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Piper FI, Fajardo A. Carbon stress causes earlier budbreak in shade-tolerant species and delays it in shade-intolerant species. AMERICAN JOURNAL OF BOTANY 2023; 110:1-11. [PMID: 36696584 DOI: 10.1002/ajb2.16129] [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: 07/10/2022] [Revised: 12/16/2022] [Accepted: 12/16/2022] [Indexed: 05/11/2023]
Abstract
PREMISE Climate change may lead to C stress (negative C balance) in trees. Because nonstructural carbohydrates (NSC) are required during metabolic reactivation in the spring, C stress might delay budbreak timing. This effect is expected to be greater in shade-intolerant than in shade-tolerant species, owing to the faster C economy in the shade-intolerant. METHODS We experimentally induced C stress in saplings of six temperate tree species that differed in their light requirements by exposing them to either full light or shade from summer to spring, then recorded the date of first budbreak for the individuals. Because the levels of C reserves that represent effective C stress may differ among species, we estimated the degree of C stress by recording survival during the experiment and measuring whole-sapling NSC concentrations after budbreak. RESULTS Shade reduced NSC concentrations and increased the sugar fraction in the NSC in all species. In the shade, shade-intolerant species had higher mortality and generally lower NSC concentrations than the shade-tolerant species, indicating a trend for more severe C stress in species with faster C economy. In shade-intolerant species, budbreak started earlier and proceeded faster in full light than in shade, but in shade-tolerant species budbreak was delayed in full light. The effects of the light environments on budbreak were not greater in shade-intolerant than in shade-tolerant species. CONCLUSIONS Our study reveals a correspondence between budbreak responses to light and the light requirements of the species. This finding confirms that C metabolism has a significant role in triggering budbreak and demonstrates that whether C stress accelerates or delays budbreak depends on the species' light requirements.
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Affiliation(s)
- Frida I Piper
- Instituto de Ciencias Biológicas (ICB), Universidad de Talca, Campus Lircay, Talca, 3460000, Chile
- Instituto de Ecología y Biodiversidad (IEB), Chile. Victoria 631, Barrio Universitario, Concepción, Chile
- Millenium Nucleus of Patagonian Limit of Life (LiLi), Universidad de Talca, Chile
| | - Alex Fajardo
- Instituto de Investigación Interdisciplinaria (I3), Vicerrectoría Académica, Universidad de Talca, Campus Lircay, Talca, 3460000, Chile
- Instituto de Ecología y Biodiversidad (IEB), Chile. Victoria 631, Barrio Universitario, Concepción, Chile
- Millenium Nucleus of Patagonian Limit of Life (LiLi), Universidad de Talca, Chile
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Liu X, Du Y, Ren Y, Wang S, Wang Y, Li Z, Wang W. New insights into the cortex-to-stele ratio show it to effectively indicate inter- and intraspecific function in the absorptive roots of temperate trees. FRONTIERS IN PLANT SCIENCE 2023; 14:1061503. [PMID: 36743504 PMCID: PMC9895863 DOI: 10.3389/fpls.2023.1061503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 01/10/2023] [Indexed: 06/18/2023]
Abstract
The cortex-to-stele ratio (CSR), as it increases from thin- to thick-root species in angiosperms, is theorised to effectively reflect a compensation for the 'lag' of absorption behind transportation. But it is still not known if this compensatory effect exists in gymnosperm species or governs root structure and function within species. Here, anatomical, morphological, and tissue chemical traits of absorptive roots were measured in three temperate angiosperm and three gymnosperm species. Differences in the CSR and the above functional traits, as well as their intraspecific associations, were analyzed and then compared between angiosperms and gymnosperms. At the intraspecific level, the CSR decreased with increasing root order for all species. The expected functional indication of the CSR was consistent with decreases in specific root length (SRL) and N concentration and increases in the C to N ratio (C:N ratio) and the number of and total cross-sectional area of conduits with increasing root order, demonstrating that the CSR indicates the strength of absorption and transportation at the intraspecific level, but intraspecific changes are due to root development rather than the compensatory effect. These trends resulted in significant intraspecific associations between the CSR and SRL (R 2 = 0.36 ~ 0.80), N concentration (R 2 = 0.48 ~ 0.93), the C:N ratio (R 2 = 0.47 ~ 0.91), and the number of (R 2 = 0.21 ~ 0.78) and total cross-sectional area (R 2 = 0.29 ~ 0.72) of conduits in each species (p< 0.05). The overall mean CSR of absorptive roots in angiosperms was four times greater than in gymnosperms, and in angiosperms, the CSR was significantly higher in thick- than in thin-rooted species, whereas in gymnosperms, the interspecific differences were not significant (p > 0.05). This suggests that the compensation for the lag of absorption via cortex thickness regulation was stronger in three angiosperm species than in three gymnosperm species. In addition, there was poor concordance between angiosperms and gymnosperms in the relationships between CSRs and anatomical, morphological, and tissue chemical traits. However, these gymnosperm species show a more stable intraspecific functional association compared to three angiosperm species. In general, absorptive root CSRs could manifest complex strategies in resource acquisition for trees at both intra- and interspecific levels.
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Affiliation(s)
- Xiangjuan Liu
- Key Laboratory of Germplasm Resources of Tropical Special Ornamental Plants of Hainan Province, College of Forestry, Hainan University, Haikou, China
| | - Yanjun Du
- Key Laboratory of Germplasm Resources of Tropical Special Ornamental Plants of Hainan Province, College of Forestry, Hainan University, Haikou, China
| | - Yin Ren
- Key Laboratory of Germplasm Resources of Tropical Special Ornamental Plants of Hainan Province, College of Forestry, Hainan University, Haikou, China
| | - Siyuan Wang
- School of Forestry, Northeast Forestry University, Harbin, China
| | - Yan Wang
- Taishan Forest Ecosystem Research Station of State Forestry Administration, State Forestry and Grassland Administration Key Laboratory of Silviculture in downstream areas of the Yellow River, College of Forestry, Shandong Agricultural University, Taian, China
| | - Zhongyue Li
- Taishan Forest Ecosystem Research Station of State Forestry Administration, State Forestry and Grassland Administration Key Laboratory of Silviculture in downstream areas of the Yellow River, College of Forestry, Shandong Agricultural University, Taian, China
| | - Wenna Wang
- Key Laboratory of Germplasm Resources of Tropical Special Ornamental Plants of Hainan Province, College of Forestry, Hainan University, Haikou, China
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Piper FI, Moreno‐Meynard P, Fajardo A. Non‐structural carbohydrates predict survival in saplings of temperate trees under carbon stress. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Frida I. Piper
- Instituto de Ciencias Biológicas (ICB), Universidad de Talca, Campus Lircay 3460000 Talca Chile
- Institute of Ecology and Biodiversity (IEB), Barrio Universitario S/N Concepción Chile
| | - Paulo Moreno‐Meynard
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP), Moraleda 16 Coyhaique Chile
| | - Alex Fajardo
- Institute of Ecology and Biodiversity (IEB), Barrio Universitario S/N Concepción Chile
- Instituto de Investigación Interdisciplinaria (I3), Universidad de Talca Chile
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Perera-Castro AV, González-Rodríguez ÁM, Fernández-Marín B. When time is not of the essence: constraints to the carbon balance of bryophytes. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4562-4575. [PMID: 35298628 DOI: 10.1093/jxb/erac104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 03/10/2022] [Indexed: 06/14/2023]
Abstract
The data available so far indicate that the photosynthetic and relative growth rates of bryophytes are 10% of those reported for tracheophytes. By examining the existing literature and reanalysing data published in over 100 studies, this review examines the ecophysiological, biochemical, and structural reasons behind this phenomenon. The limiting Rubisco content and surface for gas exchange are the internal factors that can explain the low photosynthetic and growth rates of bryophytes. The role of the thicker cell walls of bryophytes in limiting CO2 diffusion is unclear, due to the current uncertainties regarding their porosity and permeability to CO2. From this review, it is also evident that, despite bryophytes having low photosynthetic rates, their positive carbon balance is tightly related to their capacity to deal with extreme conditions. Contributing factors include their capacity to deal with large daily temperature oscillations, and their capacity to delay the cessation of photosynthesis under water deficit (or to tolerate desiccation in extreme situations). Although further studies on bryophytes are needed before more solid conclusions can be drawn, it seems that their success relies on their remarkable tolerance to a highly variable environment, possibly at the expense of their maximum photosynthetic rate.
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Affiliation(s)
- Alicia V Perera-Castro
- Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna, 38200 La Laguna, Canary Islands, Spain
| | - Águeda M González-Rodríguez
- Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna, 38200 La Laguna, Canary Islands, Spain
| | - Beatriz Fernández-Marín
- Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna, 38200 La Laguna, Canary Islands, Spain
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Zhang G, Mao Z, Fortunel C, Martínez-Vilalta J, Viennois G, Maillard P, Stokes A. Parenchyma fractions drive the storage capacity of nonstructural carbohydrates across a broad range of tree species. AMERICAN JOURNAL OF BOTANY 2022; 109:535-549. [PMID: 35266560 DOI: 10.1002/ajb2.1838] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 02/17/2022] [Indexed: 06/14/2023]
Abstract
PREMISE Nonstructural carbohydrates (NSCs) play a key role in tree performance and functioning and are stored in radial and axial parenchyma (RAP) cells. Whether this relationship is altered among species and climates or is linked to functional traits describing xylem structure (wood density) and tree stature is not known. METHODS In a systematic review, we collated data for NSC content and the proportion of RAP in stems for 68 tree species. To examine the relationships of NSCs and RAP with climatic factors and other functional traits, we also collected climatic data at each tree's location, as well as wood density and maximum height. A phylogenetic tree was constructed to examine the influence of species' evolutionary relationships on the associations among NSCs, RAP, and functional traits. RESULTS Across all 68 tree species, NSCs were positively correlated with RAP and mean annual temperature, but relationships were only weakly significant in temperate species and angiosperms. When separating RAP into radial parenchyma (RP) and axial parenchyma (AP), both NSCs and wood density were positively correlated with RP but not with AP. Wood in taller trees was less dense and had lower RAP than in shorter trees, but height was not related to NSCs. CONCLUSIONS In trees, NSCs are stored mostly in the RP fraction, which has a larger surface area in warmer climates. Additionally, NSCs were only weakly linked to wood density and tree height. Our analysis of evolutionary relationships demonstrated that RAP fractions and NSC content were always closely related across all 68 tree species, suggesting that RAP can act as a reliable proxy for potential NSC storage capacity in tree stems.
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Affiliation(s)
- Guangqi Zhang
- AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Zhun Mao
- AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Claire Fortunel
- AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Jordi Martínez-Vilalta
- CREAF, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Universitat Autònoma Barcelona, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - Gaëlle Viennois
- AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Pascale Maillard
- SILVA, INRAE, Université de Lorraine, Agroparistech, Centre de Recherche Grand-Est Nancy, 54280 Champenoux, France
| | - Alexia Stokes
- AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
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Löiez S, Piper FI. Phenology explains different storage remobilization in two congeneric temperate tree species with contrasting leaf habit. TREE PHYSIOLOGY 2022; 42:501-512. [PMID: 34542156 DOI: 10.1093/treephys/tpab124] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 08/02/2021] [Accepted: 09/08/2021] [Indexed: 06/13/2023]
Abstract
The dependence of trees on carbon and nutrient storage is critical to predicting the forest vulnerability under climate change, but whether evergreen and deciduous species differ in their use and allocation of stored resources during spring phenology is unclear. Using a high temporal resolution, we evaluated the role of spring phenology and shoot growth as determinants of the carbon and nutrient storage dynamics in contrasting leaf habits. We recorded the phenology and shoot elongation and determined the concentrations of total non-structural carbohydrates (NSCs), starch, soluble carbohydrates, nitrogen (N) and phosphorus (P) in buds, expanding shoots and previously formed shoots of two sympatric Nothofagus species with contrasting leaf habit. Species reached similar shoot lengths, though shoot expansion started 35 days earlier and lasted c. 40 days more in the deciduous species. Thus, although the deciduous species had a relatively constant shoot growth rate, the evergreen species experienced a conspicuous growth peak for c. 20 days. In the evergreen species, the greatest decreases in NSC concentrations of previously formed shoots and leaves coincided with the maximum shoot expansion rate and fruit filling, with minimums of 63 and 65% relative to values at bud dormancy, respectively. In contrast, minimum NSC concentrations of the previously formed shoots of the deciduous species were only 73% and occurred prior to the initiation of shoot expansion. Bud N and P concentrations increased during budbreak, whereas previously formed shoots generally did not decrease their nutrient concentrations. Late spring phenology and overlapping of phenophases contributed to the greater dependence on storage of proximal tissues in the studied evergreen compared with deciduous species, suggesting that phenology is a key determinant of the contrasting patterns of storage use in evergreen and deciduous species.
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Affiliation(s)
- Sidonie Löiez
- Agrocampus Ouest, 65, rue de Saint-Brieuc, CS 84215, Rennes Cedex 35042, France
| | - Frida I Piper
- Instituto de Investigación Interdisciplinario (I3), Universidad de Talca, Campus Lircay, Talca 3460000, Chile
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Dewar R, Hölttä T, Salmon Y. Exploring optimal stomatal control under alternative hypotheses for the regulation of plant sources and sinks. THE NEW PHYTOLOGIST 2022; 233:639-654. [PMID: 34637543 DOI: 10.1111/nph.17795] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 09/19/2021] [Indexed: 06/13/2023]
Abstract
Experimental evidence that nonstomatal limitations to photosynthesis (NSLs) correlate with leaf sugar and/or leaf water status suggests the possibility that stomata adjust to maximise photosynthesis through a trade-off between leaf CO2 supply and NSLs, potentially involving source-sink interactions. However, the mechanisms regulating NSLs and sink strength, as well as their implications for stomatal control, remain uncertain. We used an analytically solvable model to explore optimal stomatal control under alternative hypotheses for source and sink regulation. We assumed that either leaf sugar concentration or leaf water potential regulates NSLs, and that either phloem turgor pressure or phloem sugar concentration regulates sink phloem unloading. All hypotheses led to realistic stomatal responses to light, CO2 and air humidity, including conservative behaviour for the intercellular-to-atmospheric CO2 concentration ratio. Sugar-regulated and water-regulated NSLs are distinguished by the presence/absence of a stomatal closure response to changing sink strength. Turgor-regulated and sugar-regulated phloem unloading are distinguished by the presence/absence of stomatal closure under drought and avoidance/occurrence of negative phloem turgor. Results from girdling and drought experiments on Pinus sylvestris, Betula pendula, Populus tremula and Picea abies saplings are consistent with optimal stomatal control under sugar-regulated NSLs and turgor-regulated unloading. Our analytical results provide a simple representation of stomatal responses to above-ground and below-ground environmental factors and sink activity.
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Affiliation(s)
- Roderick Dewar
- Faculty of Science, Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, PO Box 68, Gustaf Hällströmin katu 2b, Helsinki, 00014, Finland
- Plant Sciences Division, Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Teemu Hölttä
- Faculty of Agriculture and Forestry, Institute for Atmospheric and Earth System Research/Forest Sciences, University of Helsinki, PO Box 27, Latokartanonkaari 7, Helsinki, 00014, Finland
| | - Yann Salmon
- Faculty of Science, Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, PO Box 68, Gustaf Hällströmin katu 2b, Helsinki, 00014, Finland
- Faculty of Agriculture and Forestry, Institute for Atmospheric and Earth System Research/Forest Sciences, University of Helsinki, PO Box 27, Latokartanonkaari 7, Helsinki, 00014, Finland
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Piper FI. Putting non-structural compounds on the map of plant life history strategies: a commentary on Schoonmaker et al. TREE PHYSIOLOGY 2021; 41:1559-1562. [PMID: 34274975 DOI: 10.1093/treephys/tpab088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Frida I Piper
- Instituto de Investigación Interdisciplinario (I3), Universidad de Talca, Campus Lircay, Talca 3460000, Chile
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Wang L, Liu J, Shen Y, Pu R, Hou M, Wei Q, Zhang X, Li G, Ren H, Wu G. Brassinosteroids synthesised by CYP85A/A1 but not CYP85A2 function via a BRI1-like receptor but not via BRI1 in Picea abies. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:1748-1763. [PMID: 33247718 DOI: 10.1093/jxb/eraa557] [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: 03/06/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
Brassinosteroids (BRs) are essential plant hormones. In angiosperms, brassinolide and castasterone, the first and second most active BRs, respectively, are synthesised by CYP85A2 and CYP85A/A1, respectively. BRs in angiosperms function through an essential receptor, BR Insensitive 1 (BRI1). In addition, some angiosperms also have non-essential BRI1-like 1/3 (BRL1/3). In conifers, BRs promote seed germination under drought stress; however, how BRs function in gymnosperms is unknown. In this study, we performed functional complementation of BR biosynthesis and receptor genes from Picea abies with respective Arabidopsis mutants. We found that P. abies possessed functional PaCYP85A and PaBRL1 but not PaCYP85A2 or PaBRI1, and this results in weak BR signaling, and both PaCYP85A and PaBRL1 were abundantly expressed. However, neither BR treatment of P. abies seedlings nor expression of PaBRL1 in the Arabidopsis Atbri1 mutant promoted plant height, despite the fact that BR-responsive genes were activated. Importantly, chimeric AtBRI1 replaced with the BR-binding domain of PaBRL1 complemented the Atbri1 phenotypes. Furthermore, PaBRL1 had less kinase activity than BRI1 in vitro. Overall, P. abies had weak but still active BR signaling, explaining aspects of its slow growth and high stress tolerance. Our study sheds light on the functional and evolutionary significance of distinct BR signaling that is independent of BRI1 and brassinolide.
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Affiliation(s)
- Li Wang
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Jing Liu
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Yitong Shen
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Ruolan Pu
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Meiying Hou
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Qiang Wei
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Xinzhen Zhang
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Guishuang Li
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Hongyan Ren
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
| | - Guang Wu
- College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi Province, P.R. China
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10
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Piper FI. Decoupling between growth rate and storage remobilization in broadleaf temperate tree species. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13552] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Frida I. Piper
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP) Coyhaique Chile
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Piper FI, Gundale MJ, Fuenzalida T, Fajardo A. Herbivore resistance in congeneric and sympatric Nothofagus species is not related to leaf habit. AMERICAN JOURNAL OF BOTANY 2019; 106:788-797. [PMID: 31131459 DOI: 10.1002/ajb2.1293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 03/26/2019] [Indexed: 06/09/2023]
Abstract
PREMISE Two fundamental hypotheses on herbivore resistance and leaf habit are the resource availability hypothesis (RAH) and the carbon-nutrient balance hypothesis (CNBH). The RAH predicts higher constitutive resistance by evergreens, and the CNBH predicts higher induced resistance by deciduous species. Although support for these hypotheses is mixed, they have rarely been examined in congeneric species. METHODS We compared leaf constitutive and induced resistance (as leaf polyphenol and tannin concentrations, and as damage level in non-choice experiments) and leaf traits associated with herbivory of coexisting Nothofagus species using (1) a defoliation experiment and (2) natural defoliation caused by an outbreak of a common defoliator of Nothofagus species. RESULTS In the defoliation experiment, polyphenol and tannin concentrations were similar between deciduous and evergreen species; regardless of leaf habit, polyphenols increased in response to defoliation. In the natural defoliation survey, N. pumilio (deciduous) had significantly higher herbivory, lower carbon/nitrogen ratio and leaf mass per area, and higher nitrogen and phosphorus concentrations than N. betuloides (evergreen); N. antarctica (deciduous) had intermediate values. Polyphenol concentrations and herbivore resistance indicated by the non-choice experiment were lower in N. pumilio than in N. antarctica and N. betuloides, which had similar values. CONCLUSIONS Higher herbivory in N. pumilio was associated with a higher nutritional value and a lower level of leaf carbon-based defenses compared to both the evergreen and the other deciduous species, indicating that herbivore resistance in Nothofagus species cannot be attributed to only leaf habit as predicted by the RAH or CNBH.
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Affiliation(s)
- Frida I Piper
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP), Moraleda 16, Coyhaique, 5951601, Chile
| | - Michael J Gundale
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | - Tomás Fuenzalida
- Plant Science Division, Research School of Biology, The Australian National University, Acton, ACT, 2601, Australia
| | - Alex Fajardo
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP), Moraleda 16, Coyhaique, 5951601, Chile
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