Hydraulic traits are coordinated but decoupled from carbon traits in herbaceous species

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

Published: April 7, 2025

Abstract Plant hydraulic traits primarily define the water regulation strategy, thus enabling a better understanding of vegetation structure, function and dynamics under varying hydro‐environments. Despite being intensively documented in woody species, variation correlation across herbaceous species remain largely understudied. Here, we report on leaf hydraulics nine herbs with contrasting growth forms (graminoid forb). Traits quantifying drought resistance, including potential thresholds triggering xylem embolism (P x ), stomatal closure gs ) or turgor loss point tlp minimum conductance (g min together gas exchange, morphological biomass allocation, were measured pot‐grown plants. In addition, an situ dry‐down was imposed four representative level continuously monitored during dehydration to determine embolism. We found that studied graminoids tended be more tolerant than forbs, although difference safety margin for (HSM st did not differ significantly between these forms. Across P coordinated , but decoupled from exchange traits, maximum photosynthetic rate conductance. Furthermore, no correlations specific area ratio aboveground belowground biomass. For plants experienced dehydration, always preceded onset leaves. Moreover, exhibited distinct strategy despite belonging same form. Our findings contribute herb hydraulics, which will inform prediction grassy ecosystems by providing data guiding classification plant functional types ‘grassy’ ecosystems. Read free Plain Language Summary this article Journal blog.

Language: Английский

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Within‐leaf variation in embolism resistance is not a rule for compound‐leaved angiosperms

American Journal of Botany, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 16, 2024

Abstract Premise Hydraulic segmentation, caused by the difference in embolism resistance across plant organs, provides a sacrificial layer of cheaper like leaves, to protect more costly such as stems, during drought. Within‐leaf hydraulic segmentation has been observed two compound‐leaved tree species, with leaflets being vulnerable than rachis or petiole. Many herbaceous species have compound and some that are associated pulvini at base lamina, which could provide an anatomical means preventing from spreading within leaf because higher number vessel endings pulvinus. Methods We used optical vulnerability method investigate whether differences were tissues six one deciduous leaves. Our selection included both palmately pinnately‐compound leaved each pulvinus leaflets. Results found considerable variation measured, but no evidence leaf. In pulvini, we major events crossing pulvinus, petiole into embolizing same water potential. Conclusions conclude within‐leaf resistance, is not universal phenomenon presence does barrier spread

Language: Английский

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Integrating Gene Expression Analysis and Ecophysiological Responses to Water Deficit in Leaves of Tomato Plants

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: July 5, 2024

Abstract Soil water deficit (WD) is one of the most important abiotic stresses affecting plant survival and crop yield. Despite its economic relevance, many gaps remain in our understanding how crops respond to WD, especially concerning synergistic coordination molecular ecophysiological adaptations delaying damage mortality. In this study, we investigated gene expression imposed by a progressive WD combined it with measurements pointing key thresholds leaves tomato plants. We uncovered transcriptomic changes mature at four stages defined physiological markers relating different intensities: partial stomatal closure, complete after leaf wilting, beginning embolism development veins. By identifying transcription factors (TFs) across these progressively worsening stages, timing impact ABA-(in)dependent regulatory pathways during WD. addition, compared transcriptome young developing versus explored mechanisms that may explain higher tolerance dehydration younger leaves. correlating precise measurements, dataset will serve as framework for future studies comparing responses specific intensities. Highlight Integrated analyses identify underlying

Language: Английский

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New insights into a sensitive life stage: hydraulics of tree seedlings in their first growing season

New Phytologist, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 5, 2024

Summary The first year in a tree's life is characterized by distinct morphological changes, requiring constant adjustments of the hydraulic system. Despite their importance for natural regeneration forests and future vegetation composition, little has been known about hydraulics tree seedlings. At different times across growing season, we analysed xylem area‐specific ( K shoot_Axyl ) leaf shoot_L shoot conductance, as well embolism resistance three temperate conifer trees, two angiosperm trees one shrub, related findings to cell osmotic parameters anatomical traits. Over 10 wk after germination, sharply decreased, then remained stable until end season. Embolism was remarkably low youngest stages but, coupled with an increase wall reinforcement, significantly increased towards autumn. Contemporaneously, water potential at turgor loss saturation decreased. Independent lineage, species growth form, transition from primary secondary resulted less efficient but increasingly more embolism‐resistant system, enabling supply under increasing risk potentials.

Language: Английский

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