Functional xylem characteristics associated with drought‐induced embolism in angiosperms

New Phytologist, Год журнала: 2022, Номер 236(6), С. 2019 - 2036

Опубликована: Авг. 30, 2022

Hydraulic failure resulting from drought-induced embolism in the xylem of plants is a key determinant reduced productivity and mortality. Methods to assess this vulnerability are difficult achieve at scale, leading alternative metrics correlations with more easily measured traits. These efforts have led longstanding pervasive assumed mechanistic link between vessel diameter angiosperms. However, there least two problems assumption that requires critical re-evaluation: (1) our current understanding does not provide explanation why increased width should lead greater vulnerability, (2) most recent advancements nanoscale processes suggest direct driver. Here, we review data physiological comparative wood anatomy studies, highlighting potential anatomical physicochemical drivers formation spread. We then put forward knowledge gaps, emphasising what known, unknown speculation. A meaningful evaluation diameter-vulnerability will require better biophysical level determine spread, which turn accurate predictions how water transport affected by drought.

Язык: Английский

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Plant Strategies

Oxford University Press eBooks, Год журнала: 2023, Номер unknown

Опубликована: Июль 27, 2023

Abstract Plants have evolved a remarkable array of adaptive solutions to the existential problem survival and reproduction in world where disturbances can be deadly, resources are scarce, competition is cutthroat. inherited phenotypic traits that increased their chance success, these indicators strategies for establishment survival. A plant strategy thought as “how species sustains population” (Westoby, 1998, p. 214) because all successful must positive demographic outcomes habitats which they adapted. This book aims articulate coherent framework studying unifies demography with functional ecology advance prediction ecology. Central this traits: heritable morphological, physiological, phenological attributes plants influence therefore drive fitness differences among species.

Язык: Английский

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

Functional Ecology, Год журнала: 2025, Номер unknown

Опубликована: Янв. 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.

Язык: Английский

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Catastrophic hydraulic failure and tipping points in plants

Plant Cell & Environment, Год журнала: 2022, Номер 45(8), С. 2231 - 2266

Опубликована: Апрель 8, 2022

Water inside plants forms a continuous chain from water in soils to the evaporating leaf surfaces. Failures this result reduced transpiration and photosynthesis are caused by soil drying and/or cavitation-induced xylem embolism. Xylem embolism plant hydraulic failure share several analogies 'catastrophe theory' dynamical systems. These catastrophes often represented physiological ecological literature as tipping points when control variables exogenous (e.g., potential) or endogenous allowed vary on time scales much longer than associated with cavitation events. Here, hydraulics viewed perspective of at multiple spatial is considered attention bubble expansion within conduit, organ-scale vulnerability embolism, whole-plant biomass proxy for function. The safety-efficiency tradeoff, segmentation maximum examined using framework. Underlying mechanisms fine such pit membranes cell-wall mechanics, intermediate network properties larger soil-tree pathways discussed. Understudied areas also flagged where progress urgently needed.

Язык: Английский

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Abscisic acid acts essentially on stomata, not on the xylem, to improve drought resistance in tomato

Plant Cell & Environment, Год журнала: 2023, Номер 46(11), С. 3229 - 3241

Опубликована: Авг. 1, 2023

Drought resistance is essential for plant production under water-limiting environments. Abscisic acid (ABA) plays a critical role in stomata but its impact on hydraulic function beyond the far less studied. We selected genotypes differing their ability to accumulate ABA investigate drought-induced dysfunction. All exhibited similar leaf and stem embolism regardless of differences levels. Their was also similar. Differences were only observed between two extreme genotypes: sitiens (sit; strong ABA-deficient mutant) sp12 (a transgenic line that constitutively overaccumulates ABA), where water potential inducing 50% 0.25 MPa lower than sit. Maximum stomatal minimum conductances considerably plants with higher (wild type [WT] sp12) mutants. Variations gas exchange across associated levels density size. The loss meant lethal potentials occurred later during drought plants, followed by WT, then Therefore, primary pathway which enhances via declines loss, delays dehydration

Язык: Английский

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Stem and leaf xylem of angiosperm trees experiences minimal embolism in temperate forests during two consecutive summers with moderate drought

Plant Biology, Год журнала: 2022, Номер 24(7), С. 1208 - 1223

Опубликована: Янв. 6, 2022

Drought events may increase the likelihood that plant water transport system becomes interrupted by embolism. Yet our knowledge about temporal frequency of xylem embolism in field is frequently lacking, as it requires detailed, long-term measurements. We measured resistance and midday potentials during consecutive summers 2019 2020 to estimate maximum levels leaf stem ten temperate angiosperm tree species. also studied vessel pit membrane characteristics based on light electron microscopy corroborate potential differences between leaves stems. Apart from A. pseudoplatanus Q. petraea, eight species experienced minimum were close or below those required initiate Water corresponding ca. 12% loss hydraulic conductivity (PLC) could occur six species, while considerable around 50% PLC limited B. pendula C. avellana. There was a general agreement stems leaves, with being equally more resistant than Also, significantly correlated intervessel thickness (TPM ) for stems, but not diameter total surface area vessel. Our data indicate low amounts most moderate summer drought, are uncommon. Moreover, experimental TPM show generally no vulnerable xylem.

Язык: Английский

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In vivo monitoring of drought‐induced embolism in Callitris rhomboidea trees reveals wide variation in branchlet vulnerability and high resistance to tissue death

New Phytologist, Год журнала: 2021, Номер 233(1), С. 207 - 218

Опубликована: Окт. 9, 2021

Damage to the plant water transport system through xylem cavitation is known be a driver of death in drought conditions. However, lack techniques continuously monitor embolism whole plants vivo has hampered our ability investigate both how this damage propagates and possible mechanistic link between tissue death. Using optical fluorescence sensors, we monitored drought-induced accumulation photosynthetic throughout canopy drought-resistant conifer, Callitris rhomboidea, during treatments c. 1 month duration. We show that can trees extended periods stress. Under these conditions, vulnerability varied widely among branchlets, with only recorded once > 90% was cavitated. The variation branchlet important implications for understanding like C. rhomboidea survive drought, high resistance branchlets points runaway as likely branch tips.

Язык: Английский

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The relative area of vessels in xylem correlates with stem embolism resistance within and between genera

Tree Physiology, Год журнала: 2022, Номер 43(1), С. 75 - 87

Опубликована: Сен. 7, 2022

The resistance of xylem conduits to embolism is a major factor defining drought tolerance and can set the distributional limits species across rainfall gradients. Recent work suggests that proximity vessels neighbors increases vulnerability conduit. We therefore investigated whether relative vessel area correlates with intra- inter-generic variation in pairs or triplets from genera Acer, Cinnamomum, Ilex, Quercus Persea, adapted environments differing aridity. used optical method assess stems conducted anatomical measurements on which was quantified. Vessel lumen fraction (VLF) correlated within genera. A low VLF likely gas movement between conduits, by diffusion advection, whereas high enhances transport thorough increased conduit-to-conduit connectivity reduced distances likelihood propagation. suggest rate due local pressure differences network central driver propagation angiosperm vessels.

Язык: Английский

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Xylem anatomical and hydraulic traits vary within crown but not respond to water and nitrogen addition in Populus tomentosa

Agricultural Water Management, Год журнала: 2023, Номер 278, С. 108169 - 108169

Опубликована: Янв. 18, 2023

Nitrogen (N) and water availability are the two crucial factors confining tree growth forest productivity. Irrigation, fertilization, combined fertigation commonly applied to plantation forests for improving However, how xylem vasculature responds these management practices remains poorly understood. Here we investigated responses of growth, anatomical structure, hydraulics upper, middle, lower canopy branches in a 6-year-old Populus tomentosa subjected four years irrigation treatments. The results showed that an improvement only occurred treatment while addition N treatments did not have cumulative effect on growth. Most traits, including vessel hydraulic diameter (Dh), density (VD), fraction (VF), double wall thickness (t), potential specific sapwood conductivity (Kp), fiber lumen ratio (Tf/Df), reinforcement (t/b)2, wood (WD) all conserved plasticity long-term fertigation, despite different rate, implying aboveground biomass accumulation may decoupled from branch-level traits. Besides, alterations other factors, stomatal regulation strategy crown structure with soil availabilities, might better explain variation In contrast, greater variations branch traits were detected across layers. upper safety characterized by narrower denser vessels, higher cell ratio, compared canopy, efficiency (Kp) remained constant crown, thus highlighting priority over construction xylem. Overall, our study revealed response pattern P. management, which facilitates comprehensive understanding mechanisms underpinning influence nutrients performance fast-growing species' plantations.

Язык: 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, Год журнала: 2023, Номер 239(4), С. 1239 - 1252

Опубликована: Июнь 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.

Язык: Английский

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