Gold perfusion experiments support the multi‐layered, mesoporous nature of intervessel pit membranes in angiosperm xylem

New Phytologist, Journal Year: 2024, Volume and Issue: 242(2), P. 493 - 506

Published: Feb. 25, 2024

Fluid transport across intervessel pit membranes of angiosperm xylem plays a major role in plant transpiration, with resistance largely depending on pore constriction sizes. Traditionally, fluid particles traversing are assumed to cross single instead multiple constrictions. We tested multi-layered membrane model eight species by estimating the size frequency constrictions relation thickness and compared modelled data perfusion characteristics nanoscale gold based transmission electron microscopy. The showed similar patterns measured number perfused particle sizes inside membranes, although values were 10-50 times below data. Small enter most easily, especially when injected thin membranes. trapping becomes more likely increasing thickness. While quantitative differences between experimental due various practical limitations, their qualitative agreement supports Pore 5 50 nm realistic, confirm mesoporous nature

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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Exploring within‐plant hydraulic trait variation: A test of the vulnerability segmentation hypothesis

Plant Cell & Environment, Journal Year: 2023, Volume and Issue: 46(9), P. 2726 - 2746

Published: June 20, 2023

Abstract Observations show vulnerability segmentation between stems and leaves is highly variable within environments. While a number of species exhibit conventional (stem leaf ), others no reverse ). We developed hydraulic model to test hypotheses about how it interacts with other traits impact plant conductance. do this using series experiments across broad parameter space case study two contrasting patterns: Quercus douglasii Populus trichocarpa . found that while helps preserve conductance in stem tissues, can better maintain the combined stem‐leaf pathway, particularly when plants have more vulnerable s greater resistance leaves. These findings impacts are dependent upon traits, notably segmentation, finding could assist interpretation observations segmentation. Further needed examine transpiration rates recovery from water stress.

Language: Английский

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Systemic effects of the vapor pressure deficit on the physiology and productivity of protected vegetables

Vegetable Research, Journal Year: 2023, Volume and Issue: 3(1), P. 0 - 0

Published: Jan. 1, 2023

In previous decades, the global temperature has risen, and saturation vapor pressure deficit (VPD) increased. VPD is an important environmental factor affecting crops, especially their yields. However, effects of various conditions on water transport dynamics, anatomical structure, stomatal morphology, photosynthetic physiology, nutrient absorption, yield, quality remain unclear. Many studies have shown that atmospheric transpiration enhanced, dynamics in soil-plant-atmosphere continuum potential gradient are increased, crop reduced under high VPD. Crops undergone a series changes enhanced adaptation to high-VPD environments. Mesophyll thickness conductance size decreased, this led reductions rate accumulation. High seriously reduces yield use efficiency protected vegetables but improves fruit color flavor quality. Reductions can improve vegetables, alter structure promote photosynthesis, increase nutritional quality, efficiency. Comprehensive analysis effect physiology productivity will provide insights aid cultivation with yield.

Language: Английский

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Physiological mechanisms and drought resistance assessment of four dominant species on the Loess Plateau under drought stress

Physiologia Plantarum, Journal Year: 2025, Volume and Issue: 177(3)

Published: May 1, 2025

Abstract The escalating frequency and severity of droughts have caused growth decline increased mortality risk for plantations on the Loess Plateau. main aim this study was to explore physiological mechanisms four native dominant species during drought‐induced evaluate their drought resistance capabilities. Drought induced by withholding water from potted seedings, we compared patterns in pit membrane damage, hydraulic function, non‐structural carbohydrates (NSC) dynamics across tree with distinct anatomical features. Our findings reveal species‐specific vulnerability thresholds: Pinus tabulaeformis (−2.86 Mpa), Quercus liaotungensis (−1.92 Robinia pseudoacacia (−0.109 Syringa reticulata (−0.93 Mpa). Additionally, stress found compromise integrity, potential thresholds identified as R.pseudoacacia (−1.37 S. (−2.20 Q. (−2.39 P. (−1.85 concludes that R. exhibit greater susceptibility failure under severe conditions, leading risks. In contrast, demonstrate enhanced tolerance survival capacity. research elucidates mortality, emphasizing critical role damage process. These not only provide valuable insights into but also establish a scientific foundation future artificial forest transformation initiatives

Language: Английский

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Elevated CO2 concentration increases maize growth under water deficit or soil salinity but with a higher risk of hydraulic failure

Journal of Experimental Botany, Journal Year: 2023, Volume and Issue: 75(1), P. 422 - 437

Published: Sept. 15, 2023

Climate change presents a challenge for plants to acclimate their water relations under changing environmental conditions, and may increase the risks of hydraulic failure stress. In this study, maize were acclimated two different CO2 concentrations ([CO2]; 400 ppm 700 ppm) while either stress (WS) or soil salinity (SS) treatments, growth traits examined in detail. Both WS SS inhibited had significant impacts on traits. particular, potential at 50% loss stem conductance (P50) decreased by 1 MPa both treatments ppm. When subjected elevated [CO2], showed improved 7-23%. Elevated [CO2] also significantly increased xylem vulnerability (measured as conductivity with decreasing pressure), resulting smaller safety margins. According plant desiccation model, critical degree (time×vapor pressure deficit) that could tolerate drought was reduced 43-64% [CO2]. addition, sensitivity analysis P50 most important trait determining degree. Thus, our results demonstrated whilst benefited SS, it interfered acclimation, thereby potentially placing higher risk mortality.

Language: Английский

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Ageing-induced shrinkage of intervessel pit membranes in xylem of Clematis vitalba modifies its mechanical properties as revealed by atomic force microscopy

Frontiers in Plant Science, Journal Year: 2023, Volume and Issue: 14

Published: Jan. 23, 2023

Bordered pit membranes of angiosperm xylem are anisotropic, mesoporous media between neighbouring conduits, with a key role in long distance water transport. Yet, their mechanical properties poorly understood. Here, we aim to quantify the stiffness intervessel over various growing seasons. By applying an AFM-based indentation technique "Quantitative Imaging" measured effective elastic modulus (

Language: Английский

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Enhanced drought resistance in tomato via reduced auxin sensitivity: delayed dehydration and improved leaf resistance to embolism

Physiologia Plantarum, Journal Year: 2024, Volume and Issue: 176(3)

Published: May 1, 2024

Abstract Auxins are master regulators of plant development and auxin perception mutants display smaller leaves, lower transpiration, narrower xylem vessels than their corresponding wild types. Here, we evaluated whether the leaf embolism resistance overall to drought altered in mutant diageotropica ( dgt ). Our assessments demonstrate that tomato exhibit considerably stems (‐24%), petioles (‐43%), midribs (‐34%) type. Alongside vessels, exhibited greater cell wall thickness‐to‐conduit diameter The water potential at 50% cumulative (P 50 ) type was ‐1.39 ‐1.14 MPa, respectively. Plants also higher stomatal safety margin (water difference between closure P ), needed a longer time reach dry‐down experiment, showed faster recovery gas exchange upon rehydration impaired signaling resulted canopy area conductance, which likely contributed delaying for plants hydraulic damage during drought. These findings clear association structural physiological changes improved against drought‐induced dysfunction mutant.

Language: Английский

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Xylem Hydraulics of Two Temperate Tree Species with Contrasting Growth Rates

Plants, Journal Year: 2024, Volume and Issue: 13(24), P. 3575 - 3575

Published: Dec. 21, 2024

Hydraulic functionality is crucial for tree productivity and stress tolerance. According to the theory of fast–slow economics spectrum, adaptive strategies different species diverge along a spectrum defined by coordination trade-offs suite functional traits. The fast- slow-growing are expected differ in hydraulic efficiency safety; however, there still lack investigation on mechanistic association between growth rate functionality. Here, common garden condition, we measured radial traits fast-growing (Populus alba L. × P. berolinensis Dippel) (Acer truncatum Bunge), which both important afforestation northern China. In line with contrasts wood anatomical at tissue pit levels two species, stem conductivity Populus was significantly higher than that Acer but resistance drought-induced xylem cavitation opposite. A trade-off safety observed across sampled trees species. Higher water-transport supports greater leaf net photosynthetic carbon assimilation capacity hence facilitates fast growth, while conservative result slower enhanced drought

Language: Английский

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The optical method based on gas injection overestimates leaf vulnerability to xylem embolism in three woody species

Tree Physiology, Journal Year: 2023, Volume and Issue: 43(10), P. 1784 - 1795

Published: July 10, 2023

Plant hydraulic traits related to leaf drought tolerance, like the water potential at turgor loss point (TLP) and inducing 50% of conductance (P50), are extremely useful predict impacts on plants. While novel techniques have allowed inclusion TLP in studies targeting a large group species, fast reliable protocols measure P50 still lacking. Recently, optical method coupled with gas injection (GI) technique has been proposed as possibility speed up estimation. Here, we present comparison vulnerability curves (OVcs) measured three woody namely Acer campestre (Ac), Ostrya carpinifolia (Oc) Populus nigra (Pn), based bench dehydration (BD) or GI detached branches. For Pn, also compared data direct micro-computed tomography (micro-CT) imaging both intact saplings cut shoots subjected BD. Based BD procedure, Ac, Oc Pn had values -2.87, -2.47 -2.11 MPa, respectively, while procedure overestimated (-2.68, -2.04 -1.54 MPa for respectively). The overestimation was higher than likely reflecting species-specific vessel lengths. According micro-CT observations performed midrib showed none very few embolized conduits -1.2 consistent OVcs obtained but odds that derived basis GI. Overall, our suggest coupling might not be quantify since it could affected by 'open-vessel' artifact. Accurate detection xylem embolism vein network should BD, preferably up-rooted

Language: Английский

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