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Poyatos C, Sacristán-Bajo S, Tabarés P, Prieto-Benítez S, Teso MLR, Torres E, Morente-López J, Lara-Romero C, Iriondo JM, Fernández AG. Differential patterns of within- and between-population genetically based trait variation in Lupinus angustifolius. ANNALS OF BOTANY 2023; 132:541-552. [PMID: 37647862 PMCID: PMC10667004 DOI: 10.1093/aob/mcad123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 08/28/2023] [Indexed: 09/01/2023]
Abstract
BACKGROUND AND AIMS Within-population genetic and phenotypic variation play a key role in the development of adaptive responses to environmental change. Between-population variation is also an essential element in assessing the evolutionary potential of species in response to changes in environmental conditions. In this context, common garden experiments are a useful tool to separate the genetic and environmental components of phenotypic variation. We aimed to assess within- and between-population phenotypic variation of Lupinus angustifolius L. in terms of its evolutionary potential to adapt to ongoing climate change. METHODS We evaluated populations' phenotypic variation of foliar, phenological and reproductive traits with a common garden experiment. Patterns of functional trait variation were assessed with (1) mixed model analyses and coefficients of variation (CVs) with confidence intervals, (2) principal component analyses (PCAs) and (3) correlations between pairs of traits. Analyses were performed at the population level (four populations) and at the latitude level (grouping pairs of populations located in two latitudinal ranges). KEY RESULTS Phenotypic variation had a significant genetic component associated with a latitudinal pattern. (1) Mixed models found lower specific leaf area, advanced flowering phenology and lower seed production of heavier seeds in southern populations, whereas CV analyses showed lower within-latitude variation especially in phenological and reproductive traits in southern populations. (2) PCAs showed a clearer differentiation of phenotypic variation between latitudes than between populations. (3) Correlation analyses showed a greater number of significant correlations between traits in southern populations (25 vs. 13). CONCLUSIONS Between-population phenotypic variation was determined by contrasting temperature and drought at different latitude and elevation. Southern populations had differential trait values compatible with adaptations to high temperatures and drought. Moreover, they had lower within-population variation and a greater number of trait correlations probably as a result of these limiting conditions, making them more vulnerable to climate change.
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Affiliation(s)
- Cristina Poyatos
- Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain
| | - Sandra Sacristán-Bajo
- Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain
| | - Pablo Tabarés
- Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain
| | | | - María Luisa Rubio Teso
- Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain
| | - Elena Torres
- Departamento de Biotecnología-Biología Vegetal, Universidad Politécnica de Madrid, Av. Puerta de Hierro 2-4, 28040, Madrid, Spain
| | - Javier Morente-López
- Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain
- Grupo de Ecología y Evolución en Islas, Instituto de Productos Naturales y Agrobiología (IPNA-CSIC), Avda. Astrofísico Francisco Sánchez 3, 38206, San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain
| | - Carlos Lara-Romero
- Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain
| | - José María Iriondo
- Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain
| | - Alfredo García- Fernández
- Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain
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Castro Sánchez-Bermejo P, Davrinche A, Matesanz S, Harpole WS, Haider S. Within-individual leaf trait variation increases with phenotypic integration in a subtropical tree diversity experiment. THE NEW PHYTOLOGIST 2023; 240:1390-1404. [PMID: 37710419 DOI: 10.1111/nph.19250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 08/10/2023] [Indexed: 09/16/2023]
Abstract
Covariation of plant functional traits, that is, phenotypic integration, might constrain their variability. This was observed for inter- and intraspecific variation, but there is no evidence of a relationship between phenotypic integration and the functional variation within single plants (within-individual trait variation; WTV), which could be key to understand the extent of WTV in contexts like plant-plant interactions. We studied the relationship between WTV and phenotypic integration in c. 500 trees of 21 species in planted forest patches varying in species richness in subtropical China. Using visible and near-infrared spectroscopy (Vis-NIRS), we measured nine leaf morphological and chemical traits. For each tree, we assessed metrics of single and multitrait variation to assess WTV, and we used plant trait network properties based on trait correlations to quantify phenotypic integration. Against expectations, strong phenotypic integration within a tree led to greater variation across leaves. Not only this was true for single traits, but also the dispersion in a tree's multitrait hypervolume was positively associated with tree's phenotypic integration. Surprisingly, we only detected weak influence of the surrounding tree-species diversity on these relationships. Our study suggests that integrated phenotypes allow the variability of leaf phenotypes within the organism and supports that phenotypic integration prevents maladaptive variation.
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Affiliation(s)
- Pablo Castro Sánchez-Bermejo
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle-Wittenberg, Halle (Saale), 06108, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Puschstraße 4, Leipzig, 04103, Germany
| | - Andréa Davrinche
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle-Wittenberg, Halle (Saale), 06108, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Puschstraße 4, Leipzig, 04103, Germany
- Research Centre for Ecological Change (REC), Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, 00014, Finland
| | - Silvia Matesanz
- Área de Biodiversidad y Conservación, Departamento de Biología, Geología, Física y Química inorgánica, ESCET, Universidad Rey Juan Carlos, Móstoles, 28933, Spain
| | - W Stanley Harpole
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle-Wittenberg, Halle (Saale), 06108, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Puschstraße 4, Leipzig, 04103, Germany
- Department of Physiological Diversity, Helmholtz Centre for Environmental Research - UFZ, Leipzig, 04103, Germany
| | - Sylvia Haider
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle-Wittenberg, Halle (Saale), 06108, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Puschstraße 4, Leipzig, 04103, Germany
- Leuphana University of Lüneburg, Institute of Ecology, Lüneburg, 21335, Germany
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Turtureanu PD, Pușcaș M, Podar D, Balázs ZR, Hurdu BI, Novikov A, Renaud J, Saillard A, Bec S, Șuteu D, Băcilă I, Choler P. Extent of intraspecific trait variability in ecologically central and marginal populations of a dominant alpine plant across European mountains. ANNALS OF BOTANY 2023; 132:335-347. [PMID: 37478315 PMCID: PMC10583199 DOI: 10.1093/aob/mcad105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 07/20/2023] [Indexed: 07/23/2023]
Abstract
BACKGROUND AND AIMS Studying trait variability and restricted gene flow between populations of species can reveal species dynamics. Peripheral populations commonly exhibit lower genetic diversity and trait variability due to isolation and ecological marginality, unlike central populations experiencing gene flow and optimal conditions. This study focused on Carex curvula, the dominant species in alpine acidic meadows of European mountain regions. The species is sparser in dry areas such as the Pyrenees and Balkans, compared to the Central-Eastern Alps and Carpathians. We hypothesized that distinct population groups could be identified based on their mean functional trait values and their correlation with the environment; we predicted that ecologically marginal populations would have stronger trait correlations, lower within-population trait variability (intraspecific trait variability, ITV) and lower genetic diversity than populations of optimal habitats. METHODS Sampling was conducted in 34 populations that spanned the entire distribution range of C. curvula. We used hierarchical clustering to identify emergent functional groups of populations, defined by combinations of multiple traits associated with nutrient economy and drought tolerance (e.g. specific leaf area, anatomy). We contrasted the geographical distribution of these groups in relation to environment and genetic structure. We compared pairwise trait relationships, within-population trait variation (ITV) and neutral genetic diversity between groups. KEY RESULTS Our study identified emergent functional groups of populations. Those in the southernmost ranges, specifically the Pyrenees and Balkan region, showed drought-tolerant trait syndromes and correlated with indicators of limited water availability. While we noted a decline in population genetic diversity, we did not observe any significant changes in ITV in ecologically marginal (peripheral) populations. CONCLUSIONS Our research exemplifies the relationship between ecological marginality and geographical peripherality, which in this case study is linked to genetic depauperation but not to reduced ITV. Understanding these relationships is crucial for understanding the biogeographical factors shaping trait variation.
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Affiliation(s)
- Pavel Dan Turtureanu
- A. Borza Botanic Garden, Babeș-Bolyai University, 42 Republicii Street, 400015 Cluj-Napoca, Romania
- Centre for Systems Biology, Biodiversity and Bioresources (3B), Babeș-Bolyai University, 3-5 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Emil G. Racoviță Institute, Babeș-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
| | - Mihai Pușcaș
- A. Borza Botanic Garden, Babeș-Bolyai University, 42 Republicii Street, 400015 Cluj-Napoca, Romania
- Centre for Systems Biology, Biodiversity and Bioresources (3B), Babeș-Bolyai University, 3-5 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Emil G. Racoviță Institute, Babeș-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Faculty of Biology and Geology, Babeș-Bolyai University, 44 Republicii Street, 400015 Cluj-Napoca, Romania
| | - Dorina Podar
- Centre for Systems Biology, Biodiversity and Bioresources (3B), Babeș-Bolyai University, 3-5 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Faculty of Biology and Geology, Babeș-Bolyai University, 44 Republicii Street, 400015 Cluj-Napoca, Romania
| | - Zoltán Robert Balázs
- Centre for Systems Biology, Biodiversity and Bioresources (3B), Babeș-Bolyai University, 3-5 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Faculty of Biology and Geology, Babeș-Bolyai University, 44 Republicii Street, 400015 Cluj-Napoca, Romania
- Doctoral School of Integrative Biology, Babeș-Bolyai University, 1 Kogălniceanu Street, 400084 Cluj-Napoca, Romania
| | - Bogdan-Iuliu Hurdu
- Institute of Biological Research, National Institute of Research and Development for Biological Sciences, 48 Republicii Street, 400015, Cluj-Napoca, Romania
| | - Andriy Novikov
- Department of Biosystematics and Evolution, State Museum of Natural History of the NAS of Ukraine, 18 Teatralna Street, 79008 Lviv, Ukraine
| | - Julien Renaud
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, F-38000 Grenoble, France
| | - Amélie Saillard
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, F-38000 Grenoble, France
| | - Stéphane Bec
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, F-38000 Grenoble, France
| | - Dana Șuteu
- Institute of Biological Research, National Institute of Research and Development for Biological Sciences, 48 Republicii Street, 400015, Cluj-Napoca, Romania
| | - Ioan Băcilă
- Institute of Biological Research, National Institute of Research and Development for Biological Sciences, 48 Republicii Street, 400015, Cluj-Napoca, Romania
| | - Philippe Choler
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, F-38000 Grenoble, France
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Wang C, Duan F, Zhou C, Lu J. The altitudinal distribution characteristics of functional traits reflect the resource allocation strategy of Abies georgei var. smithii in southeast Tibet. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1055195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
To explore the adaptation strategies of the aboveground and underground functional traits of alpine plants along an altitudinal gradient, a typical stand of primitive dark coniferous forests (Abies georgei var. smithii.) in southeastern Tibet was taken as the research object in the present study. PCA and correlation analyses were carried out for different organ functional traits (19 key indicators in total), then RDA analysis was done in conjunction with 12 environmental factors. The variation characteristics of the functional traits of leaves, current-year twigs, trunks and fine roots in 6 continuous altitude gradients and the relationships between functional traits and environmental factors were explored. The results showed that soil organic carbon (SOC) may exert a positive effect on the construction of plant defense tissue via changes in functional traits, altitude (Alt) represents the primary influencing factor of wood density (WD) variation, particulate organic carbon (POC) content mainly affected fine root dry matter (RDWC) content and specific root length (SRL), and total potassium (TK) content was the main factor that affected fine root tissue density (RTD). Leaves, current-year twigs, and fine roots exhibited high production or nutrient acquisition capacity at an altitude of 4,000m and showed strong defense and relatively stable water and nutrient transport capacity. In conclusion, the ecological strategy of Abies georgei var. smithii. in Sejila Mountain was more conservative, and the optimal survival area of Abies georgei var. smithii. was located at 4, 000m on the shady slope of Sejila Mountain. It is of paramount significance for exploring the essence of terrestrial ecosystems and their functional processes in extremely high-altitude environments.
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Duan X, Jia Z, Li J, Wu S. The influencing factors of leaf functional traits variation of Pinus densiflora Sieb. et Zucc. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2022.e02177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Vicente E, Didion-Gency M, Morcillo L, Morin X, Vilagrosa A, Grossiord C. Aridity and cold temperatures drive divergent adjustments of European beech xylem anatomy, hydraulics and leaf physiological traits. TREE PHYSIOLOGY 2022; 42:1720-1735. [PMID: 35285500 DOI: 10.1093/treephys/tpac029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
Understanding plant trait coordination and variance across climatic gradients is critical for assessing forests' adaptive potential to climate change. We measured 11 hydraulic, anatomical and leaf-level physiological traits in European beech (Fagus sylvatica L.) along a moisture and temperature gradient in the French Alps. We assessed how traits covaried, and how their population-level variances shifted along the gradient. The intrapopulation variances of vessel size and xylem-specific conductivity reduced in colder locations as narrow vessels were observed in response to low temperature. This decreased individual-level water transport capacity compared with the warmer and more xeric sites. Conversely, the maximum stomatal conductance and Huber value variances were constrained in the arid and warm locations, where trees showed restricted gas exchange and higher xylem-specific conductivity. The populations growing under drier and warmer conditions presented wide variance for the xylem anatomical and hydraulic traits. Our results suggest that short-term physiological acclimation to raising aridity and heat in southern beech populations may occur mainly at the leaf level. Furthermore, the wide variance of the xylem anatomical and hydraulic traits at these sites may be advantageous since more heterogeneous hydraulic conductivity could imply populations' greater tree-tree complementarity and resilience against climatic variability. Our study highlights that both intrapopulation trait variance and trait network analysis are key approaches for understanding species adaptation and the acclimation potential to a shifting environment.
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Affiliation(s)
- Eduardo Vicente
- Department of Ecology, Faculty of Sciences, IMEM Ramón Margalef, University of Alicante, C. San Vicente del Raspeig, s/n, Alicante 03080, Spain
- CEAM Foundation, Joint Research Unit University of Alicante-CEAM, Department of Ecology, University of Alicante, PO Box 99, C. San Vicente del Raspeig, s/n, Alicante 03080, Spain
| | - Margaux Didion-Gency
- Ecosystem Ecology, Forest Dynamics Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, Zürcherstrasse 111, Birmensdorf 8903, Switzerland
| | - Luna Morcillo
- CEAM Foundation, Joint Research Unit University of Alicante-CEAM, Department of Ecology, University of Alicante, PO Box 99, C. San Vicente del Raspeig, s/n, Alicante 03080, Spain
| | - Xavier Morin
- CEFE UMR 5175 (CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, IRD), 1919 Route de Mende, Montpellier Cedex 5 F-34293, France
| | - Alberto Vilagrosa
- CEAM Foundation, Joint Research Unit University of Alicante-CEAM, Department of Ecology, University of Alicante, PO Box 99, C. San Vicente del Raspeig, s/n, Alicante 03080, Spain
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, PO box 96, Lausanne CH-1015, Switzerland
- Functional Plant Ecology, Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, PO box 96, Lausanne CH-1015, Switzerland
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Matesanz S, Blanco-Sánchez M, Ramos-Muñoz M, de la Cruz M, Benavides R, Escudero A. Phenotypic integration does not constrain phenotypic plasticity: differential plasticity of traits is associated to their integration across environments. THE NEW PHYTOLOGIST 2021; 231:2359-2370. [PMID: 34097309 DOI: 10.1111/nph.17536] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 05/25/2021] [Indexed: 06/12/2023]
Abstract
Understanding constraints to phenotypic plasticity is key given its role on the response of organisms to environmental change. It has been suggested that phenotypic integration, the structure of trait covariation, could limit trait plasticity. However, the relationship between plasticity and integration is far from resolved. Using a database of functional plasticity to drought of a Mediterranean shrub that included 20 ecophysiological traits, we assessed environmentally-induced changes in phenotypic integration and whether integration constrained the expression of plasticity, accounting for the within-environment phenotypic variation of traits. Furthermore, we provide the first test of the association between differential trait plasticity and trait integration across an optimum and a stressful environment. Phenotypic plasticity was positively associated with phenotypic integration in both environments, but this relationship was lost when phenotypic variation was considered. The similarity in the plastic response of two traits predicted their integration across environments, with integrated traits having more similar plasticity. Such variation in the plasticity of traits partly explained the lower phenotypic integration found in the stressful environment. We found no evidence that integration may constitute an internal constraint to plasticity. Rather, we present the first empirical demonstration that differences in plastic responses may involve a major reorganization of the relationships among traits, and challenge the notion that stress generally induces a tighter phenotype.
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Affiliation(s)
- Silvia Matesanz
- Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, C/Tulipán, s/n, Móstoles, 28933, Spain
| | - Mario Blanco-Sánchez
- Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, C/Tulipán, s/n, Móstoles, 28933, Spain
| | - Marina Ramos-Muñoz
- Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, C/Tulipán, s/n, Móstoles, 28933, Spain
| | - Marcelino de la Cruz
- Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, C/Tulipán, s/n, Móstoles, 28933, Spain
| | - Raquel Benavides
- Centro de Estudos Florestais, ISA, Universidade de Lisboa, Tapada da Ajuda, Lisboa, 1349-017, Portugal
- Departamento de Biogeografía y Cambio Global, Museo Nacional de Ciencias Naturales, CSIC, C/José Gutiérrez Abascal 2, Madrid, 28006, Spain
| | - Adrián Escudero
- Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, C/Tulipán, s/n, Móstoles, 28933, Spain
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García-Cervigón AI, García-López MA, Pistón N, Pugnaire FI, Olano JM. Co-ordination between xylem anatomy, plant architecture and leaf functional traits in response to abiotic and biotic drivers in a nurse cushion plant. ANNALS OF BOTANY 2021; 127:919-929. [PMID: 33640955 PMCID: PMC8225275 DOI: 10.1093/aob/mcab036] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/24/2021] [Indexed: 05/15/2023]
Abstract
BACKGROUND AND AIMS Plants in dry Mediterranean mountains experience a double climatic stress: at low elevations, high temperatures coincide with water shortage during summer, while at high elevations temperature decreases and water availability increases. Cushion plants often act as nurses by improving the microclimate underneath their canopies, hosting beneficiary species that may reciprocally modify their benefactors' microenvironment. We assess how the nurse cushion plant Arenaria tetraquetra subsp. amabilis adjusts its hydraulic system to face these complex abiotic and biotic constraints. METHODS We evaluated intra-specific variation and co-ordination of stem xylem anatomy, leaf functional traits and plant architecture in response to elevation, aspect and the presence of beneficiary species in four A. tetraquetra subsp. amabilis populations in the Sierra Nevada mountains, southern Spain. KEY RESULTS Xylem anatomical and plant architectural traits were the most responsive to environmental conditions, showing the highest mutual co-ordination. Cushions were more compact and had smaller, more isolated conductive vessels in the southern than in the northern aspect, which allow minimization of the negative impacts of more intense drought. Only vessel size, leaf mass per area and terminal branch length varied with elevation. Nurse cushions co-ordinated plant architecture and xylem traits, having higher canopy compactness, fewer leaves per branch and fewer, more isolated vessels than non-nurse cushions, which reflects the negative effects of beneficiary plants on nurse water status. In non-nurse cushions, plant architecture co-ordinated with leaf traits instead. The interacting effects of aspect and elevation on xylem traits showed that stress due to frost at high elevation constrained xylem anatomy in the north, whereas stress due to drought had a parallel effect in the south. CONCLUSIONS Trait co-ordination was weaker under more demanding environmental conditions, which agrees with the hypothesis that trait independence allows plants to better optimize different functions, probably entailing higher adjustment potential against future environmental changes.
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Affiliation(s)
- Ana I García-Cervigón
- Department of Biology and Geology, Physics and Inorganic Chemistry, Rey Juan Carlos University, c/Tulipán s/n, Móstoles, Spain
- For correspondence. E-mail
| | | | - Nuria Pistón
- Department of Ecology, Center for Health Sciences, Federal University of Rio de Janeiro, Av. Carlos Chagas Filho, Rio de Janeiro – RJ, Brazil
| | - Francisco I Pugnaire
- Estación Experimental de Zonas Áridas, EEZA-CSIC, Ctra. de Sacramento s/n, La Cañada, Almería, Spain
| | - José Miguel Olano
- iuFOR-EiFAB, University of Valladolid, Campus Duques de Soria s/n, Soria, Spain
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