Root hydraulic conductivity and transpiration in Arabidopsis : coordination revealed by a high-stomatal-density mutant
Abstract Background and aims: Understanding the coordination between root and shoot hydraulics is fundamental for improving plant performance under water stress. In this study, we investigated how shoot traits that enhance transpiration influence root hydraulic properties, using the Arabidopsis tha...
| Main Authors: | , , , , , |
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| Format: | Artículo |
| Language: | Inglés |
| Published: |
BioRxiv
2026
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| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.12123/25035 https://www.biorxiv.org/content/10.64898/2025.12.17.694893v1 https://doi.org/10.64898/2025.12.17.694893 |
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| author | Cáceres, Pablo D. Manacorda, Carlos Augusto Sutka, Moira Asurmendi, Sebastian Amodeo, Gabriela Baroli, Irene |
| author_browse | Amodeo, Gabriela Asurmendi, Sebastian Baroli, Irene Cáceres, Pablo D. Manacorda, Carlos Augusto Sutka, Moira |
| author_facet | Cáceres, Pablo D. Manacorda, Carlos Augusto Sutka, Moira Asurmendi, Sebastian Amodeo, Gabriela Baroli, Irene |
| author_sort | Cáceres, Pablo D. |
| collection | INTA Digital |
| description | Abstract
Background and aims: Understanding the coordination between root and shoot hydraulics is fundamental for improving plant performance under water stress. In this study, we investigated how shoot traits that enhance transpiration influence root hydraulic properties, using the Arabidopsis thaliana double mutant epf1 epf2, characterized by high stomatal density and increased transpiration.
Methods: Plant lines epf1 epf2 and Col-0 (wild type) were grown hydroponically and compared for stomatal traits, rate of water loss, leaf and root water relations, aquaporin expression, and root hydraulic conductivity (Lpr). Then, to assess responses to water deficit, osmotic stress was induced by adding 2% polyethylene glycol (PEG) to the nutrient solution seven days before measurements.
Key results: The epf1 epf2 double mutant exhibited ∼150% higher stomatal density, yet stomatal conductance and short-term rosette water loss increased by only ∼30% relative to wild type. Despite higher water loss, the mutant maintained its leaf relative water content, concomitant with a more negative leaf osmotic potential; root osmotic potential was similar between genotypes. epf1 epf2 showed lower Lpr than Col-0. Aquaporin transcript levels and the relative aquaporin contribution to root water transport did not differ between genotypes. Under osmotic stress, Col-0 instead showed lower Lpr than epf1 epf2, again without changes in aquaporin expression or relative contribution.
Conclusions: Our results highlight an active contribution of the root as a modulator of the whole-plant hydraulic balance. Across scenarios where xylem tension was expected to increase, stomatal aperture and Lpr decreased. We suggest that enhanced transpiration elevates xylem tension, which acts as a long-distance cue, eliciting coordinated reductions in stomatal aperture and Lpr, thereby constraining water flux. |
| format | Artículo |
| id | INTA25035 |
| institution | Instituto Nacional de Tecnología Agropecuaria (INTA -Argentina) |
| language | Inglés |
| publishDate | 2026 |
| publishDateRange | 2026 |
| publishDateSort | 2026 |
| publisher | BioRxiv |
| publisherStr | BioRxiv |
| record_format | dspace |
| spelling | INTA250352026-01-23T13:24:43Z Root hydraulic conductivity and transpiration in Arabidopsis : coordination revealed by a high-stomatal-density mutant Cáceres, Pablo D. Manacorda, Carlos Augusto Sutka, Moira Asurmendi, Sebastian Amodeo, Gabriela Baroli, Irene Root Hydraulic Conductivity Transpiration Stomata Osmotic Stress Cell Communication Moisture Content Conductancia Hidráulica de Raíces Transpiración Estoma Estrés osmótico Comunicación Celular Contenido de Humedad Arabidopsis Aquaporin Acuaporina Abstract Background and aims: Understanding the coordination between root and shoot hydraulics is fundamental for improving plant performance under water stress. In this study, we investigated how shoot traits that enhance transpiration influence root hydraulic properties, using the Arabidopsis thaliana double mutant epf1 epf2, characterized by high stomatal density and increased transpiration. Methods: Plant lines epf1 epf2 and Col-0 (wild type) were grown hydroponically and compared for stomatal traits, rate of water loss, leaf and root water relations, aquaporin expression, and root hydraulic conductivity (Lpr). Then, to assess responses to water deficit, osmotic stress was induced by adding 2% polyethylene glycol (PEG) to the nutrient solution seven days before measurements. Key results: The epf1 epf2 double mutant exhibited ∼150% higher stomatal density, yet stomatal conductance and short-term rosette water loss increased by only ∼30% relative to wild type. Despite higher water loss, the mutant maintained its leaf relative water content, concomitant with a more negative leaf osmotic potential; root osmotic potential was similar between genotypes. epf1 epf2 showed lower Lpr than Col-0. Aquaporin transcript levels and the relative aquaporin contribution to root water transport did not differ between genotypes. Under osmotic stress, Col-0 instead showed lower Lpr than epf1 epf2, again without changes in aquaporin expression or relative contribution. Conclusions: Our results highlight an active contribution of the root as a modulator of the whole-plant hydraulic balance. Across scenarios where xylem tension was expected to increase, stomatal aperture and Lpr decreased. We suggest that enhanced transpiration elevates xylem tension, which acts as a long-distance cue, eliciting coordinated reductions in stomatal aperture and Lpr, thereby constraining water flux. Instituto de Biotecnología Fil: Cáceres, Pablo D. Universidad de Buenos Aires (UBA). Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad, Biología Experimental y Aplicada. Departamento de Biodiversidad y Biología Experimental; Argentina Fil: Cáceres, Pablo D. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Argentina Fil: Manacorda, Carlos Augusto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Manacorda, Carlos Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Argentina Fil: Sutka, Moira. Universidad de Buenos Aires (UBA). Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad, Biología Experimental y Aplicada. Departamento de Biodiversidad y Biología Experimental; Argentina Fil: Sutka, Moira. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Argentina Fil: Asurmendi, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Asurmendi, Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Argentina Fil: Amodeo, Gabriela. Universidad de Buenos Aires (UBA). Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad, Biología Experimental y Aplicada. Departamento de Biodiversidad y Biología Experimental; Argentina Fil: Amodeo, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Argentina Fil: Baroli, Irene. Universidad de Buenos Aires (UBA). Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad, Biología Experimental y Aplicada. Departamento de Biodiversidad y Biología Experimental; Argentina Fil: Baroli, Irene. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Argentina 2026-01-23T13:12:15Z 2026-01-23T13:12:15Z 2025-12 info:ar-repo/semantics/artículo info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion http://hdl.handle.net/20.500.12123/25035 https://www.biorxiv.org/content/10.64898/2025.12.17.694893v1 https://doi.org/10.64898/2025.12.17.694893 eng info:eu-repograntAgreement/INTA/2023-PD-L03-I084, Estreses bióticos y abióticos en plantas. Estudios fisiológicos y patológicos para el diseño de estrategias de mejoramiento y manejo info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) application/pdf BioRxiv BioRxiv : the preprint server for biology (December 17, 2025) |
| spellingShingle | Root Hydraulic Conductivity Transpiration Stomata Osmotic Stress Cell Communication Moisture Content Conductancia Hidráulica de Raíces Transpiración Estoma Estrés osmótico Comunicación Celular Contenido de Humedad Arabidopsis Aquaporin Acuaporina Cáceres, Pablo D. Manacorda, Carlos Augusto Sutka, Moira Asurmendi, Sebastian Amodeo, Gabriela Baroli, Irene Root hydraulic conductivity and transpiration in Arabidopsis : coordination revealed by a high-stomatal-density mutant |
| title | Root hydraulic conductivity and transpiration in Arabidopsis : coordination revealed by a high-stomatal-density mutant |
| title_full | Root hydraulic conductivity and transpiration in Arabidopsis : coordination revealed by a high-stomatal-density mutant |
| title_fullStr | Root hydraulic conductivity and transpiration in Arabidopsis : coordination revealed by a high-stomatal-density mutant |
| title_full_unstemmed | Root hydraulic conductivity and transpiration in Arabidopsis : coordination revealed by a high-stomatal-density mutant |
| title_short | Root hydraulic conductivity and transpiration in Arabidopsis : coordination revealed by a high-stomatal-density mutant |
| title_sort | root hydraulic conductivity and transpiration in arabidopsis coordination revealed by a high stomatal density mutant |
| topic | Root Hydraulic Conductivity Transpiration Stomata Osmotic Stress Cell Communication Moisture Content Conductancia Hidráulica de Raíces Transpiración Estoma Estrés osmótico Comunicación Celular Contenido de Humedad Arabidopsis Aquaporin Acuaporina |
| url | http://hdl.handle.net/20.500.12123/25035 https://www.biorxiv.org/content/10.64898/2025.12.17.694893v1 https://doi.org/10.64898/2025.12.17.694893 |
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