1
|
Tulik M, Wojtan R, Jura-Morawiec J. Theoretical considerations regarding the functional anatomical traits of primary and secondary xylem in dragon tree trunk using the example of Dracaena draco. PLANTA 2022; 256:52. [PMID: 35906444 PMCID: PMC9338164 DOI: 10.1007/s00425-022-03966-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
In Dracaena draco trunks, the primary and secondary xylem conduits co-function. Both are resistant to embolism; however, secondary conduits are mainly involved in mechanical support. Monocotyledonous dragon trees (Dracaena spp., Asparagaceae) possess in their trunks both primary and secondary xylem elements, organized into vascular bundles, that for dozens of years co-function and enable the plant to transport water efficiently as well as provide mechanical support. Here, based on the modified Hagen-Poiseuille's formula, we examined the functional anatomical xylem traits of the trunk in two young D. draco individuals to compare their function in both primary and secondary growth. We provided analyses of the: (i) conduits surface sculpture and their cell walls thickness, (ii) conduit diameter and frequency, (iii) hydraulically weighted diameter, (iv) theoretical hydraulic conductivity, (v) area-weighted mean conduit diameter, as well as (vi) vulnerability index. The conduits in primary growth, located in the central part of the trunk, were loosely arranged, had thinner cell walls, larger mean hydraulically weighted diameter, and significantly larger value of the theoretical hydraulic conductivity than conduits in secondary growth, which form a rigid cylinder near the trunk surface. Based on the vulnerability index, both primary and secondary conduits are resistant to embolism. Taking into account the distribution within a trunk, the secondary growth conduits seems to be mainly involved in mechanical support as they are twisted, form structures similar to sailing ropes and have thick cell walls, and a peripheral localization. D. draco has been adapted to an environment with water deficit by distinctive, spatial separation of the xylem elements fulfilling supportive and conductive functions.
Collapse
Affiliation(s)
- Mirela Tulik
- Department of Forest Botany, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland
| | - Rafał Wojtan
- Department of Dendrometry and Forest Productivity, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland
| | - Joanna Jura-Morawiec
- Polish Academy of Sciences Botanical Garden - CBDC in Powsin, Prawdziwka 2, 02-973 Warsaw, Poland
| |
Collapse
|
2
|
Yang D, Zhang Y, Zhou D, Zhang YJ, Peng G, Tyree MT. The hydraulic architecture of an arborescent monocot: ontogeny-related adjustments in vessel size and leaf area compensate for increased resistance. THE NEW PHYTOLOGIST 2021; 231:273-284. [PMID: 33621370 DOI: 10.1111/nph.17294] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
Bamboos are arborescent monocotyledons that have no secondary growth, but can continually produce conduits with diameters appropriate to the current size of the plant. Here, we studied bamboo hydraulic architecture to address the mechanisms involved in compensating for the increase in hydraulic resistance during ontogeny. We measured the hydraulic weighted vessel diameters (Dh ) at different distances from the apex along the stem of Bambusa textilis. The hydraulic resistance of different components and individuals of different heights were quantified using the high-pressure flowmeter method. The Dh showed tip-to-base widening with a scaling exponent in the range of those reported for trees. Although theoretical hydraulic conductivity decreased from base-to-tip, leaf-specific conductivity did not change. Leaves contributed the most to the whole-shoot hydraulic resistance, followed by the leaf-bearing branches. Roots contributed c. 13% to whole-plant resistance. Interestingly, taller individuals showed lower whole-shoot resistance owing to an increased number of resistances in parallel (side-branches), while leaf-specific resistance was independent of plant size. Tip-to-base vessel widening and height-independent constant leaf-specific conductance could be mechanisms for hydraulic optimization in B. textilis. Similar patterns have also been found in woody plants with secondary growth, but this bamboo exhibits them without secondary growth.
Collapse
Affiliation(s)
- Dongmei Yang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China
| | - Yinshuang Zhang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China
| | - Dan Zhou
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China
| | - Yong-Jiang Zhang
- School of Biology and Ecology, University of Maine, Orono, ME, 04469, USA
| | - Guoquan Peng
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China
| | - Melvin T Tyree
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China
| |
Collapse
|
3
|
Emilio T, Lamarque LJ, Torres-Ruiz JM, King A, Charrier G, Burlett R, Conejero M, Rudall PJ, Baker WJ, Delzon S. Embolism resistance in petioles and leaflets of palms. ANNALS OF BOTANY 2020; 124:1173-1184. [PMID: 31227829 PMCID: PMC6943700 DOI: 10.1093/aob/mcz104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 06/17/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND AND AIMS Hydraulic studies are currently biased towards conifers and dicotyledonous angiosperms; responses of arborescent monocots to increasing temperature and drought remain poorly known. This study aims to assess xylem resistance to drought-induced embolism in palms. METHODS We quantified embolism resistance via P50 (xylem pressure inducing 50 % embolism or loss of hydraulic conductivity) in petioles and leaflets of six palm species differing in habitat and phylogenetic relatedness using three techniques: in vivo X-ray-based microcomputed tomography, the in situ flow centrifuge technique and the optical vulnerability method. KEY RESULTS Our results show that P50 of petioles varies greatly in the palm family, from -2.2 ± 0.4 MPa in Dypsis baronii to -5.8 ± 0.3 MPa in Rhapis excelsa (mean ± s.e.). No difference or weak differences were found between petioles and leaf blades within species. Surprisingly, where differences occurred, leaflets were less vulnerable to embolism than petioles. Embolism resistance was not correlated with conduit size (r = 0.37, P = 0.11). CONCLUSIONS This study represents the first estimate of drought-induced xylem embolism in palms across biomes and provides the first step towards understanding hydraulic adaptations in long-lived arborescent monocots. It showed an almost 3-fold range of embolism resistance between palm species, as large as that reported in all angiosperms. We found little evidence for hydraulic segmentation between leaflets and petioles in palms, suggesting that when it happens, hydraulic segregation may lack a clear relationship with organ cost or replaceability.
Collapse
Affiliation(s)
- Thaise Emilio
- Royal Botanic Gardens, Kew, Richmond, UK
- Programa Nacional de Pós-Doutorado (PNPD), Programa de Pós Graduação em Ecologia, Institute of Biology, University of Campinas (UNICAMP), Brazil
| | | | | | - Andrew King
- Synchrotron SOLEIL, L’Orme de Merisiers, Saint-Aubin, Gif-sur-Yvette Cedex, France
| | | | - Régis Burlett
- BIOGECO, INRA, Université de Bordeaux, Pessac, France
| | | | | | | | | |
Collapse
|
4
|
Apgaua DMG, Ishida FY, Tng DYP, Laidlaw MJ, Santos RM, Rumman R, Eamus D, Holtum JAM, Laurance SGW. Functional Traits and Water Transport Strategies in Lowland Tropical Rainforest Trees. PLoS One 2015; 10:e0130799. [PMID: 26087009 PMCID: PMC4472991 DOI: 10.1371/journal.pone.0130799] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 05/26/2015] [Indexed: 11/18/2022] Open
Abstract
Understanding how tropical rainforest trees may respond to the precipitation extremes predicted in future climate change scenarios is paramount for their conservation and management. Tree species clearly differ in drought susceptibility, suggesting that variable water transport strategies exist. Using a multi-disciplinary approach, we examined the hydraulic variability in trees in a lowland tropical rainforest in north-eastern Australia. We studied eight tree species representing broad plant functional groups (one palm and seven eudicot mature-phase, and early-successional trees). We characterised the species’ hydraulic system through maximum rates of volumetric sap flow and velocities using the heat ratio method, and measured rates of tree growth and several stem, vessel, and leaf traits. Sap flow measures exhibited limited variability across species, although early-successional species and palms had high mean sap velocities relative to most mature-phase species. Stem, vessel, and leaf traits were poor predictors of sap flow measures. However, these traits exhibited different associations in multivariate analysis, revealing gradients in some traits across species and alternative hydraulic strategies in others. Trait differences across and within tree functional groups reflect variation in water transport and drought resistance strategies. These varying strategies will help in our understanding of changing species distributions under predicted drought scenarios.
Collapse
Affiliation(s)
- Deborah M. G. Apgaua
- Departamento de Ciências Florestais, Universidade Federal de Lavras, Lavras, Minas Gerais, Brazil
- Centre for Tropical, Environmental, and Sustainability Sciences, College of Marine and Environmental Sciences, James Cook University, Cairns, Queensland, Australia
| | - Françoise Y. Ishida
- Centre for Tropical, Environmental, and Sustainability Sciences, College of Marine and Environmental Sciences, James Cook University, Cairns, Queensland, Australia
| | - David Y. P. Tng
- Centre for Tropical, Environmental, and Sustainability Sciences, College of Marine and Environmental Sciences, James Cook University, Cairns, Queensland, Australia
- * E-mail:
| | - Melinda J. Laidlaw
- Department of Science, Information Technology, Innovation and the Arts,Queensland Herbarium, Brisbane, Queensland, Australia
| | - Rubens M. Santos
- Departamento de Ciências Florestais, Universidade Federal de Lavras, Lavras, Minas Gerais, Brazil
| | - Rizwana Rumman
- School of the Environment, University of Technology, Sydney, New South Wales, Australia
| | - Derek Eamus
- School of the Environment, University of Technology, Sydney, New South Wales, Australia
| | - Joseph A. M. Holtum
- Centre for Tropical, Environmental, and Sustainability Sciences, College of Marine and Environmental Sciences, James Cook University, Cairns, Queensland, Australia
| | - Susan G. W. Laurance
- Centre for Tropical, Environmental, and Sustainability Sciences, College of Marine and Environmental Sciences, James Cook University, Cairns, Queensland, Australia
| |
Collapse
|
5
|
Gatti MG, Campanello PI, Villagra M, Montti L, Goldstein G. Hydraulic architecture and photoinhibition influence spatial distribution of the arborescent palm Euterpe edulis in subtropical forests. TREE PHYSIOLOGY 2014; 34:630-639. [PMID: 24898220 DOI: 10.1093/treephys/tpu039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Physiological characteristics of saplings can be considered one of the most basic constraints on species distribution. The shade-tolerant arborescent palm Euterpe edulis Mart. is endemic to the Atlantic Forest of Argentina, Brazil and Paraguay. At a local scale, saplings of this species growing in native forests are absent in gaps. We tested the hypothesis whether sensitivity to photoinhibition or hydraulic architecture constrains the distribution of E. edulis saplings in sun-exposed forest environments. Using shade houses and field studies, we evaluated growth, survival, hydraulic traits and the susceptibility of Photosystem II to photoinhibition in E. edulis saplings under different growth irradiances. Survival rates in exposed sites in the field were very low (a median of 7%). All saplings exhibited photoinhibition when exposed to high radiation levels, but acclimation to a high radiation environment increased the rate of recovery. Petiole hydraulic conductivity was similar across treatments regardless of whether it was expressed per petiole cross-sectional area or per leaf area. At the plant level, investment in conductive tissues relative to leaf area (Huber values) increased with increasing irradiance. Under high irradiance conditions, plants experienced leaf water potentials close to the turgor-loss point, and leaf hydraulic conductance decreased by 79% relative to its maximum value. Euterpe edulis saplings were able to adjust their photosynthetic traits to different irradiance conditions, whereas hydraulic characteristics at the leaf level did not change across irradiance treatments. Our results indicate that uncoupling between water demand and supply to leaves apparently associated with high resistances to water flow at leaf insertion points, in addition to small stems with low water storage capacity, weak stomatal control and high vulnerability of leaves to hydraulic dysfunction, are the main ecophysiological constraints that prevent the growth and survival of E. edulis saplings in gaps in the native forest where native lianas and bamboos show aggressive growth.
Collapse
Affiliation(s)
- M Genoveva Gatti
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina Laboratorio de Ecología Funcional, Dept Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina Present address: IBS-Instituto de Biología Subtropical, Universidad Nacional de Misiones, Bertoni 85, 3370 Puerto Iguazú, Misiones, Argentina
| | - Paula I Campanello
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina Laboratorio de Ecología Funcional, Dept Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina Present address: IBS-Instituto de Biología Subtropical, Universidad Nacional de Misiones, Bertoni 85, 3370 Puerto Iguazú, Misiones, Argentina
| | - Mariana Villagra
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina Laboratorio de Ecología Funcional, Dept Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina Present address: IBS-Instituto de Biología Subtropical, Universidad Nacional de Misiones, Bertoni 85, 3370 Puerto Iguazú, Misiones, Argentina
| | - Lía Montti
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina Laboratorio de Ecología Funcional, Dept Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina Present address: Instituto de Ecología Regional (IER), Universidad Nacional de Tucumán, CC 34, 4107 Yerba Buena, Tucumán, Argentina
| | - Guillermo Goldstein
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina Laboratorio de Ecología Funcional, Dept Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina Department of Biology, University of Miami, PO Box 249118, Coral Gables, FL 33124, USA
| |
Collapse
|
6
|
Wang N, Liu W, Huang J, Ma K. The structure-mechanical relationship of palm vascular tissue. J Mech Behav Biomed Mater 2014; 36:1-11. [PMID: 24768963 DOI: 10.1016/j.jmbbm.2014.04.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 04/02/2014] [Accepted: 04/05/2014] [Indexed: 11/18/2022]
Abstract
The structure-mechanical relationship of palm sheath is studied with numerical and experimental methods. The cellular structure of the vascular tissue is rebuilt with an image-based reconstruction method and used to create finite element models. The validity of the models is firstly verified with the results from the tensile tests. Then, the cell walls inside each of the specific regions (fiber cap, vessel, xylem, etc.) are randomly removed to obtain virtually imperfect structures. By comparing the magnitudes of performance degradation in the different imperfect structures, the influences of each region on the overall mechanical performances of the vascular tissue are discussed. The longitudinal stiffness and yield strength are sensitive to the defects in the vessel regions. While in the transverse directions (including the radial and tangential directions), the parenchymatous tissue determines the mechanical properties of the vascular tissue. Moreover, the hydraulic, dynamic response and energy absorption behavior of the vascular tissue are numerically explored. The flexibility of natural palm tissue enhances its impact resistance. Under the quasi-static compression, the cell walls connecting the fiber cap and the vessel dissipate more energy. The dominant role of the fiber cap in the plastic energy dissipation under high-speed impact is observed. And the radially-arranged fiber cap also allows the palm tissue to improve its tangential mechanical performances under hydraulic pressure.
Collapse
Affiliation(s)
- Ningling Wang
- School of Mechanical and Automotive Engineering, South China University of Technology, 510640 Guangzhou, China
| | - Wangyu Liu
- School of Mechanical and Automotive Engineering, South China University of Technology, 510640 Guangzhou, China.
| | - Jiale Huang
- School of Mechanical and Automotive Engineering, South China University of Technology, 510640 Guangzhou, China
| | - Ke Ma
- School of Electronic and Information Engineering, South China University of Technology, 510640 Guangzhou, China
| |
Collapse
|