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Chang H, Chen YT, Huang HE, Ger MJ. Overexpressing plant ferredoxin-like protein enhances photosynthetic efficiency and carbohydrates accumulation in Phalaenopsis. Transgenic Res 2023; 32:547-560. [PMID: 37851307 DOI: 10.1007/s11248-023-00370-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 10/04/2023] [Indexed: 10/19/2023]
Abstract
Crassulacean acid metabolism (CAM) is one of three major models of carbon dioxide assimilation pathway with better water-use efficiency and slower photosynthetic efficiency in photosynthesis. Previous studies indicated that the gene of sweet pepper plant ferredoxin-like protein (PFLP) shows high homology to the ferredoxin-1(Fd-1) family that belongs to photosynthetic type Fd and involves in photosystem I. It is speculated that overexpressing pflp in the transgenic plant may enhance photosynthetic efficiency through the electron transport chain (ETC). To reveal the function of PFLP in photosynthetic efficiency, pflp transgenic Phalaenopsis, a CAM plant, was generated to analyze photosynthetic markers. Transgenic plants exhibited 1.2-folds of electron transport rate than that of wild type (WT), and higher CO2 assimilation rates up to 1.6 and 1.5-folds samples at 4 pm and 10 pm respectively. Enzyme activity of phosphoenolpyruvate carboxylase (PEPC) was increased to 5.9-folds in Phase III, and NAD+-linked malic enzyme (NAD+-ME) activity increased 1.4-folds in Phase IV in transgenic plants. The photosynthesis products were analyzed between transgenic plants and WT. Soluble sugars contents such as glucose, fructose, and sucrose were found to significantly increase to 1.2, 1.8, and 1.3-folds higher in transgenic plants. The starch grains were also accumulated up to 1.4-folds in transgenic plants than that of WT. These results indicated that overexpressing pflp in transgenic plants increases carbohydrates accumulation by enhancing electron transport flow during photosynthesis. This is the first evidence for the PFLP function in CAM plants. Taken altogether, we suggest that pflp is an applicable gene for agriculture application that enhances electron transport chain efficiency during photosynthesis.
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Affiliation(s)
- Hsiang Chang
- Department of Biotechnology and Pharmaceutical Technology, Yuanpei University of Medical Technology, Hsinchu, 30015, Taiwan
| | - Yen-Ting Chen
- Institute of Biotechnology, National University of Kaohsiung, Kaohsiung, 81148, Taiwan
| | - Hsiang-En Huang
- Department of Life Sciences, National Taitung University, Taitung, 95002, Taiwan
| | - Mang-Jye Ger
- Department of Life Sciences, National University of Kaohsiung, Kaohsiung, 81148, Taiwan.
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Wang W, Yuan L, Zhou J, Zhu X, Liao Z, Yin L, Li W, Jiang HS. Inorganic carbon utilization: A target of silver nanoparticle toxicity on a submerged macrophyte. Environ Pollut 2023; 318:120906. [PMID: 36549447 DOI: 10.1016/j.envpol.2022.120906] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/12/2022] [Accepted: 12/17/2022] [Indexed: 06/17/2023]
Abstract
Submerged macrophytes play an important role in the global carbon cycle through diversified pathways of inorganic carbon (Ci) utilization distinct from terrestrial plants. However, the effects of silver nanoparticles (AgNPs), an emerging contaminant, were unknown on the Ci utilization of submerged macrophytes. In Ottelia alismoides, the only known submerged macrophyte with three pathways of Ci utilization, before absorption, AgNPs inhibited the external carbonic anhydrase activity thus reducing the capacity of the plant to use HCO3-. After entering the plant, AgNPs mainly aggregated at the cell wall and in the chloroplast. The internalized AgNPs inhibited ribulose 1,5-bisphosphate carboxylase-oxygenase (Rubisco) activity blocking CO2 fixation and disturbed C4 and crassulacean acid metabolism (CAM) by inhibiting phosphoenolpyruvate carboxylase (PEPC), pyruvate phosphate dikinase (PPDK), and NAD-dependent malic enzyme (NAD-ME) activities to alter intracellular malate biosynthesis and decarboxylation. Overall, our findings indicate that the Ci utilization of the submerged macrophyte is a target of AgNPs toxicity that might affect the carbon cycle in aquatic systems.
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Affiliation(s)
- Wanwan Wang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; College of Horticulture and Gardening, Yangtze University, Jingzhou, 434025, China
| | - Longyi Yuan
- College of Horticulture and Gardening, Yangtze University, Jingzhou, 434025, China
| | - Jingzhe Zhou
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Xi Zhu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, School of Life Sciences, Hainan University, HaiKou, 570228, China
| | - Zuying Liao
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Liyan Yin
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, School of Life Sciences, Hainan University, HaiKou, 570228, China
| | - Wei Li
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Hong Sheng Jiang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
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Ullah H, Treesubsuntorn C, Thiravetyan P. Enhancing mixed toluene and formaldehyde pollutant removal by Zamioculcas zamiifolia combined with Sansevieria trifasciata and its CO 2 emission. Environ Sci Pollut Res Int 2021; 28:538-546. [PMID: 32812163 DOI: 10.1007/s11356-020-10342-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 07/30/2020] [Indexed: 06/11/2023]
Abstract
Indoor air pollutants comprise both polar and non-polar volatile organic compounds (VOCs). Indoor potted plants are well known for their innate ability to improve indoor air quality (IAQ) by detoxification of indoor air pollutants. In this study, a combination of two different plant species comprising a C3 plant (Zamioculcas zamiifolia) and a crassulacean acid metabolism (CAM) plant (Sansevieria trifasciata) was used to remove polar and non-polar VOCs and minimize CO2 emission from the chamber. Z. zamiifolia and S. trifasciata, when combined, were able to remove more than 95% of pollutants within 48 h and could do so for six consecutive pollutant's exposure cycles. The CO2 concentration was reduced from 410 down to 160 ppm inside the chamber. Our results showed that using plant growth medium rather than soil had a positive effect on decreasing CO2. We also re-affirmed the role of formaldehyde dehydrogenase in the detoxification and metabolism of formaldehyde and that exposure of plants to pollutants enhances the activity of this enzyme in the shoots of both Z. zamiifolia and S. trifasciata. Overall, a mixed plant of Z. zamiifolia and S. trifasciata was more efficient at removing mixed pollutants and reducing CO2 than individual plants.
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Affiliation(s)
- Haseeb Ullah
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Chairat Treesubsuntorn
- Pilot Plant Development and Training Institute, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Paitip Thiravetyan
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand.
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Huang WM, Shao H, Zhou SN, Zhou Q, Fu WL, Zhang T, Jiang HS, Li W, Gontero B, Maberly SC. Different CO 2 acclimation strategies in juvenile and mature leaves of Ottelia alismoides. Photosynth Res 2018; 138:219-232. [PMID: 30078074 DOI: 10.1007/s11120-018-0568-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 07/28/2018] [Indexed: 06/08/2023]
Abstract
The freshwater macrophyte, Ottelia alismoides, is a bicarbonate user performing C4 photosynthesis in the light, and crassulacean acid metabolism (CAM) when acclimated to low CO2. The regulation of the three mechanisms by CO2 concentration was studied in juvenile and mature leaves. For mature leaves, the ratios of phosphoenolpyruvate carboxylase (PEPC) to ribulose-bisphosphate carboxylase/oxygenase (Rubisco) are in the range of that of C4 plants regardless of CO2 concentration (1.5-2.5 at low CO2, 1.8-3.4 at high CO2). In contrast, results for juvenile leaves suggest that C4 is facultative and only present under low CO2. pH-drift experiments showed that both juvenile and mature leaves can use bicarbonate irrespective of CO2 concentration, but mature leaves have a significantly greater carbon-extracting ability than juvenile leaves at low CO2. At high CO2, neither juvenile nor mature leaves perform CAM as indicated by lack of diurnal acid fluctuation. However, CAM was present at low CO2, though the fluctuation of titratable acidity in juvenile leaves (15-17 µequiv g-1 FW) was slightly but significantly lower than in mature leaves (19-25 µequiv g-1 FW), implying that the capacity to perform CAM increases as leaves mature. The increased CAM activity is associated with elevated PEPC activity and large diel changes in starch content. These results show that in O. alismoides, carbon-dioxide concentrating mechanisms are more effective in mature compared to juvenile leaves, and C4 is facultative in juvenile leaves but constitutive in mature leaves.
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Affiliation(s)
- Wen Min Huang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Hui Shao
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Aix Marseille Univ, CNRS, BIP, UMR 7281, 31 Chemin Joseph Aiguier, CS70071, 13402, Marseille Cedex 09, France
| | - Si Ning Zhou
- Sino-Danish Center, The University of Chinese Academy of Sciences, Beijing, 101400, China
| | - Qin Zhou
- School of Resources and Environmental Science, Hubei University, Wuhan, 430074, China
| | - Wen Long Fu
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Ting Zhang
- School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Hong Sheng Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Brigitte Gontero
- Aix Marseille Univ, CNRS, BIP, UMR 7281, 31 Chemin Joseph Aiguier, CS70071, 13402, Marseille Cedex 09, France.
| | - Stephen C Maberly
- Lake Ecosystems Group, Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Lancaster, Bailrigg, LA1 4AP, UK.
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Holtum JAM, Hancock LP, Edwards EJ, Winter K. Facultative CAM photosynthesis (crassulacean acid metabolism) in four species of Calandrinia, ephemeral succulents of arid Australia. Photosynth Res 2017; 134:17-25. [PMID: 28871459 DOI: 10.1007/s11120-017-0359-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/14/2017] [Indexed: 06/07/2023]
Abstract
Crassulacean acid metabolism (CAM) was demonstrated in four small endemic Australian terrestrial succulents from the genus Calandrinia (Montiaceae) viz. C. creethiae, C. pentavalvis, C. quadrivalvis and C. reticulata. CAM was substantiated by measurements of CO2 gas-exchange and nocturnal acidification. In all species, the expression of CAM was overwhelmingly facultative in that nocturnal H+ accumulation was greatest in droughted plants and zero, or close to zero, in plants that were well-watered, including plants that had been droughted and were subsequently rewatered, i.e. the inducible component was proven to be reversible. Gas-exchange measurements complemented the determinations of acidity. In all species, net CO2 uptake was restricted to the light in well-watered plants, and cessation of watering was followed by a progressive reduction of CO2 uptake in the light and a reduction in nocturnal CO2 efflux. In C. creethiae, C. pentavalvis and C. reticulata net CO2 assimilation was eventually observed in the dark, whereas in C. quadrivalvis nocturnal CO2 exchange approached the compensation point but did not transition to net CO2 gain. Following rewatering, all species returned to their original well-watered CO2 exchange pattern of net CO2 uptake restricted solely to the light. In addition to facultative CAM, C. quadrivalvis and C. reticulata exhibited an extremely small constitutive CAM component as demonstrated by the nocturnal accumulation in well-watered plants of small amounts of acidity and by the curved pattern of the nocturnal course of CO2 efflux. It is suggested that low-level CAM and facultative CAM are more common within the Australian succulent flora, and perhaps the world succulent flora, than has been previously assumed.
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Affiliation(s)
- Joseph A M Holtum
- College of Science and Engineering, James Cook University, Townsville, QLD, 4811, Australia.
- Smithsonian Tropical Research Institute, PO Box 0843-03092, Balboa, Ancón, Republic of Panama.
| | - Lillian P Hancock
- Department of Ecology and Evolutionary Biology, Brown University, Box G-W, Providence, RI, 02912, USA
| | - Erika J Edwards
- Department of Ecology and Evolutionary Biology, Brown University, Box G-W, Providence, RI, 02912, USA
| | - Klaus Winter
- Smithsonian Tropical Research Institute, PO Box 0843-03092, Balboa, Ancón, Republic of Panama
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Negin B, Moshelion M. The evolution of the role of ABA in the regulation of water-use efficiency: From biochemical mechanisms to stomatal conductance. Plant Sci 2016; 251:82-89. [PMID: 27593466 DOI: 10.1016/j.plantsci.2016.05.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 05/09/2016] [Accepted: 05/12/2016] [Indexed: 05/21/2023]
Abstract
Abscisic acid is found in a wide variety of organisms. In the plant kingdom, ABA's role in mediating responses to abiotic stress has been conserved and enhanced throughout evolution. The emergence of plants to terrestrial environments required the development of mechanisms to cope with ongoing and severe abiotic stress such as drought and rapid changes in humidity and temperature. The common understanding is that terrestrial plants evolved strategies ranging from desiccation-tolerance mechanisms (mosses) to drought tolerance (CAM plants), to better exploit different ecological niches. In between these divergent water regulation strategies, ABA plays a significant role in managing plants' adaptation to new environments by optimizing water-use efficiency (WUE) under particular environmental conditions. ABA plays some very different roles in the regulation of WUE. ABA's role in the regulation of guard cells and transpiration has yielded a wide variety of WUE-regulation mechanisms, ranging from no sensitivity (ferns) to low sensitivity (anisohydric behavior) to hypersensitivity to ABA (isohydric behavior and putatively CAM plants). ABA also plays a role in the regulation of non-stomatal, biochemical mechanisms of WUE regulation. In angiosperms, this includes the control of osmotic adjustment and morphological changes, including changes in leaf size, stomatal density, stomatal size and root development. Under severe stress, ABA also appears to initiate leaf senescence via transcriptional regulation, to directly inhibit photosynthesis.
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Affiliation(s)
- Boaz Negin
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel.
| | - Menachem Moshelion
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel.
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Barkla BJ, Vera-Estrella R, Raymond C. Single-cell-type quantitative proteomic and ionomic analysis of epidermal bladder cells from the halophyte model plant Mesembryanthemum crystallinum to identify salt-responsive proteins. BMC Plant Biol 2016; 16:110. [PMID: 27160145 PMCID: PMC4862212 DOI: 10.1186/s12870-016-0797-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 05/02/2016] [Indexed: 05/03/2023]
Abstract
BACKGROUND Epidermal bladder cells (EBC) are large single-celled, specialized, and modified trichomes found on the aerial parts of the halophyte Mesembryanthemum crystallinum. Recent development of a simple but high throughput technique to extract the contents from these cells has provided an opportunity to conduct detailed single-cell-type analyses of their molecular characteristics at high resolution to gain insight into the role of these cells in the salt tolerance of the plant. RESULTS In this study, we carry out large-scale complementary quantitative proteomic studies using both a label (DIGE) and label-free (GeLC-MS) approach to identify salt-responsive proteins in the EBC extract. Additionally we perform an ionomics analysis (ICP-MS) to follow changes in the amounts of 27 different elements. Using these methods, we were able to identify 54 proteins and nine elements that showed statistically significant changes in the EBC from salt-treated plants. GO enrichment analysis identified a large number of transport proteins but also proteins involved in photosynthesis, primary metabolism and Crassulacean acid metabolism (CAM). Validation of results by western blot, confocal microscopy and enzyme analysis helped to strengthen findings and further our understanding into the role of these specialized cells. As expected EBC accumulated large quantities of sodium, however, the most abundant element was chloride suggesting the sequestration of this ion into the EBC vacuole is just as important for salt tolerance. CONCLUSIONS This single-cell type omics approach shows that epidermal bladder cells of M. crystallinum are metabolically active modified trichomes, with primary metabolism supporting cell growth, ion accumulation, compatible solute synthesis and CAM. Data are available via ProteomeXchange with identifier PXD004045.
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Affiliation(s)
- Bronwyn J Barkla
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW 2480, Australia.
| | - Rosario Vera-Estrella
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, MOR, México
| | - Carolyn Raymond
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW 2480, Australia
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Oh DH, Barkla BJ, Vera-Estrella R, Pantoja O, Lee SY, Bohnert HJ, Dassanayake M. Cell type-specific responses to salinity - the epidermal bladder cell transcriptome of Mesembryanthemum crystallinum. New Phytol 2015; 207:627-44. [PMID: 25944243 DOI: 10.1111/nph.13414] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 03/08/2015] [Indexed: 05/18/2023]
Abstract
Mesembryanthemum crystallinum (ice plant) exhibits extreme tolerance to salt. Epidermal bladder cells (EBCs), developing on the surface of aerial tissues and specialized in sodium sequestration and other protective functions, are critical for the plant's stress adaptation. We present the first transcriptome analysis of EBCs isolated from intact plants, to investigate cell type-specific responses during plant salt adaptation. We developed a de novo assembled, nonredundant EBC reference transcriptome. Using RNAseq, we compared the expression patterns of the EBC-specific transcriptome between control and salt-treated plants. The EBC reference transcriptome consists of 37 341 transcript-contigs, of which 7% showed significantly different expression between salt-treated and control samples. We identified significant changes in ion transport, metabolism related to energy generation and osmolyte accumulation, stress signalling, and organelle functions, as well as a number of lineage-specific genes of unknown function, in response to salt treatment. The salinity-induced EBC transcriptome includes active transcript clusters, refuting the view of EBCs as passive storage compartments in the whole-plant stress response. EBC transcriptomes, differing from those of whole plants or leaf tissue, exemplify the importance of cell type-specific resolution in understanding stress adaptive mechanisms.
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Affiliation(s)
- Dong-Ha Oh
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Bronwyn J Barkla
- Southern Cross Plant Science, Southern Cross University, PO Box 157, Lismore, NSW, 2480, Australia
| | - Rosario Vera-Estrella
- Instituto de Biotecnología, UNAM, A.P. 510-3, Colonia Miraval, Cuernavaca, MOR, 62250, México
| | - Omar Pantoja
- Instituto de Biotecnología, UNAM, A.P. 510-3, Colonia Miraval, Cuernavaca, MOR, 62250, México
| | - Sang-Yeol Lee
- Division of Applied Life Science, Gyeongsang National University, Jinju, 660-701, South Korea
| | - Hans J Bohnert
- Departments of Plant Biology and of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Maheshi Dassanayake
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA
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Einzmann HJR, Beyschlag J, Hofhansl F, Wanek W, Zotz G. Host tree phenology affects vascular epiphytes at the physiological, demographic and community level. AoB Plants 2014; 7:plu073. [PMID: 25392188 PMCID: PMC4287691 DOI: 10.1093/aobpla/plu073] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 10/27/2014] [Indexed: 05/27/2023]
Abstract
The processes that govern diverse tropical plant communities have rarely been studied in life forms other than trees. Structurally dependent vascular epiphytes, a major part of tropical biodiversity, grow in a three-dimensional matrix defined by their hosts, but trees differ in their architecture, bark structure/chemistry and leaf phenology. We hypothesized that the resulting seasonal differences in microclimatic conditions in evergreen vs. deciduous trees would affect epiphytes at different levels, from organ physiology to community structure. We studied the influence of tree leaf phenology on vascular epiphytes on the Island of Barro Colorado, Panama. Five tree species were selected, which were deciduous, semi-deciduous or evergreen. The crowns of drought-deciduous trees, characterized by sunnier and drier microclimates, hosted fewer individuals and less diverse epiphyte assemblages. Differences were also observed at a functional level, e.g. epiphyte assemblages in deciduous trees had larger proportions of Crassulacean acid metabolism species and individuals. At the population level a drier microclimate was associated with lower individual growth and survival in a xerophytic fern. Some species also showed, as expected, lower specific leaf area and higher δ(13)C values when growing in deciduous trees compared with evergreen trees. As hypothesized, host tree leaf phenology influences vascular epiphytes at different levels. Our results suggest a cascading effect of tree composition and associated differences in tree phenology on the diversity and functioning of epiphyte communities in tropical lowland forests.
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Affiliation(s)
- Helena J R Einzmann
- Department of Biology and Environmental Sciences, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Straße 9-11, D-26111 Oldenburg, Germany
| | - Joachim Beyschlag
- Department of Biology and Environmental Sciences, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Straße 9-11, D-26111 Oldenburg, Germany
| | - Florian Hofhansl
- Department of Microbiology and Ecosystem Science, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
| | - Wolfgang Wanek
- Department of Microbiology and Ecosystem Science, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
| | - Gerhard Zotz
- Department of Biology and Environmental Sciences, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Straße 9-11, D-26111 Oldenburg, Germany Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Balboa, Ancon, Panamá, República de Panamá
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Abstract
• The Bromeliaceae encompass predominantly rosette, terrestrial or epiphytic species, including C3 and crassulacean acid metabolism (CAM) photosynthetic types within its three subfamilies. Here, leaf diurnal changes and longitudinal gradients of soluble sugars, organic acids and starch, were quantified to estimate the rates of carbohydrate translocation from mature leaves of C3 and CAM species. • Leaves of Ananas comosus, Aechmea fendleri, Bromelia humilis, Guzmania mucronata, Tillandsia fendleri, Tillandsia flexuosa and Tillandsia utriculata, were sampled at the base, middle, and upper sections during the day. We measured osmolality in sap from frozen subsamples, sugars and organic acids in hot-water extracts from microwave-dried subsamples, and starch hydrolysed with α-amylase or 1.1% HCl. • CAM activity was expressed by malate accumulation, citrate was present, but fluctuations were not significant. Nocturnal reductions in sucrose in bromelioid CAM species accounted for most of the acidification requirements. Tillandsioid CAM species used starch for acid synthesis. Both CAM and C3 bromeliads exported significant amounts of hexose during the night, particularly from the leaf base. • Leaf bases of CAM species showed lowest acid accumulation but similar or more positive δ13 C-values to the active CAM sections. Exported carbohydrates probably derive from carbon fixed during the night period.
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Affiliation(s)
- Marianne Popp
- Universität Wien, Institut für Ökologie und Naturschutz, Vienna, Austria
| | - Heinz-Peter Janett
- Westfälische Wilhelms-Universität Münster, Institut für Angewandte Botanik, Münster, Germany
| | - Ulrich Lüttge
- Botanisches Institut der Technischen Hochschule, Darmstadt, Germany
| | - Ernesto Medina
- Centro de Ecología, Instituto Venezolano de Investigaciones Científicas, Caracas, Venezuela
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Adams WW, Díaz M, Winter K. Diurnal changes in photochemical efficiency, the reduction state of Q, radiationless energy dissipation, and non-photochemical fluorescence quenching in cacti exposed to natural sunlight in northern Venezuela. Oecologia 1989; 80:553-561. [PMID: 28312843 DOI: 10.1007/bf00380081] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/1988] [Indexed: 10/26/2022]
Abstract
Diurnal measurements of chlorophyll a fluorescence from cacti (Nopalea cochenillifera, Opuntia ficus-indica, and Opuntia wentiana) growing in northern Venezuela were used to determine photochemical fluorescence quenching related to the reduction state of the primary electron acceptor of PS II as well as non-photochemical fluorescence quenching which reflects the fraction of energy going primarily into radiationless deexcitation. The cladodes used in this study were oriented such that one surface received direct sunlight in the morning and the other one during the afternoon. Both surfaces exhibited large increases in radiationless energy dissipation from the photochemical system accompanied by decreases in PS II photochemical efficiency during direct exposure to natural sunlight. During exposure to sunlight in the morning, dissipation of absorbed light energy through photosynthesis and radiationless energy dissipation was sufficient to maintain Q, the primary electron acceptor for PS II, in a low reduction state. During exposure to sunlight in the afternoon, however, the reduction state of Q rose to levels greater than 50%, presumably due to a decrease in photosynthetic electron transport as the decarboxylation of the nocturnally accumulated malic acid was completed. Exposure to direct sunlight in the afternoon also led to more sustained increases in radiationless energy dissipation. Furthermore, the increases in radiationless energy dissipation during exposure of a water-stressed cladode of O. wentiana to direct sunlight were much greater than those from other well-watered cacti, presumably due to sustained stomatal closure and decreased rates of photosynthetic electron transport. These results indicate that the radiationless dissipation of absorbed light is an important process in these CAM plants under natural conditions, and may reflect a protective mechanism against the potentially damaging effects of the accumulation of excessive energy, particularly under conditions where CO2 availability is restricted.
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Affiliation(s)
- W W Adams
- Lehrstuhl für Botanik II, Universität Würzburg, Mittlerer Dallenbergweg 64, D-8700, Würzburg, Federal Republic of Germany
| | - M Díaz
- Centro de Investigaciones en Ecologia y Zonas Aridas, Universidad Francisco de Miranda, P.O. Box 7506, Coro, Falcón, Venezuela
| | - K Winter
- Lehrstuhl für Botanik II, Universität Würzburg, Mittlerer Dallenbergweg 64, D-8700, Würzburg, Federal Republic of Germany
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Adams WW 3rd, Smith SD, Osmond CB. Photoinhibition of the CAM succulent Opuntia basilaris growing in Death Valley: evidence from 77K fluorescence and quantum yield. Oecologia 1987; 71:221-8. [PMID: 28312248 DOI: 10.1007/BF00377287] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/1986] [Indexed: 10/26/2022]
Abstract
Diurnal measurements of low temperature (77K) fluorescence at 690 nm (PS II) from north, south, east, and west facing cladode surfaces of Opuntia basilaris in Death Valley, California were made on six occasions during 1985. The absolute levels of F o(instantaneous fluorescence) and F m(maximum fluorescence), as well as the ratio F v/F m(variable fluorescence, F m-F o, over maximum fluorescence), were greater in the north face relative to the other faces. Diurnal decreases in F o, F mand F v/F mwere found concomitant with increases in incident photon flux area density (PFD). F v/F mwas fairly low throughout the year, indicative of photoinhibition, but became somewhat elevated after a spring rain. In early fall the quantum yield of the south face was considerably depressed relative to that of the north face, and corresponding differences were observed in F v/F m. A decrease in PFD during growth of glasshouse plants led to an increase in chlorophyll concentration, F oand F m, but not F v/F m. Although there was some variability in the quantum yield of well watered glasshouse cladodes, a correlation was found between quantum yield and the light and CO2 saturated rate of photosynthesis. When O. basilaris was water stressed under glasshouse conditions, reductions in quantum yield, F m, and F v/F mwere observed. Reductions in F v/F malways indicated a reduced quantum yield, although the converse was not necessarily so in well watered glasshouse plants. The results of this study indicate that O. basilaris is likely to experience photoinhibition throughout much of its life in Death Valley.
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