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Peláez-Vico MÁ, Zandalinas SI, Devireddy AR, Sinha R, Mittler R. Systemic stomatal responses in plants: Coordinating development, stress, and pathogen defense under a changing climate. PLANT, CELL & ENVIRONMENT 2024; 47:1171-1184. [PMID: 38164061 DOI: 10.1111/pce.14797] [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: 10/21/2023] [Revised: 11/30/2023] [Accepted: 12/15/2023] [Indexed: 01/03/2024]
Abstract
To successfully survive, develop, grow and reproduce, multicellular organisms must coordinate their molecular, physiological, developmental and metabolic responses among their different cells and tissues. This process is mediated by cell-to-cell, vascular and/or volatile communication, and involves electric, chemical and/or hydraulic signals. Within this context, stomata serve a dual role by coordinating their responses to the environment with their neighbouring cells at the epidermis, but also with other stomata present on other parts of the plant. As stomata represent one of the most important conduits between the plant and its above-ground environment, as well as directly affect photosynthesis, respiration and the hydraulic status of the plant by controlling its gas and vapour exchange with the atmosphere, coordinating the overall response of stomata within and between different leaves and tissues plays a cardinal role in plant growth, development and reproduction. Here, we discuss different examples of local and systemic stomatal coordination, the different signalling pathways that mediate them, and the importance of systemic stomatal coordination to our food supply, ecosystems and weather patterns, under our changing climate. We further discuss the potential biotechnological implications of regulating systemic stomatal responses for enhancing agricultural productivity in a warmer and CO2 -rich environment.
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Affiliation(s)
- María Ángeles Peláez-Vico
- Division of Plant Sciences and Technology, College of Agriculture Food and Natural Resources and Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri, USA
| | - Sara I Zandalinas
- Department of Biology, Biochemistry and Environmental Sciences, University Jaume I, Castelló de la Plana, Spain
| | - Amith R Devireddy
- Center for Bioenergy Innovation and Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Ranjita Sinha
- Division of Plant Sciences and Technology, College of Agriculture Food and Natural Resources and Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri, USA
| | - Ron Mittler
- Division of Plant Sciences and Technology, College of Agriculture Food and Natural Resources and Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri, USA
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Wang L, Chang C. Stomatal improvement for crop stress resistance. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1823-1833. [PMID: 38006251 DOI: 10.1093/jxb/erad477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 11/23/2023] [Indexed: 11/26/2023]
Abstract
The growth and yield of crop plants are threatened by environmental challenges such as water deficit, soil flooding, high salinity, and extreme temperatures, which are becoming increasingly severe under climate change. Stomata contribute greatly to plant adaptation to stressful environments by governing transpirational water loss and photosynthetic gas exchange. Increasing evidence has revealed that stomata formation is shaped by transcription factors, signaling peptides, and protein kinases, which could be exploited to improve crop stress resistance. The past decades have seen unprecedented progress in our understanding of stomata formation, but most of these advances have come from research on model plants. This review highlights recent research in stomata formation in crops and its multifaceted functions in abiotic stress tolerance. Current strategies, limitations, and future directions for harnessing stomatal development to improve crop stress resistance are discussed.
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Affiliation(s)
- Lu Wang
- College of Life Sciences, Qingdao University, Qingdao, Shandong, China
| | - Cheng Chang
- College of Life Sciences, Qingdao University, Qingdao, Shandong, China
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Jacomassi LM, Pacola M, Momesso L, Viveiros J, Júnior OA, de Siqueira GF, de Campos M, Crusciol CAC. Foliar Application of Amino Acids and Nutrients as a Tool to Mitigate Water Stress and Stabilize Sugarcane Yield and Bioenergy Generation. PLANTS (BASEL, SWITZERLAND) 2024; 13:461. [PMID: 38337992 PMCID: PMC10857448 DOI: 10.3390/plants13030461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 01/09/2024] [Accepted: 01/27/2024] [Indexed: 02/12/2024]
Abstract
Extended periods of water stress negatively affect sugarcane crop production. The foliar application of supplements containing specific nutrients and/or organic molecules such as amino acids can improve sugarcane metabolism, stalk and sugar yields, and the quality of the extracted juice. The present study assessed the effectiveness of the foliar application of an abiotic stress protection complement (ASPC) composed of 18 amino acids and 5 macronutrients. The experiments were carried out in the field with two treatments and twelve replicates. The two treatments were no application of ASPC (control) and foliar application of ASPC. The foliar application of ASPC increased the activity of antioxidant enzymes. The Trolox-equivalent antioxidant capacity (DPPH) was higher in ASPC-treated plants than in control plants, reflecting higher antioxidant enzyme activity and lower malondialdehyde (MDA) levels. The level of H2O2 was 11.27 nM g-1 protein in plants treated with ASPC but 23.71 nM g-1 protein in control plants. Moreover, the application of ASPC increased stalk yield and sucrose accumulation, thus increasing the quality of the raw material. By positively stabilizing the cellular redox balance in sugarcane plants, ASPC application also increased energy generation. Therefore, applying ASPC is an effective strategy for relieving water stress while improving crop productivity.
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Affiliation(s)
- Lucas Moraes Jacomassi
- Department of Crop Science, College of Agricultural Science, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (L.M.J.); (M.P.); (J.V.); (O.A.J.); (G.F.d.S.); (M.d.C.)
| | - Marcela Pacola
- Department of Crop Science, College of Agricultural Science, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (L.M.J.); (M.P.); (J.V.); (O.A.J.); (G.F.d.S.); (M.d.C.)
| | - Letusa Momesso
- Department of Agriculutre, School of Agriculture, Federal University of Goiás (UFG), Goiânia 74690-900, GO, Brazil;
| | - Josiane Viveiros
- Department of Crop Science, College of Agricultural Science, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (L.M.J.); (M.P.); (J.V.); (O.A.J.); (G.F.d.S.); (M.d.C.)
| | - Osvaldo Araújo Júnior
- Department of Crop Science, College of Agricultural Science, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (L.M.J.); (M.P.); (J.V.); (O.A.J.); (G.F.d.S.); (M.d.C.)
| | - Gabriela Ferraz de Siqueira
- Department of Crop Science, College of Agricultural Science, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (L.M.J.); (M.P.); (J.V.); (O.A.J.); (G.F.d.S.); (M.d.C.)
| | - Murilo de Campos
- Department of Crop Science, College of Agricultural Science, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (L.M.J.); (M.P.); (J.V.); (O.A.J.); (G.F.d.S.); (M.d.C.)
| | - Carlos Alexandre Costa Crusciol
- Department of Crop Science, College of Agricultural Science, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (L.M.J.); (M.P.); (J.V.); (O.A.J.); (G.F.d.S.); (M.d.C.)
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Zhong Z, Wu Y, Zhang P, Hu G, Fu D, Yu G, Tong H. Transcriptomic Analysis Reveals Panicle Heterosis in an Elite Hybrid Rice ZZY10 and Its Parental Lines. PLANTS (BASEL, SWITZERLAND) 2023; 12:1309. [PMID: 36987003 PMCID: PMC10059593 DOI: 10.3390/plants12061309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 03/10/2023] [Accepted: 03/12/2023] [Indexed: 06/19/2023]
Abstract
Heterosis is the phenomenon in which some hybrid traits are superior to those of their parents. Most studies have analyzed the heterosis of agronomic traits of crops; however, heterosis of the panicles can improve yield and is important for crop breeding. Therefore, a systematic study of panicle heterosis is needed, especially during the reproductive stage. RNA sequencing (RNA Seq) and transcriptome analysis are suitable for further study of heterosis. Using the Illumina Nova Seq platform, the transcriptome of ZhongZheYou 10 (ZZY10), an elite rice hybrid, the maintainer line ZhongZhe B (ZZB), and the restorer line Z7-10 were analyzed at the heading date in Hangzhou, 2022. 581 million high-quality short reads were obtained by sequencing and were aligned against the Nipponbare reference genome. A total of 9000 differential expression genes were found between the hybrids and their parents (DGHP). Of the DGHP, 60.71% were up-regulated and 39.29% were down-regulated in the hybrid. Comparative transcriptome analysis revealed that 5235 and 3765 DGHP were between ZZY10 and ZhongZhe B and between ZZY10 and Z7-10, respectively. This result is consistent with the transcriptome profile of ZZY10 and was similar to Z7-10. The expression patterns of DGHP mainly exhibited over-dominance, under-dominance, and additivity. Among the DGHP-involved GO terms, pathways such as photosynthesis, DNA integration, cell wall modification, thylakoid, and photosystem were significant. 21 DGHP, which were involved in photosynthesis, and 17 random DGHP were selected for qRT-PCR validation. The up-regulated PsbQ and down-regulated subunits of PSI and PSII and photosynthetic electron transport in the photosynthesis pathway were observed in our study. Extensive transcriptome data were obtained by RNA-Seq, providing a comprehensive overview of panicle transcriptomes at the heading stage in a heterotic hybrid.
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Affiliation(s)
- Zhengzheng Zhong
- State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou 311400, China
| | - Yawen Wu
- State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou 311400, China
| | - Peng Zhang
- State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou 311400, China
| | - Guocheng Hu
- State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou 311400, China
| | - Dong Fu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Guoping Yu
- National Nanfan Research Institute, Chinese Academy of Agricultural Sciences, Sanya 572025, China
| | - Hanhua Tong
- State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou 311400, China
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Transcriptome Analysis and Intraspecific Variation in Spanish Fir ( Abies pinsapo Boiss.). Int J Mol Sci 2022; 23:ijms23169351. [PMID: 36012612 PMCID: PMC9409315 DOI: 10.3390/ijms23169351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/10/2022] [Accepted: 08/17/2022] [Indexed: 11/16/2022] Open
Abstract
Spanish fir (Abies pinsapo Boiss.) is an endemic, endangered tree that has been scarcely investigated at the molecular level. In this work, the transcriptome of Spanish fir was assembled, providing a large catalog of expressed genes (22,769), within which a high proportion were full-length transcripts (12,545). This resource is valuable for functional genomics studies and genome annotation in this relict conifer species. Two intraspecific variations of A. pinsapo can be found within its largest population at the Sierra de las Nieves National Park: one with standard green needles and another with bluish-green needles. To elucidate the causes of both phenotypes, we studied different physiological and molecular markers and transcriptome profiles in the needles. "Green" trees showed higher electron transport efficiency and enhanced levels of chlorophyll, protein, and total nitrogen in the needles. In contrast, needles from "bluish" trees exhibited higher contents of carotenoids and cellulose. These results agreed with the differential transcriptomic profiles, suggesting an imbalance in the nitrogen status of "bluish" trees. Additionally, gene expression analyses suggested that these differences could be associated with different epigenomic profiles. Taken together, the reported data provide new transcriptome resources and a better understanding of the natural variation in this tree species, which can help improve guidelines for its conservation and the implementation of adaptive management strategies under climatic change.
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Zhang Q, Tang W, Peng S, Li Y. Limiting factors for panicle photosynthesis at the anthesis and grain filling stages in rice (Oryza sativa L.). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:77-91. [PMID: 34704647 DOI: 10.1111/tpj.15554] [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: 08/26/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
Panicle photosynthesis is crucial for grain yield in cereal crops; however, the limiting factors for panicle photosynthesis are poorly understood, greatly impeding improvement in this trait. In the present study, pot experiments were conducted to investigate the limiting factors for panicle photosynthesis at the anthesis stage in seven rice genotypes and to examine the temporal variations in photosynthesis during the grain filling stage in the Liangyou 287 genotype. At the anthesis stage, leaf and panicle photosynthesis was positively correlated with stomatal conductance and maximum carboxylation rate, which were in turn associated with hydraulic conductance and nitrogen content, respectively. Panicle hydraulic conductance was positively correlated with the area of bundle sheaths in the panicle neck. During grain filling, leaf and panicle photosynthesis remained constant at the early stage but dramatically decreased from 8 to 9 days after anthesis. The trends of variations in panicle photosynthesis were consistent with those in stomatal conductance but not with those in maximum carboxylation rate. At first, the maximum carboxylation rate and respiration rate in the panicle increased, through elevated panicle nitrogen content, but then drastically decreased, as a result of dehydration. The present study systematically investigated the limiting factors for panicle photosynthesis, which are vital for improving photosynthesis and crop yield.
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Affiliation(s)
- Qiangqiang Zhang
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Wei Tang
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Shaobing Peng
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Yong Li
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
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Magnesium Foliar Supplementation Increases Grain Yield of Soybean and Maize by Improving Photosynthetic Carbon Metabolism and Antioxidant Metabolism. PLANTS 2021; 10:plants10040797. [PMID: 33921574 PMCID: PMC8072903 DOI: 10.3390/plants10040797] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/14/2021] [Accepted: 04/15/2021] [Indexed: 12/20/2022]
Abstract
(1) Background: The aim of this study was to explore whether supplementary magnesium (Mg) foliar fertilization to soybean and maize crops established in a soil without Mg limitation can improve the gas exchange and Rubisco activity, as well as improve antioxidant metabolism, converting higher plant metabolism into grain yield. (2) Methods: Here, we tested foliar Mg supplementation in soybean followed by maize. Nutritional status of plants, photosynthesis, PEPcase and Rubisco activity, sugar concentration on leaves, oxidative stress, antioxidant metabolism, and finally the crops grain yields were determined. (3) Results: Our results demonstrated that foliar Mg supplementation increased the net photosynthetic rate and stomatal conductance, and reduced the sub-stomatal CO2 concentration and leaf transpiration by measuring in light-saturated conditions. The improvement in photosynthesis (gas exchange and Rubisco activity) lead to an increase in the concentration of sugar in the leaves before grain filling. In addition, we also confirmed that foliar Mg fertilization can improve anti-oxidant metabolism, thereby reducing the environmental stress that plants face during their crop cycle in tropical field conditions. (4) Conclusions: Our research brings the new glimpse of foliar Mg fertilization as a strategy to increase the metabolism of crops, resulting in increased grain yields. This type of biological strategy could be encouraged for wide utilization in cropping systems.
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Scudeletti D, Crusciol CAC, Bossolani JW, Moretti LG, Momesso L, Servaz Tubaña B, de Castro SGQ, De Oliveira EF, Hungria M. Trichoderma asperellum Inoculation as a Tool for Attenuating Drought Stress in Sugarcane. FRONTIERS IN PLANT SCIENCE 2021; 12:645542. [PMID: 33936132 PMCID: PMC8082249 DOI: 10.3389/fpls.2021.645542] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/15/2021] [Indexed: 05/27/2023]
Abstract
Drought stress is an important concern worldwide which reduces crop yield and quality. To alleviate this problem, Trichoderma asperellum has been used as a plant growth-promoting fungus capable of inducing plant tolerance to biotic and abiotic stresses. Here, we examined the effect of T. asperellum inoculation on sugarcane plant above and belowground development under drought stress and investigated the role of this fungus on inducing tolerance to drought at physiological and biochemical levels. The experiment was performed in pots under greenhouse conditions, with four treatments and four replicates. The treatments consisted of sugarcane plants inoculated or not with T. asperellum and grown under drought stress and adequate water availability. Drought-stressed sugarcane plants inoculated with T. asperellum changed the crop nutrition and chlorophyll and carotenoid concentrations, resulting in increased photosynthesis rate, stomatal conductance, and water use efficiency compared to the non-inoculated plants. In addition, the antioxidant metabolism also changed, increasing the superoxide dismutase and peroxidase enzyme activities, as well as the proline concentration and sugar portioning. These cascade effects enhanced the root and stalk development, demonstrating that T. asperellum inoculation is an important tool in alleviating the negative effects of drought stress in sugarcane. Future studies should be performed to elucidate if T. asperellum should be reapplied to the sugarcane ratoons.
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Affiliation(s)
- Daniele Scudeletti
- Department of Crop Science, College of Agricultural Sciences, São Paulo State University, Botucatu, Brazil
| | | | - João William Bossolani
- Department of Crop Science, College of Agricultural Sciences, São Paulo State University, Botucatu, Brazil
| | - Luiz Gustavo Moretti
- Department of Crop Science, College of Agricultural Sciences, São Paulo State University, Botucatu, Brazil
| | - Letusa Momesso
- Department of Crop Science, College of Agricultural Sciences, São Paulo State University, Botucatu, Brazil
| | - Brenda Servaz Tubaña
- School of Plant, Environmental, and Soil Sciences, LSU AgCenter, Baton Rouge, LA, United States
| | | | - Elisa Fidêncio De Oliveira
- Department of Crop Science, College of Agricultural Sciences, São Paulo State University, Botucatu, Brazil
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Cummins PL. The Coevolution of RuBisCO, Photorespiration, and Carbon Concentrating Mechanisms in Higher Plants. FRONTIERS IN PLANT SCIENCE 2021; 12:662425. [PMID: 34539685 PMCID: PMC8440988 DOI: 10.3389/fpls.2021.662425] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 07/26/2021] [Indexed: 05/20/2023]
Abstract
Ribulose-1,5-bisphosphate (RuBP) carboxylase/oxygenase (RuBisCO) is the carbon-fixing enzyme present in most photosynthetic organisms, converting CO2 into organic matter. Globally, photosynthetic efficiency in terrestrial plants has become increasingly challenged in recent decades due to a rapid increase in atmospheric CO2 and associated changes toward warmer and dryer environments. Well adapted for these new climatic conditions, the C4 photosynthetic pathway utilizes carbon concentrating mechanisms to increase CO2 concentrations surrounding RuBisCO, suppressing photorespiration from the oxygenase catalyzed reaction with O2. The energy efficiency of C3 photosynthesis, from which the C4 pathway evolved, is thought to rely critically on an uninterrupted supply of chloroplast CO2. Part of the homeostatic mechanism that maintains this constancy of supply involves the CO2 produced as a byproduct of photorespiration in a negative feedback loop. Analyzing the database of RuBisCO kinetic parameters, we suggest that in genera (Flaveria and Panicum) for which both C3 and C4 examples are available, the C4 pathway evolved only from C3 ancestors possessing much lower than the average carboxylase specificity relative to that of the oxygenase reaction (S C/O=S C/S O), and hence, the higher CO2 levels required for development of the photorespiratory CO2 pump (C2 photosynthesis) essential in the initial stages of C4 evolution, while in the later stage (final optimization phase in the Flaveria model) increased CO2 turnover may have occurred, which would have been supported by the higher CO2 levels. Otherwise, C4 RuBisCO kinetic traits remain little changed from the ancestral C3 species. At the opposite end of the spectrum, C3 plants (from Limonium) with higher than average S C/O, which may be associated with the ability of increased CO2, relative to O2, affinity to offset reduced photorespiration and chloroplast CO2 levels, can tolerate high stress environments. It is suggested that, instead of inherently constrained by its kinetic mechanism, RuBisCO possesses the extensive kinetic plasticity necessary for adaptation to changes in photorespiration that occur in the homeostatic regulation of CO2 supply under a broad range of abiotic environmental conditions.
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Emerging research in plant photosynthesis. Emerg Top Life Sci 2020; 4:137-150. [PMID: 32573736 DOI: 10.1042/etls20200035] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 12/27/2022]
Abstract
Photosynthesis involves capturing light energy and, most often, converting it to chemical energy stored as reduced carbon. It is the source of food, fuel, and fiber and there is a resurgent interest in basic research on photosynthesis. Plants make excellent use of visible light energy; leaves are ideally suited to optimize light use by having a large area per amount of material invested and also having leaf angles to optimize light utilization. It is thought that plants do not use green light but in fact they use green light better than blue light under some conditions. Leaves also have mechanisms to protect against excess light and how these work in a stochastic light environment is currently a very active area of current research. The speed at which photosynthesis can begin when leaves are first exposed to light and the speed of induction of protective mechanisms, as well as the speed at which protective mechanisms dissipate when light levels decline, have recently been explored. Research is also focused on reducing wasteful processes such as photorespiration, when oxygen instead of carbon dioxide is used. Some success has been reported in altering the path of carbon in photorespiration but on closer inspection there appears to be unforeseen effects contributing to the good news. The stoichiometry of interaction of light reactions with carbon metabolism is rigid and the time constants vary tremendously presenting large challenges to regulatory mechanisms. Regulatory mechanisms will be the topic of photosynthesis research for some time to come.
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Carriquí M, Nadal M, Clemente-Moreno MJ, Gago J, Miedes E, Flexas J. Cell wall composition strongly influences mesophyll conductance in gymnosperms. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 103:1372-1385. [PMID: 32390169 DOI: 10.1111/tpj.14806] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/22/2020] [Accepted: 04/28/2020] [Indexed: 06/11/2023]
Abstract
Cell wall thickness is widely recognized as one of the main determinants of mesophyll conductance to CO2 (gm ). However, little is known about the components that regulate effective CO2 diffusivity in the cell wall (i.e. the ratio between actual porosity and tortuosity, the other two biophysical diffusion properties of cell walls). The aim of this study was to assess, at the interspecific level, potential relationships between cell wall composition, cell wall thickness (Tcw ) and gm . Gymnosperms constitute an ideal group to deepen these relationships, as they present, on average, the thickest cell walls within spermatophytes. We characterized the foliar gas exchange, the morphoanatomical traits related with gm , the leaf fraction constituted by cell walls and three main components of primary cell walls (hemicelluloses, cellulose and pectins) in seven gymnosperm species. We found that, although the relatively low gm of gymnosperms was mainly determined by their elevated Tcw , gm was also strongly correlated with cell wall composition, which presumably sets the final effective CO2 diffusivity. The data presented here suggest that (i) differences in gm are strongly correlated to the pectins to hemicelluloses and cellulose ratio in gymnosperms, and (ii) variations in cell wall composition may modify effective CO2 diffusivity in the cell wall to compensate the negative impact of thickened walls. We speculate that higher relative pectin content allows higher gm because pectins increase cell wall hydrophilicity and CO2 molecules cross the wall dissolved in water.
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Affiliation(s)
- Marc Carriquí
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
- School of Natural Sciences, University of Tasmania (UTAS), Bag 55, Hobart, Tasmania, 7001, Australia
| | - Miquel Nadal
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
| | - María J Clemente-Moreno
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
| | - Jorge Gago
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
| | - Eva Miedes
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM, Pozuelo de Alarcón, Madrid, 28223, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Madrid, 28040, Spain
| | - Jaume Flexas
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
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