Addressing controversies in the xylem embolism resistance–vessel diameter relationship

New Phytologist, Journal Year: 2023, Volume and Issue: 238(1), P. 283 - 296

Published: Jan. 13, 2023

Summary Although xylem embolism is a key process during drought‐induced tree mortality, its relationship to wood anatomy remains debated. While the functional link between bordered pits and resistance known, there no direct, mechanistic explanation for traditional assumption that wider vessels are more vulnerable than narrow ones. We used data from 20 temperate broad‐leaved species study inter‐ intraspecific of water potential at 50% loss conductivity ( P 50 ) with hydraulically weighted vessel diameter D h tested pit membrane thickness T PM specific K s on level. Embolism‐resistant had thick membranes vessels. was weakly associated , – remained highly significant after accounting . The interspecific pattern mirrored by but evidence an relationship. Our results provide robust across our species. As cause inconsistencies in published relationships, analysis suggests differences range trait values covered, level aggregation (species, or sample level) studied.

Language: Английский

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Tree crown defoliation in forest monitoring: concepts, findings, and new perspectives for a physiological approach in the face of climate change

Forestry An International Journal of Forest Research, Journal Year: 2024, Volume and Issue: 97(2), P. 194 - 212

Published: Jan. 5, 2024

Abstract Recurrent climate-driven disturbances impact on the health of European forests that reacted with increased tree dieback and mortality over course last four decades. There is therefore large interest in predicting understanding fate survival under climate change. Forest conditions are monitored within pan-European ICP Forests programme (UN-ECE International Co-operative Programme Assessment Monitoring Air Pollution Effects Forests) since 1980s, crown defoliation being most widely used parameter. Defoliation not a cause-specific indicator vitality, there need to connect levels physiological functioning trees. The responses connected species-specific concern, among others, water relations, photosynthesis carbon metabolism, growth, mineral nutrients leaves. indicators measure variables forest monitoring programs must be easy apply field current state-of-the-art technologies, replicable, inexpensive, time efficient regulated by ad hoc protocols. ultimate purpose provide data feed process-based models predict threats due This study reviews problems perspectives realization systematic assessment proposes set suitable for future application programs.

Language: Английский

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Divergence of vessel diameter explains interspecific variation in hydraulic safety to salinity in the Sundarbans mangrove ecosystem

Functional Ecology, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 28, 2025

Abstract Despite their crucial role in providing ecosystem services and livelihood support 124 countries, mangroves are facing challenges from warming, altered seasonal precipitation sea level rise (SLR) the face of climate change. Variation intra‐ interspecific hydraulic traits related xylem anatomy may allow trees to adapt changing environmental conditions, yet little is known about adaptive plasticity mangroves. We examined (i) trait variation across three (low, medium high) salinity zones widespread mangrove species ( Exocecaria agallocha , Xylocarpus moluccensis Heritiera fomes ) with distinct shade tolerance characteristics Bangladesh Sundarbans, (ii) associations traits, (iii) habitat (regulator, resource forest structure) effects on vessel diameter due its strong influence conductivity variation. Although potential (K P leaf‐specific L showed species‐specific variation, a notably greater was found low‐salinity zone (LSZ), which had lower wall reinforcement (t/b) 2 . Xylem exhibited mostly phylogenetic signals, whereas pairwise relationships between were phylogenetically independent. The study characteristics, where D strongly K Furthermore, weak trade‐off efficiency safety. A percentage smaller diameters light‐demanding E. indicates safety against cavitation under stressful conditions than shade‐tolerant H. followed by X. place broad bounds combined salinity, nutrient availability tree size modulate diameter, leads contrasting terms suggests an important adaptation distribution. results also provide insight into salinity‐induced growth reduction mortality Read free Plain Language Summary for this article Journal blog.

Language: Английский

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The Response of Beech (Fagus sylvatica L.) Populations to Climate in the Easternmost Sites of Its European Distribution

Plants, Journal Year: 2022, Volume and Issue: 11(23), P. 3310 - 3310

Published: Nov. 30, 2022

In the context of forecasted climate change scenarios, growth forest tree species at their distribution margin is crucial to adapt current management strategies. Analyses beech (Fagus sylvatica L.) have shown high plasticity, but easternmost populations been rarely studied. To describe response marginal population in far east sites its distribution, we first compiled new ring width chronologies. Then analyzed climate-growth relationships for three Republic Moldova. We observed a relatively rate compared core sites. Our analyses further revealed distinct and significant all climatic variables, assessing time relationship between vapor pressure deficit (VPD) which described how plant responds drought. These results highlight that accumulated water an essential limiting factor this region. conclusion, drought-limited, sensitivity VPD will need be considered future studies update other economic ecologically important species.

Language: Английский

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The root of the problem: diverse vulnerability to xylem cavitation found within the root system of wheat plants

New Phytologist, Journal Year: 2023, Volume and Issue: 239(4), P. 1239 - 1252

Published: June 12, 2023

The propagation of xylem embolism throughout the root systems drought-affected plants remains largely unknown, despite this process being comparatively well characterized in aboveground tissues. We used optical and X-ray imaging to capture across intact bread wheat (Triticum aestivum L. 'Krichauff') subjected drying. Patterns vulnerability cavitation were examined investigate whether may vary based on size placement entire system. Individual exhibited similar mean whole system vulnerabilities but showed enormous 6 MPa variation within their component roots (c. 50 per plant). Xylem typically initiated smallest, peripheral parts moved inwards upwards towards collar last, although trend was highly variable. This pattern spread likely results sacrifice replaceable small while preserving function larger, more costly central roots. A distinct embolism-spread belowground has implications for how we understand impact drought as a critical interface between plant soil.

Language: Английский

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Optimal balancing of xylem efficiency and safety explains plant vulnerability to drought

Ecology Letters, Journal Year: 2023, Volume and Issue: 26(9), P. 1485 - 1496

Published: June 17, 2023

In vast areas of the world, forests and vegetation are water limited plant survival depends on ability to avoid catastrophic hydraulic failure. Therefore, it is remarkable that plants take risks by operating at potentials (ψ) induce partial failure conduits (xylem). Here we present an eco-evolutionary optimality principle for xylem conduit design explains this phenomenon based hypothesis conductive efficiency safety optimally co-adapted environment. The model relationship between tolerance negative potential (ψ50 ) environmentally dependent minimum ψ (ψmin across a large number species, along pathway within individuals two species studied. wider margin in gymnosperms compared angiosperms can be explained as adaptation higher susceptibility accumulation embolism. provides novel optimality-based perspective efficiency.

Language: Английский

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Long-term changes in radial growth of seven tree species in the mixed broadleaf-Korean pine forest in Northeast China: Are deciduous trees favored by climate change?

Journal of Forestry Research, Journal Year: 2024, Volume and Issue: 35(1)

Published: April 6, 2024

Language: Английский

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Gradients in embolism resistance within stems driven by secondary growth in herbs

Plant Cell & Environment, Journal Year: 2024, Volume and Issue: 47(8), P. 2986 - 2998

Published: April 21, 2024

Abstract The stems of some herbaceous species can undergo basal secondary growth, leading to a continuum in the degree woodiness along stem. Whether formation growth stem base results differences embolism resistance between and upper portions is unknown. We assessed leaves simultaneously within same individuals two divergent that mature bases. were Solanum lycopersicum (tomato) Senecio minimus (fireweed). Basal plants both displayed advanced greater than This also resulted significant vulnerability segmentation species. Greater woodier was found alongside decreases pith‐to‐xylem ratio, increases proportion xylem, lignin content. show there be considerable variation across herbs this linked present. A gradient could an adaptation ensure reproduction or resprouting during episodes drought late lifecycle.

Language: Английский

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A Solanum lycopersicum polyamine oxidase contributes to the control of plant growth, xylem differentiation, and drought stress tolerance

The Plant Journal, Journal Year: 2024, Volume and Issue: 119(2), P. 960 - 981

Published: May 18, 2024

Polyamines are involved in several plant physiological processes. In Arabidopsis thaliana, five FAD-dependent polyamine oxidases (AtPAO1 to AtPAO5) contribute homeostasis. AtPAO5 catalyzes the back-conversion of thermospermine (T-Spm) spermidine and plays a role development, xylem differentiation, abiotic stress tolerance. present study, verify whether T-Spm metabolism can be exploited as new route improve tolerance crops investigate underlying mechanisms, tomato (Solanum lycopersicum) homologs were identified (SlPAO2, SlPAO3, SlPAO4) CRISPR/Cas9-mediated loss-of-function slpao3 mutants obtained. Morphological, molecular, analyses showed that display increased levels exhibit changes growth parameters, number size elements, expression auxin- gibberellin-related genes compared wild-type plants. The also characterized by improved drought stress, which attributed diminished hydraulic conductivity limits water loss, well reduced vulnerability embolism. Altogether, this study evidences conservation, though with some significant variations, T-Spm-mediated regulatory mechanisms controlling differentiation across different species highlights improving while not constraining growth.

Language: Английский

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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, Journal Year: 2024, Volume and Issue: 15

Published: June 25, 2024

Introduction Drought-induced embolism formation in conifers is associated with several tracheid and pit traits, which vary parallel from stem apex to base. We tested whether this axial anatomical variability a progressive variation vulnerability along the Methods assessed hydraulic diameter ( Dh ), mean membrane area PMA ) xylem pressure at 50% loss of conductivity P50 on longitudinal segments extracted different distances DFA Picea abies an Abies alba tree. Results In both trees, scaled 0.2 . varied for more than 3 MPa treetop base, according scaling - -0.2 The largest , occurred <1.5 m. isometrically (exponent b =1.2). Pit traits proportionally lumen diameter. Discussion conclusions Apex-to-base trends variations P50, suggest strong structure-function relationship that influenced by Although effect has not been extensively explored previously, we propose analyzing between could be crucial comprehensive assessment individual level.

Language: Английский

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