A Batz
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, Indiana, USA
| | - Fábio M DaMatta
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Faculty of Natural Sciences, Ulm University, Ulm, Baden-Württemberg, Germany
| | - Scott A M McAdam
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, Indiana, USA
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44
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Guillemot J, Martin-StPaul NK, Bulascoschi L, Poorter L, Morin X, Pinho BX, le Maire G, R L Bittencourt P, Oliveira RS, Bongers F, Brouwer R, Pereira L, Gonzalez Melo GA, Boonman CCF, Brown KA, Cerabolini BEL, Niinemets Ü, Onoda Y, Schneider JV, Sheremetiev S, Brancalion PHS. Small and slow is safe: On the drought tolerance of tropical tree species. GLOBAL CHANGE BIOLOGY 2022; 28:2622-2638. [PMID: 35007364 DOI: 10.1111/gcb.16082] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/09/2021] [Accepted: 12/09/2021] [Indexed: 06/14/2023]
Abstract
Understanding how evolutionary history and the coordination between trait trade-off axes shape the drought tolerance of trees is crucial to predict forest dynamics under climate change. Here, we compiled traits related to drought tolerance and the fast-slow and stature-recruitment trade-off axes in 601 tropical woody species to explore their covariations and phylogenetic signals. We found that xylem resistance to embolism (P50) determines the risk of hydraulic failure, while the functional significance of leaf turgor loss point (TLP) relies on its coordination with water use strategies. P50 and TLP exhibit weak phylogenetic signals and substantial variation within genera. TLP is closely associated with the fast-slow trait axis: slow species maintain leaf functioning under higher water stress. P50 is associated with both the fast-slow and stature-recruitment trait axes: slow and small species exhibit more resistant xylem. Lower leaf phosphorus concentration is associated with more resistant xylem, which suggests a (nutrient and drought) stress-tolerance syndrome in the tropics. Overall, our results imply that (1) drought tolerance is under strong selective pressure in tropical forests, and TLP and P50 result from the repeated evolutionary adaptation of closely related taxa, and (2) drought tolerance is coordinated with the ecological strategies governing tropical forest demography. These findings provide a physiological basis to interpret the drought-induced shift toward slow-growing, smaller, denser-wooded trees observed in the tropics, with implications for forest restoration programmes.
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Affiliation(s)
- Joannès Guillemot
- CIRAD, UMR Eco&Sols, Piracicaba, São Paulo, Brazil
- Eco&Sols, Univ. Montpellier, CIRAD, INRAe, Institut Agro, IRD, Montpellier, France
- Department of Forest Sciences, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
| | | | - Leticia Bulascoschi
- Department of Forest Sciences, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
| | - Lourens Poorter
- Forest Ecology and Forest Management Group, Wageningen University, Wageningen, The Netherlands
| | - Xavier Morin
- CEFE, CNRS, Univ. Montpellier, EPHE, IRD, Univ. Paul Valéry Montpellier 3, Montpellier, France
| | - Bruno X Pinho
- AMAP, Univ Montpellier, INRAe, CIRAD, CNRS, IRD, Montpellier, France
- Departamento de Botânica, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Guerric le Maire
- CIRAD, UMR Eco&Sols, Piracicaba, São Paulo, Brazil
- Eco&Sols, Univ. Montpellier, CIRAD, INRAe, Institut Agro, IRD, Montpellier, France
| | | | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| | - Frans Bongers
- Forest Ecology and Forest Management Group, Wageningen University, Wageningen, The Netherlands
| | - Rens Brouwer
- Forest Ecology and Forest Management Group, Wageningen University, Wageningen, The Netherlands
| | - Luciano Pereira
- Department of Plant Biology, Institute of Biology, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
| | | | - Coline C F Boonman
- Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research, Radboud University, Nijmegen, The Netherlands
| | - Kerry A Brown
- Department of Geography, Geology and the Environment, Kingston University London, Kingston Upon Thames, UK
| | - Bruno E L Cerabolini
- Department of Biotechnologies and Life Sciences (DBSV), University of Insubria, Varese, Italy
| | - Ülo Niinemets
- Estonian University of Life Sciences, Tartu, Estonia
| | - Yusuke Onoda
- Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Julio V Schneider
- Department of Botany and Molecular Evolution, Senckenberg Research Institute and Natural History Museum Frankfurt, Frankfurt, Germany
- Senckenberg Research Institute and Natural History Museum Frankfurt, Frankfurt, Germany
| | | | - Pedro H S Brancalion
- Department of Forest Sciences, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
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45
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Benson MC, Miniat CF, Oishi AC, Denham SO, Domec JC, Johnson DM, Missik JE, Phillips RP, Wood JD, Novick KA. The xylem of anisohydric Quercus alba L. is more vulnerable to embolism than isohydric codominants. PLANT, CELL & ENVIRONMENT 2022; 45:329-346. [PMID: 34902165 DOI: 10.1111/pce.14244] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/01/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
The coordination of plant leaf water potential (ΨL ) regulation and xylem vulnerability to embolism is fundamental for understanding the tradeoffs between carbon uptake and risk of hydraulic damage. There is a general consensus that trees with vulnerable xylem more conservatively regulate ΨL than plants with resistant xylem. We evaluated if this paradigm applied to three important eastern US temperate tree species, Quercus alba L., Acer saccharum Marsh. and Liriodendron tulipifera L., by synthesizing 1600 ΨL observations, 122 xylem embolism curves and xylem anatomical measurements across 10 forests spanning pronounced hydroclimatological gradients and ages. We found that, unexpectedly, the species with the most vulnerable xylem (Q. alba) regulated ΨL less strictly than the other species. This relationship was found across all sites, such that coordination among traits was largely unaffected by climate and stand age. Quercus species are perceived to be among the most drought tolerant temperate US forest species; however, our results suggest their relatively loose ΨL regulation in response to hydrologic stress occurs with a substantial hydraulic cost that may expose them to novel risks in a more drought-prone future.
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Affiliation(s)
- Michael C Benson
- O'Neill School of Public and Environmental Affairs, Indiana University Bloomington, Bloomington, Indiana, USA
| | - Chelcy F Miniat
- USDA Forest Service, Southern Research Station, Coweeta Hydrologic Laboratory, Otto, North Carolina, USA
| | - Andrew C Oishi
- USDA Forest Service, Southern Research Station, Coweeta Hydrologic Laboratory, Otto, North Carolina, USA
| | - Sander O Denham
- O'Neill School of Public and Environmental Affairs, Indiana University Bloomington, Bloomington, Indiana, USA
| | - Jean-Christophe Domec
- Bordeaux Sciences Agro, INRA UMR 1391 ISPA, Gradignan, France
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | - Daniel M Johnson
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, Georgia, USA
| | - Justine E Missik
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Richard P Phillips
- Department of Biology, Indiana University Bloomington, Bloomington, Indiana, USA
| | - Jeffrey D Wood
- University of Missouri, School of Natural Resources, Columbia, Missouri, USA
| | - Kimberly A Novick
- O'Neill School of Public and Environmental Affairs, Indiana University Bloomington, Bloomington, Indiana, USA
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46
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Hydraulic Function Analysis of Conifer Xylem Based on a Model Incorporating Tracheids, Bordered Pits, and Cross-Field Pits. FORESTS 2022. [DOI: 10.3390/f13020171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Wood has a highly complex and anisotropic structure. Its xylem characteristics are key in determining the hydraulic properties of plants to transport water efficiently and safely, as well as the permeability in the process of wood impregnation modification. Previous studies on the relationship between the xylem structure and hydraulic conductivity of conifer have mainly focused on tracheids and bordered pits, with only a few focusing on the conduction model of cross-field pits which connect tracheids and rays. This study takes the xylem structure of conifer as an example, drawing an analogy between water flow under tension and electric current, and extends the model to the tissue scale, including cross-field pits by establishing isometric scaling. The structure parameters were collected by scanning electron microscopy and transmission electron microscopy. The improved model can quantify the important hydraulic functional characteristics of xylem only by measuring the more easily obtained tracheid section size. Then, this model was applied to quantify the relationship between the xylem anatomical structure and hydraulic properties in the pine (Pinus sylvestris L. var. mongholica Litv.) and the spruce (Picea koraiensis Nakai), and also to evaluate the effects of the number and size of cross-field pits on xylem conduction. The results showed that the growth ring conduction value of the pine was more than twice that of the spruce for the two tree species with similar growth widths in this study. The tracheid wall resistance of the pine reflected the result of the interaction of the size and number of cross-field pits, in comparison, the wall resistance of the spruce was more sensitive to the number of cross-field pits. Finally, the calculation output of the new model was cross-validated with the literature, which verified the accuracy and effectiveness of the model. This study provides an effective and complete solution for xylem conductivity measurement and the study of wood ecophysiological diversity and processing.
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47
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Lauriks F, Salomón RL, De Roo L, Goossens W, Leroux O, Steppe K. Limited plasticity of anatomical and hydraulic traits in aspen trees under elevated CO2 and seasonal drought. PLANT PHYSIOLOGY 2022; 188:268-284. [PMID: 34718790 PMCID: PMC8774844 DOI: 10.1093/plphys/kiab497] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
The timing of abiotic stress elicitors on wood formation largely affects xylem traits that determine xylem efficiency and vulnerability. Nonetheless, seasonal variability of elevated CO2 (eCO2) effects on tree functioning under drought remains largely unknown. To address this knowledge gap, 1-year-old aspen (Populus tremula L.) trees were grown under ambient (±445 ppm) and elevated (±700 ppm) CO2 and exposed to an early (spring/summer 2019) or late (summer/autumn 2018) season drought event. Stomatal conductance and stem shrinkage were monitored in vivo as xylem water potential decreased. Additional trees were harvested for characterization of wood anatomical traits and to determine vulnerability and desorption curves via bench dehydration. The abundance of narrow vessels decreased under eCO2 only during the early season. At this time, xylem vulnerability to embolism formation and hydraulic capacitance during severe drought increased under eCO2. Contrastingly, stomatal closure was delayed during the late season, while hydraulic vulnerability and capacitance remained unaffected under eCO2. Independently of the CO2 treatment, elastic, and inelastic water pools depleted simultaneously after 50% of complete stomatal closure. Our results suggest that the effect of eCO2 on drought physiology and wood traits are small and variable during the growing season and question a sequential capacitive water release from elastic and inelastic pools as drought proceeds.
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Affiliation(s)
- Fran Lauriks
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Roberto Luis Salomón
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
- Grupo de Investigación Sistemas Naturales e Historia Forestal, Universidad Politécnica de Madrid, Madrid 28040, Spain
| | - Linus De Roo
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Willem Goossens
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Olivier Leroux
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
- Department of Biology, Faculty of Sciences, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Kathy Steppe
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
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48
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Johnson KM, Lucani C, Brodribb TJ. In vivo monitoring of drought-induced embolism in Callitris rhomboidea trees reveals wide variation in branchlet vulnerability and high resistance to tissue death. THE NEW PHYTOLOGIST 2022; 233:207-218. [PMID: 34625973 DOI: 10.1111/nph.17786] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
Damage to the plant water transport system through xylem cavitation is known to be a driver of plant death in drought conditions. However, a lack of techniques to continuously monitor xylem embolism in whole plants in vivo has hampered our ability to investigate both how this damage propagates and the possible mechanistic link between xylem damage and tissue death. Using optical and fluorescence sensors, we monitored drought-induced xylem embolism accumulation and photosynthetic damage in vivo throughout the canopy of a drought-resistant conifer, Callitris rhomboidea, during drought treatments of c. 1 month duration. We show that drought-induced damage to the xylem can be monitored in vivo in whole trees during extended periods of water stress. Under these conditions, vulnerability of the xylem to cavitation varied widely among branchlets, with photosynthetic damage only recorded once > 90% of the xylem was cavitated. The variation in branchlet vulnerability has important implications for understanding how trees like C. rhomboidea survive drought, and the high resistance of branchlets to tissue damage points to runaway cavitation as a likely driver of tissue death in C. rhomboidea branch tips.
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Affiliation(s)
- Kate M Johnson
- Discipline of Biological Sciences, School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS, 7001, Australia
| | - Christopher Lucani
- Discipline of Biological Sciences, School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS, 7001, Australia
| | - Timothy J Brodribb
- Discipline of Biological Sciences, School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS, 7001, Australia
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49
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Lübbe T, Lamarque LJ, Delzon S, Torres Ruiz JM, Burlett R, Leuschner C, Schuldt B. High variation in hydraulic efficiency but not xylem safety between roots and branches in four temperate broad‐leaved tree species. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13975] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Torben Lübbe
- Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen Goettingen Germany
| | - Laurent J. Lamarque
- Département des Sciences de l'environnement Université du Québec à Trois‐Rivières Trois‐Rivières QC Canada
- University of Bordeaux INRAE BIOGECO Pessac France
| | | | | | | | - Christoph Leuschner
- Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen Goettingen Germany
| | - Bernhard Schuldt
- Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen Goettingen Germany
- Julius‐von‐Sachs‐Institute of Biological Sciences, Ecophysiology and Vegetation Ecology University of Würzburg Würzburg Germany
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50
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Mayr S. Relevance of time and spatial scales in plant hydraulics. TREE PHYSIOLOGY 2021; 41:1781-1784. [PMID: 34296269 PMCID: PMC8498925 DOI: 10.1093/treephys/tpab093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 07/16/2021] [Indexed: 05/11/2023]
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