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Cerrato MD, Mir-Rosselló PM, Cortés-Fernández I, Ribas-Serra A, Cardona C, Sureda A, Flexas J, Gil L. Salinity stress on three representative species from Mediterranean semifixed dunes: Assessment of salinity exposure and substrate conductivity data reveal variable response strategies and tolerance between species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 950:175178. [PMID: 39122049 DOI: 10.1016/j.scitotenv.2024.175178] [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: 03/17/2024] [Revised: 07/29/2024] [Accepted: 07/29/2024] [Indexed: 08/12/2024]
Abstract
Coastal ecotones can disrupt natural conditions, yielding intricate ecological contexts where salinity plays a variable role. The aim of this study was to assess the salinity effect on three species representatives of semifixed dune (Crucianella maritima, Helianthemum caput-felis and Teucrium dunense). Field data were collected to assess plant cover in semifixed dunes, ecotone with other coastal habitats, and artificial Posidonia oceanica wracks. Soil samples were collected, and conductivity measured. Then, experimental exposure to salinity was conducted with 6 seawater (SW) treatments (Control, 6.25 % SW, 12.5 % SW, 25 % SW, 50 % SW, 100 % SW). Flowering, gas exchange, chlorophyll fluorescence and enzymatic antioxidant measurements were conducted after two months of exposure. In the field trial, species presence varied depending on the habitat and was null on P. oceanica. The relation between conductivity and species abundance showed moderate tolerance for the three species. For C. maritima this relation was variable depending on the habitat. Experimental data suggest moderate tolerance with stress occurring at 25 % SW onwards. Gas exchange response to salinity was similar among species, but more drastic reduction in assimilation rate and larger decrease in water use efficiency was observed for C. maritima. Instead, photoinhibition occurred in H. caput-felis and T. dunense but was absent in C. maritima likely related to the fact that H. caput-felis and T. dunense activated catalase and superoxide dismutase enzymes, while C. maritima showed activation of glutathione-related enzymes. Malondialdehyde (MDA) increased in C. maritma and decreased for the other species indicating a more complex involvement of MDA under stress conditions. Flowering response to salinity was overall more resilient in T. dunense. Our results, based on field conductivity data and measurements of physiological, antioxidant, and reproductive traits, delineate specific tolerance differences and strategies towards salinity for Mediterranean semifixed dune species.
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Affiliation(s)
- M D Cerrato
- Interdisciplinary Ecology Group, Department of Biology, University of the Balearic Islands, E-07122 Palma, Balearic Islands, Spain; Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB) -Agro-Environmental and Water Economics Institute (INAGEA), E-07122 Palma, Balearic Islands, Spain.
| | - P M Mir-Rosselló
- Interdisciplinary Ecology Group, Department of Biology, University of the Balearic Islands, E-07122 Palma, Balearic Islands, Spain; Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB) -Agro-Environmental and Water Economics Institute (INAGEA), E-07122 Palma, Balearic Islands, Spain
| | - I Cortés-Fernández
- Interdisciplinary Ecology Group, Department of Biology, University of the Balearic Islands, E-07122 Palma, Balearic Islands, Spain
| | - A Ribas-Serra
- Interdisciplinary Ecology Group, Department of Biology, University of the Balearic Islands, E-07122 Palma, Balearic Islands, Spain
| | - C Cardona
- Interdisciplinary Ecology Group, Department of Biology, University of the Balearic Islands, E-07122 Palma, Balearic Islands, Spain; Centre Forestal de les Illes Balears (CEFOR‑Menut), Institut Balear de la Natura (IBANAT), C/Gremi de Corredors 10 (Polígon Son Rossinyol), 07009 Palma, Spain
| | - A Sureda
- Research Group in Community Nutrition and Oxidative Stress, University of the Balearic Islands- IUNICS, and Health Research Institute of Balearic Islands (IdISBa), E-07122 Palma, Balearic Islands, Spain; CIBEROBN (Physiopathology of Obesity and Nutrition), Instituto de Salud Carlos III, E-28029 Madrid, Spain; Research Group on Nutrition and Oxidative Stress, CIBEROBN, Guillem Colom Bldg, Universitat de les Illes Balears, Crtra. Valldemossa, km 7,5, E-07122 Palma de Mallorca, Balears, Spain
| | - J Flexas
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB) -Agro-Environmental and Water Economics Institute (INAGEA), E-07122 Palma, Balearic Islands, Spain
| | - L Gil
- Interdisciplinary Ecology Group, Department of Biology, University of the Balearic Islands, E-07122 Palma, Balearic Islands, Spain
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Pizzio GA, Mayordomo C, Illescas-Miranda J, Coego A, Bono M, Sanchez-Olvera M, Martin-Vasquez C, Samantara K, Merilo E, Forment J, Estevez JC, Nebauer SG, Rodriguez PL. Basal ABA signaling balances transpiration and photosynthesis. PHYSIOLOGIA PLANTARUM 2024; 176:e14494. [PMID: 39210540 DOI: 10.1111/ppl.14494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 07/31/2024] [Indexed: 09/04/2024]
Abstract
The balance between the CO2 entry for photosynthesis and transpiration water loss is crucial for plant growth, and ABA signaling can affect this equilibrium. To test how ABA balances plant growth and environmental adaptation, we performed molecular genetics studies in the biotech crop Nicotiana benthamiana under well-watered or drought conditions. Studies on ABA signaling in crops are complicated by the multigenic nature of the PYR/PYL/RCAR ABA receptor family and its functional redundancy, which is particularly challenging in polyploid plants. We have generated a pentuple pyl mutant in the allotetraploid Nicotiana benthamiana through CRISPR/Cas9 gene editing. The pentuple mutant is impaired in 2 NbPYL1-like and 3 NbPYL8-like receptors, affecting the regulation of transpiration and several ABA-dependent transcriptional processes. RNA-seq and metabolite analysis revealed that the synthesis of galactinol, an essential precursor for the osmoprotective raffinose family of oligosaccharides, is ABA-dependent and impaired in the mutant under osmotic stress. In contrast, our results show that, under well-watered conditions, partial inactivation of ABA signaling leads to higher CO2 entry and photosynthesis in the mutant than in WT. Photosynthesis analyses revealed an increased CO2 diffusion capacity mediated by higher stomatal and mesophyll conductances, and higher substomatal CO2 concentration in the pentuple mutant. RNA-seq analyses revealed that genes associated with cell wall loosening (e.g., expansins) and porosity were strongly downregulated by ABA in WT. In summary, a partial relief of the ABA control on transpiration mediated by ABA receptors positively affects photosynthesis when water is not limited, at the expense of reduced water use efficiency.
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Affiliation(s)
- Gaston A Pizzio
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Cristian Mayordomo
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Jonatan Illescas-Miranda
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Alberto Coego
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Mar Bono
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Mayra Sanchez-Olvera
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Constanza Martin-Vasquez
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Kajal Samantara
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Ebe Merilo
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Javier Forment
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Juan Carlos Estevez
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Sergio G Nebauer
- Plant Production Department, Universitat Politècnica de València, Valencia, Spain
| | - Pedro L Rodriguez
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
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Hu W, Loka DA, Yang Y, Wu Z, Wang J, Liu L, Wang S, Zhou Z. Partial root-zone drying irrigation improves intrinsic water-use efficiency and maintains high photosynthesis by uncoupling stomatal and mesophyll conductance in cotton leaves. PLANT, CELL & ENVIRONMENT 2024; 47:3147-3165. [PMID: 38693776 DOI: 10.1111/pce.14932] [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: 07/17/2023] [Revised: 04/14/2024] [Accepted: 04/17/2024] [Indexed: 05/03/2024]
Abstract
Partial root-zone drying irrigation (PRD) can improve water-use efficiency (WUE) without reductions in photosynthesis; however, the mechanism by which this is attained is unclear. To amend that, PRD conditions were simulated by polyethylene glycol 6000 in a root-splitting system and the effects of PRD on cotton growth were studied. Results showed that PRD decreased stomatal conductance (gs) but increased mesophyll conductance (gm). Due to the contrasting effects on gs and gm, net photosynthetic rate (AN) remained unaffected, while the enhanced gm/gs ratio facilitated a larger intrinsic WUE. Further analyses indicated that PRD-induced reduction of gs was related to decreased stomatal size and stomatal pore area in adaxial and abaxial surface which was ascribed to lower pore length and width. PRD-induced variation of gm was ascribed to the reduced liquid-phase resistance, due to increases in chloroplast area facing to intercellular airspaces and the ratio of chloroplast surface area to total mesophyll cell area exposed to intercellular airspaces, as well as to decreases in the distance between cell wall and chloroplast, and between adjacent chloroplasts. The above results demonstrate that PRD, through alterations to stomatal and mesophyll structures, decoupled gs and gm responses, which ultimately increased intrinsic WUE and maintained AN.
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Affiliation(s)
- Wei Hu
- College of Agriculture, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Dimitra A Loka
- Institute of Industrial and Forage Crops, Hellenic Agricultural Organization, Larisa, Greece
| | - Yuanli Yang
- College of Agriculture, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Ziqing Wu
- College of Agriculture, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Jun Wang
- College of Agriculture, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Lin Liu
- College of Agriculture, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Shanshan Wang
- College of Agriculture, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Zhiguo Zhou
- College of Agriculture, Nanjing Agricultural University, Nanjing, People's Republic of China
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Arzac MI, Miranda-Apodaca J, de Los Ríos A, Castanyer-Mallol F, García-Plazaola JI, Fernández-Marín B. The outstanding capacity of Prasiola antarctica to thrive in contrasting harsh environments relies on the constitutive protection of thylakoids and on morphological plasticity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 119:65-83. [PMID: 38608130 DOI: 10.1111/tpj.16742] [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: 03/26/2023] [Revised: 02/29/2024] [Accepted: 03/14/2024] [Indexed: 04/14/2024]
Abstract
The determination of physiological tolerance ranges of photosynthetic species and of the biochemical mechanisms underneath are fundamental to identify target processes and metabolites that will inspire enhanced plant management and production for the future. In this context, the terrestrial green algae within the genus Prasiola represent ideal models due to their success in harsh environments (polar tundras) and their extraordinary ecological plasticity. Here we focus on the outstanding Prasiola antarctica and compare two natural populations living in very contrasting microenvironments in Antarctica: the dry sandy substrate of a beach and the rocky bed of an ephemeral freshwater stream. Specifically, we assessed their photosynthetic performance at different temperatures, reporting for the first time gnsd values in algae and changes in thylakoid metabolites in response to extreme desiccation. Stream population showed lower α-tocopherol content and thicker cell walls and thus, lower gnsd and photosynthesis. Both populations had high temperatures for optimal photosynthesis (around +20°C) and strong constitutive tolerance to freezing and desiccation. This tolerance seems to be related to the high constitutive levels of xanthophylls and of the cylindrical lipids di- and tri-galactosyldiacylglycerol in thylakoids, very likely related to the effective protection and stability of membranes. Overall, P. antarctica shows a complex battery of constitutive and plastic protective mechanisms that enable it to thrive under harsh conditions and to acclimate to very contrasting microenvironments, respectively. Some of these anatomical and biochemical adaptations may partially limit photosynthesis, but this has a great potential to rise in a context of increasing temperature.
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Affiliation(s)
- Miren I Arzac
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940, Leioa, Spain
| | - Jon Miranda-Apodaca
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940, Leioa, Spain
| | - Asunción de Los Ríos
- Museo Nacional de Ciencias Naturales (MNCN-CSIC), Serrano 115 dpdo, 28006, Madrid, Spain
| | - Francesc Castanyer-Mallol
- Research Group on Plant Biology under Mediterranean Conditions, Department of Biology, Universitat de les Illes Balears (UIB), INAGEA, Balearic Islands, Palma, Spain
| | - José I García-Plazaola
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940, Leioa, Spain
| | - Beatriz Fernández-Marín
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940, Leioa, Spain
- Department of Botany, Ecology and Plant Physiology, University of La Laguna (ULL), Canary Islands, 38200, La Laguna, Spain
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Patel J, Khatri K, Khandwal D, Gupta NK, Choudhary B, Hapani D, Koshiya J, Syed SN, Phillips DW, Jones HD, Mishra A. Modulation of physio-biochemical and photosynthesis parameters by overexpressing SbPIP2 gene improved abiotic stress tolerance of transgenic tobacco. PHYSIOLOGIA PLANTARUM 2024; 176:e14384. [PMID: 38859697 DOI: 10.1111/ppl.14384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 05/13/2024] [Accepted: 05/21/2024] [Indexed: 06/12/2024]
Abstract
The present study aims to explore the potential of a plasma-membrane localized PIP2-type aquaporin protein sourced from the halophyte Salicornia brachiata to alleviate salinity and water deficit stress tolerance in a model plant through transgenic intervention. Transgenic plants overexpressing SbPIP2 gene showed improved physio-biochemical parameters like increased osmolytes (proline, total sugar, and amino acids), antioxidants (polyphenols), pigments and membrane stability under salinity and drought stresses compared to control plants [wild type (WT) and vector control (VC) plants]. Multivariate statistical analysis showed that, under water and salinity stresses, osmolytes, antioxidants and pigments were correlated with SbPIP2-overexpressing (SbPIP2-OE) plants treated with salinity and water deficit stress, suggesting their involvement in stress tolerance. As aquaporins are also involved in CO2 transport, SbPIP2-OE plants showed enhanced photosynthesis performance than wild type upon salinity and drought stresses. Photosynthetic gas exchange (net CO2 assimilation rate, PSII efficiency, ETR, and non-photochemical quenching) were significantly higher in SbPIP2-OE plants compared to control plants (wild type and vector control plants) under both unstressed and stressed conditions. The higher quantum yield for reduction of end electron acceptors at the PSI acceptor side [Φ( R0 )] in SbPIP2-OE plants compared to control plants under abiotic stresses indicates a continued PSI functioning, leading to retained electron transport rate, higher carbon assimilation, and less ROS-mediated injuries. In conclusion, the SbPIP2 gene functionally validated in the present study could be a potential candidate for engineering abiotic stress resilience in important crops.
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Affiliation(s)
- Jaykumar Patel
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Kusum Khatri
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
| | - Deepesh Khandwal
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Nirmala Kumari Gupta
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Babita Choudhary
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Divya Hapani
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
| | - Jignasha Koshiya
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
| | - Saif Najam Syed
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Dylan Wyn Phillips
- Department of Life Sciences, Aberystwyth University, Aberystwyth, Ceredigion, United Kingdom
| | - Huw Dylan Jones
- Department of Life Sciences, Aberystwyth University, Aberystwyth, Ceredigion, United Kingdom
| | - Avinash Mishra
- CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
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Brunello L, Polverini E, Lauria G, Landi M, Guidi L, Loreti E, Perata P. Root photosynthesis prevents hypoxia in the epiphytic orchid Phalaenopsis. FUNCTIONAL PLANT BIOLOGY : FPB 2024; 51:FP23227. [PMID: 38442921 DOI: 10.1071/fp23227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 02/14/2024] [Indexed: 03/07/2024]
Abstract
Orchids (Phalaenopsis spp.) growing in tropical and subtropical regions are epiphytes. As such, they grow on trees with the root system utilised to anchor themselves to tree branches. These roots are highly specialised, display a large diameter and are often green, suggesting the ability to carry out photosynthesis. However, the role of photosynthesis in orchid roots is controversial. Orchids that are leafless can photosynthesise in their roots, thus indicating that some orchid roots carry out photosynthesis in a similar manner to leaves. However, the primary site of photosynthesis in orchids are in their leaves, and the roots of epiphytic orchids may mostly conduct internal refixation of respiratory CO2 . Besides contributing to the overall carbon metabolism of orchid plants, oxygen produced through root photosynthesis may also be important by alleviating potential root hypoxia. The bulky tissue of most epiphytic orchid roots suggests that oxygen diffusion in these roots can be limited. Here, we demonstrate that the bulky roots of a widely commercially cultivated orchid belonging to the genus Phalaenopsis are hypoxic in the dark. These roots are photosynthetically active and produce oxygen when exposed to light, thus mitigating root hypoxia.
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Affiliation(s)
- Luca Brunello
- PlantLab, Center of Plant Sciences, Sant'Anna School of Advanced Studies, Via Guidiccioni 10, San Giuliano Terme 56010, Italy
| | - Ester Polverini
- PlantLab, Center of Plant Sciences, Sant'Anna School of Advanced Studies, Via Guidiccioni 10, San Giuliano Terme 56010, Italy
| | - Giulia Lauria
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, Pisa 56124, Italy
| | - Marco Landi
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, Pisa 56124, Italy
| | - Lucia Guidi
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, Pisa 56124, Italy
| | - Elena Loreti
- Institute of Agricultural Biology and Biotechnology, National Research Council, Via Moruzzi 1, Pisa 56124, Italy
| | - Pierdomenico Perata
- PlantLab, Center of Plant Sciences, Sant'Anna School of Advanced Studies, Via Guidiccioni 10, San Giuliano Terme 56010, Italy
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Solhaug KA, Eiterjord G, Løken MH, Gauslaa Y. Non-photochemical quenching may contribute to the dominance of the pale mat-forming lichen Cladonia stellaris over the sympatric melanic Cetraria islandica. Oecologia 2024; 204:187-198. [PMID: 38233688 PMCID: PMC10830725 DOI: 10.1007/s00442-023-05498-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 12/10/2023] [Indexed: 01/19/2024]
Abstract
The mat-forming fruticose lichens Cladonia stellaris and Cetraria islandica frequently co-occur on soils in sun-exposed boreal, subarctic, and alpine ecosystems. While the dominant reindeer lichen Cladonia lacks a cortex but produces the light-reflecting pale pigment usnic acid on its surface, the common but patchier Cetraria has a firm cortex sealed by the light-absorbing pigment melanin. By measuring reflectance spectra, high-light tolerance, photosynthetic responses, and chlorophyll fluorescence in sympatric populations of these lichens differing in fungal pigments, we aimed to study how they cope with high light while hydrated. Specimens of the two species tolerated high light equally well but with different protective mechanisms. The mycobiont of the melanic species efficiently absorbed excess light, consistent with a lower need for its photobiont to protect itself by non-photochemical quenching (NPQ). By contrast, usnic acid screened light at 450-700 nm by reflectance and absorbed shorter wavelengths. The ecorticate usnic species with less efficient fungal light screening exhibited a consistently lower light compensation point and higher CO2 uptake rates than the melanic lichen. In both species, steady state NPQ rapidly increased at increasing light with no signs of light saturation. To compensate for less internal shading causing light fluctuations with a larger amplitude, the usnic lichen photobiont adjusted to changing light by faster induction and faster relaxation of NPQ rapidly transforming excess excitation energy to less damaging heat. The high and flexible NPQ tracking fluctuations in solar radiation probably contributes to the strong dominance of the usnic mat-forming Cladonia in open lichen-dominated heaths.
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Affiliation(s)
- Knut Asbjørn Solhaug
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
| | - Gaute Eiterjord
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
| | - Martine Hana Løken
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
| | - Yngvar Gauslaa
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway.
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Vergara-Diaz O, Velasco-Serrano E, Invernón-Garrido A, Katamadze A, Yoldi-Achalandabaso A, Serret MD, Vicente R. Quinoa panicles contribute to carbon assimilation and are more tolerant to salt stress than leaves. JOURNAL OF PLANT PHYSIOLOGY 2024; 292:154161. [PMID: 38142485 DOI: 10.1016/j.jplph.2023.154161] [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: 08/02/2023] [Revised: 11/20/2023] [Accepted: 12/08/2023] [Indexed: 12/26/2023]
Abstract
Contribution of inflorescences to seed filling have attracted great attention given the resilience of this photosynthetic organ to stressful conditions. However, studies have been almost exclusively focused to small grain cereals. In this study, we aimed to explore these responses in quinoa, as a climate resilient seed crop of elevated economic and nutritious potential. We compared the physiological and metabolic performance of panicles and leaves of two quinoa cultivars growing under contrasting salinity levels. Plant growth, photosynthetic and transpiratory gas exchange and chlorophyll fluorescence were monitored in inflorescences and leaves throughout the experiment. At flowering stage, young and mature leaves and panicles were sampled for key metabolic markers related to carbon, nitrogen and secondary metabolisms. When subjected to salt stress, panicles showed attenuated declines on photosynthesis, water use, pigments, amino acids, and protein levels as compared to leaves. In fact, the assimilation rates, together with a high hexose content evidenced an active photosynthetic role of the panicle under optimal and salt stress conditions. Moreover, we also found significant genotypic variability for physiological and metabolic traits of panicles and leaves, which emphasizes the study of genotype-dependent stress responses at the whole plant level. We conclude that quinoa panicles are less affected by salt stress than leaves, which encourages further research and exploitation of this organ for crop improvement and stress resilience considering the high natural diversity.
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Affiliation(s)
- Omar Vergara-Diaz
- Plant Ecophysiology and Metabolism Group, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), 2780-157, Oeiras, Portugal.
| | - Elena Velasco-Serrano
- Integrative Crop Ecophysiology Group, Section of Plant Physiology, Faculty of Biology, University of Barcelona, 08028, Barcelona, Spain; AGROTECNIO-CERCA Center, 25198, Lleida, Spain.
| | - Alicia Invernón-Garrido
- Integrative Crop Ecophysiology Group, Section of Plant Physiology, Faculty of Biology, University of Barcelona, 08028, Barcelona, Spain; AGROTECNIO-CERCA Center, 25198, Lleida, Spain.
| | - Artūrs Katamadze
- Plant Ecophysiology and Metabolism Group, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), 2780-157, Oeiras, Portugal.
| | - Ander Yoldi-Achalandabaso
- Plant Ecophysiology and Metabolism Group, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), 2780-157, Oeiras, Portugal; FisioClimaCO(2) Group, Department of Plant Biology and Ecology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080, Bilbao, Spain.
| | - Maria Dolores Serret
- Integrative Crop Ecophysiology Group, Section of Plant Physiology, Faculty of Biology, University of Barcelona, 08028, Barcelona, Spain; AGROTECNIO-CERCA Center, 25198, Lleida, Spain.
| | - Rubén Vicente
- Plant Ecophysiology and Metabolism Group, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), 2780-157, Oeiras, Portugal.
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