1
|
Walker B, Schmiege SC, Sharkey TD. Re-evaluating the energy balance of the many routes of carbon flow through and from photorespiration. PLANT, CELL & ENVIRONMENT 2024; 47:3365-3374. [PMID: 38804248 DOI: 10.1111/pce.14949] [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: 12/18/2023] [Revised: 04/25/2024] [Accepted: 04/29/2024] [Indexed: 05/29/2024]
Abstract
Photorespiration is an essential process related to photosynthesis that is initiated following the oxygenation reaction catalyzed by rubisco, the initial enzyme of the Calvin-Benson-Bassham cycle. This reaction produces an inhibitory intermediate that is recycled back into the Calvin-Benson-Bassham cycle by photorespiration which requires the use of energy and the release of a portion of the carbon as CO2. The energy use and CO2 release of canonical photorespiration form a foundation for biochemical models used to describe and predict leaf carbon exchange and energy use (ATP and NAPDH). The ATP and NADPH demand of canonical photorespiration is thought to be different than that of the Calvin-Benson-Bassham cycle, requiring increased flexibility in the ratio of ATP and NADPH from the light reactions. Photorespiration requires many reactions across the chloroplasts, mitochondria and peroxisomes and involves many intermediates. Growing evidence indicates that these intermediates do not all stay in photorespiration as typically assumed and instead feed into other aspects of metabolism and leave as glycine, serine, and methylene-THF. Here we discuss how alternative flux through and from canonical photorespiration alters the ATP and NADPH requirements of metabolism following rubisco oxygenation using additional derivations of biochemical models of leaf photosynthesis and energetics. Using these new derivations, we determine that the ATP and NADPH demands of photorespiration are highly sensitive to alternative flux in ways that fundamentally changes how photorespiration contributes to the ratio of total ATP and NADPH demand. Specifically, alternative flows of carbon through photorespiration could reduce ATP and NADPH demand ratio to values below what is produced from linear electron transport.
Collapse
Affiliation(s)
- Berkley Walker
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Stephanie C Schmiege
- Plant Resilience Institute, Michigan State University, East Lansing, Michigan, USA
- Department of Biology, Western University, London, Ontario, Canada
| | - Thomas D Sharkey
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Plant Resilience Institute, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| |
Collapse
|
2
|
Leverett A, Kromdijk J. The long and tortuous path towards improving photosynthesis by engineering elevated mesophyll conductance. PLANT, CELL & ENVIRONMENT 2024; 47:3411-3427. [PMID: 38804598 DOI: 10.1111/pce.14940] [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: 11/14/2023] [Revised: 03/13/2024] [Accepted: 04/29/2024] [Indexed: 05/29/2024]
Abstract
The growing demand for global food production is likely to be a defining issue facing humanity over the next 50 years. To tackle this challenge, there is a desire to bioengineer crops with higher photosynthetic efficiencies, to increase yields. Recently, there has been a growing interest in engineering leaves with higher mesophyll conductance (gm), which would allow CO2 to move more efficiently from the substomatal cavities to the chloroplast stroma. However, if crop yield gains are to be realised through this approach, it is essential that the methodological limitations associated with estimating gm are fully appreciated. In this review, we summarise these limitations, and outline the uncertainties and assumptions that can affect the final estimation of gm. Furthermore, we critically assess the predicted quantitative effect that elevating gm will have on assimilation rates in crop species. We highlight the need for more theoretical modelling to determine whether altering gm is truly a viable route to improve crop performance. Finally, we offer suggestions to guide future research on gm, which will help mitigate the uncertainty inherently associated with estimating this parameter.
Collapse
Affiliation(s)
- Alistair Leverett
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Johannes Kromdijk
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| |
Collapse
|
3
|
Sun T, Zhang X, Lv S, Lin X, Ma J, Liu J, Fang Q, Tang L, Liu L, Cao W, Liu B, Zhu Y. Improving the predictions of leaf photosynthesis during and after short-term heat stress with current rice models. PLANT, CELL & ENVIRONMENT 2023; 46:3353-3370. [PMID: 37575035 DOI: 10.1111/pce.14683] [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: 05/31/2022] [Revised: 07/26/2023] [Accepted: 07/31/2023] [Indexed: 08/15/2023]
Abstract
In response to increasing global warming, extreme heat stress significantly alters photosynthetic production. While numerous studies have investigated the temperature effects on photosynthesis, factors like vapour pressure deficit (VPD), leaf nitrogen, and feedback of sink limitation during and after extreme heat stress remain underexplored. This study assessed photosynthesis calculations in seven rice growth models using observed maximum photosynthetic rate (Pmax ) during and after short-term extreme heat stress in multi-year environment-controlled experiments. Biochemical models (FvCB-type) outperformed light response curve-based models (LRC-type) when incorporating observed leaf nitrogen, photosynthetically active radiation, temperatures, and intercellular CO2 concentration (Ci ) as inputs. Prediction uncertainty during heat stress treatment primarily resulted from variation in temperatures and Ci . Improving FVPD (the slope for the linear effect of VPD on Ci /Ca ) to be temperature-dependent, rather than constant as in original models, significantly improved Ci prediction accuracy under heat stress. Leaf nitrogen response functions led to model variation in leaf photosynthesis predictions after heat stress, which was mitigated by calibrated nitrogen response functions based on active photosynthetic nitrogen. Additionally, accounting for observed differences in carbohydrate accumulation between panicles and stems during grain filling improved the feedback of sink limitation, reducing Ci overestimation under heat stress treatments.
Collapse
Affiliation(s)
- Ting Sun
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Specialty Agri-product Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou, Zhejiang, China
| | - Xiaohu Zhang
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Suyu Lv
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Xuanhao Lin
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Jifeng Ma
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Jiaming Liu
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Qizhao Fang
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Liang Tang
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Leilei Liu
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Weixing Cao
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Bing Liu
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Yan Zhu
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| |
Collapse
|
4
|
Abstract
Photorespiration results in a large amount of leaf photosynthesis consumption. However, there are few studies on the response of photorespiration to multi-factors. In this study, a machine learning model for the photorespiration rate of cucumber leaves’ response to multi-factors was established. It provides a theoretical basis for studies related to photorespiration. Machine learning models of different methods were designed and compared. The photorespiration rate was expressed as the difference between the photosynthetic rate at 2% O2 and 21% O2 concentrations. The results show that the XGBoost models had the best fit performance with an explained variance score of 0.970 for both photosynthetic rate datasets measured using air and 2% O2, with mean absolute errors of 0.327 and 0.181, root mean square errors of 1.607 and 1.469, respectively, and coefficients of determination of 0.970 for both. In addition, this study indicates the importance of the features of temperature, humidity and the physiological status of the leaves for predicted results of photorespiration. The model established in this study performed well, with high accuracy and generalization ability. As a preferable exploration of the research on photorespiration rate simulation, it has theoretical significance and application prospects.
Collapse
|
5
|
Osei-Bonsu I, McClain AM, Walker BJ, Sharkey TD, Kramer DM. The roles of photorespiration and alternative electron acceptors in the responses of photosynthesis to elevated temperatures in cowpea. PLANT, CELL & ENVIRONMENT 2021; 44:2290-2307. [PMID: 33555066 PMCID: PMC11176259 DOI: 10.1111/pce.14026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 11/13/2020] [Accepted: 11/20/2020] [Indexed: 05/02/2023]
Abstract
We explored the effects, on photosynthesis in cowpea (Vigna unguiculata) seedlings, of high temperature and light-environmental stresses that often co-occur under field conditions and can have greater impact on photosynthesis than either by itself. We observed contrasting responses in the light and carbon assimilatory reactions, whereby in high temperature, the light reactions were stimulated while CO2 assimilation was substantially reduced. There were two striking observations. Firstly, the primary quinone acceptor (QA ), a measure of the regulatory balance of the light reactions, became more oxidized with increasing temperature, suggesting increased electron sink capacity, despite the reduced CO2 fixation. Secondly, a strong, O2 -dependent inactivation of assimilation capacity, consistent with down-regulation of rubisco under these conditions. The dependence of these effects on CO2 , O2 and light led us to conclude that both photorespiration and an alternative electron acceptor supported increased electron flow, and thus provided photoprotection under these conditions. Further experiments showed that the increased electron flow was maintained by rapid rates of PSII repair, particularly at combined high light and temperature. Overall, the results suggest that photodamage to the light reactions can be avoided under high light and temperatures by increasing electron sink strength, even when assimilation is strongly suppressed.
Collapse
Affiliation(s)
- Isaac Osei-Bonsu
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Horticulture Division, CSIR-Crops Research Institute, Kumasi, Ghana
| | - Alan M McClain
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Berkley J Walker
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
| | - Thomas D Sharkey
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - David M Kramer
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| |
Collapse
|
6
|
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.
Collapse
|
7
|
Ye ZP, Kang HJ, An T, Duan HL, Wang FB, Yang XL, Zhou SX. Modeling Light Response of Electron Transport Rate and Its Allocation for Ribulose Biphosphate Carboxylation and Oxygenation. FRONTIERS IN PLANT SCIENCE 2020; 11:581851. [PMID: 33042194 PMCID: PMC7522219 DOI: 10.3389/fpls.2020.581851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 08/25/2020] [Indexed: 06/11/2023]
Abstract
Accurately describing the light response curve of electron transport rate (J-I curve) and allocation of electron flow for ribulose biphosphate (RuBP) carboxylation (J C-I curve) and that for oxygenation (J O-I curve) is fundamental for modeling of light relations of electron flow at the whole-plant and ecosystem scales. The non-rectangular hyperbolic model (hereafter, NH model) has been widely used to characterize light response of net photosynthesis rate (A n; A n-I curve) and J-I curve. However, NH model has been reported to overestimate the maximum A n (A nmax) and the maximum J (J max), largely due to its asymptotic function. Meanwhile, few efforts have been delivered for describing J C-I and J O-I curves. The long-standing challenge on describing A n-I and J-I curves have been resolved by a recently developed A n-I and J-I models (hereafter, Ye model), which adopt a nonasymptotic function. To test whether Ye model can resolve the challenge of NH model in reproducing J-I, J C-I and J O-I curves over light-limited, light-saturated, and photoinhibitory I levels, we compared the performances of Ye model and NH model against measurements on two C3 crops (Triticum aestivum L. and Glycine max L.) grown in field. The results showed that NH model significantly overestimated the A nmax and J max for both species, which can be accurately obtained by Ye model. Furthermore, NH model significantly overestimated the maximum electron flow for carboxylation (J C-max) but not the maximum electron flow for oxygenation (J O-max) for both species, disclosing the reason underlying the long-standing problem of NH model-overestimation of J max and A nmax.
Collapse
Affiliation(s)
- Zi-Piao Ye
- Maths and Physics College, Jinggangshan University, Ji’an, China
| | - Hua-Jing Kang
- Department of Landscape and Water Conservancy Engineering, Wenzhou Vocational College of Science and Technology, Wenzhou, China
| | - Ting An
- Maths and Physics College, Jinggangshan University, Ji’an, China
| | - Hong-Lang Duan
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, China
| | - Fu-Biao Wang
- Maths and Physics College, Jinggangshan University, Ji’an, China
| | - Xiao-Long Yang
- Maths and Physics College, Jinggangshan University, Ji’an, China
| | - Shuang-Xi Zhou
- The New Zealand Institute for Plant and Food Research Limited, Hawke’s Bay, New Zealand
| |
Collapse
|
8
|
Busch FA. Photorespiration in the context of Rubisco biochemistry, CO 2 diffusion and metabolism. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:919-939. [PMID: 31910295 DOI: 10.1111/tpj.14674] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 12/20/2019] [Accepted: 01/03/2020] [Indexed: 05/11/2023]
Abstract
Photorespiratory metabolism is essential for plants to maintain functional photosynthesis in an oxygen-containing environment. Because the oxygenation reaction of Rubisco is followed by the loss of previously fixed carbon, photorespiration is often considered a wasteful process and considerable efforts are aimed at minimizing the negative impact of photorespiration on the plant's carbon uptake. However, the photorespiratory pathway has also many positive aspects, as it is well integrated within other metabolic processes, such as nitrogen assimilation and C1 metabolism, and it is important for maintaining the redox balance of the plant. The overall effect of photorespiratory carbon loss on the net CO2 fixation of the plant is also strongly influenced by the physiology of the leaf related to CO2 diffusion. This review outlines the distinction between Rubisco oxygenation and photorespiratory CO2 release as a basis to evaluate the costs and benefits of photorespiration.
Collapse
Affiliation(s)
- Florian A Busch
- Research School of Biology and ARC Centre of Excellence for Translational Photosynthesis, Australian National University, Acton, ACT, 2601, Australia
| |
Collapse
|
9
|
South PF, Cavanagh AP, Liu HW, Ort DR. Synthetic glycolate metabolism pathways stimulate crop growth and productivity in the field. Science 2019; 363:eaat9077. [PMID: 30606819 PMCID: PMC7745124 DOI: 10.1126/science.aat9077] [Citation(s) in RCA: 324] [Impact Index Per Article: 64.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 11/20/2018] [Indexed: 01/06/2023]
Abstract
Photorespiration is required in C3 plants to metabolize toxic glycolate formed when ribulose-1,5-bisphosphate carboxylase-oxygenase oxygenates rather than carboxylates ribulose-1,5-bisphosphate. Depending on growing temperatures, photorespiration can reduce yields by 20 to 50% in C3 crops. Inspired by earlier work, we installed into tobacco chloroplasts synthetic glycolate metabolic pathways that are thought to be more efficient than the native pathway. Flux through the synthetic pathways was maximized by inhibiting glycolate export from the chloroplast. The synthetic pathways tested improved photosynthetic quantum yield by 20%. Numerous homozygous transgenic lines increased biomass productivity by >40% in replicated field trials. These results show that engineering alternative glycolate metabolic pathways into crop chloroplasts while inhibiting glycolate export into the native pathway can drive increases in C3 crop yield under agricultural field conditions.
Collapse
Affiliation(s)
- Paul F South
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | - Amanda P Cavanagh
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | - Helen W Liu
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA
| | - Donald R Ort
- Global Change and Photosynthesis Research Unit, United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801, USA.
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA
- Department of Plant Biology, University of Illinois, Urbana, IL 61801, USA
| |
Collapse
|
10
|
Ploschuk RA, Miralles DJ, Colmer TD, Ploschuk EL, Striker GG. Waterlogging of Winter Crops at Early and Late Stages: Impacts on Leaf Physiology, Growth and Yield. FRONTIERS IN PLANT SCIENCE 2018; 9:1863. [PMID: 30619425 PMCID: PMC6306497 DOI: 10.3389/fpls.2018.01863] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 12/03/2018] [Indexed: 05/20/2023]
Abstract
Waterlogging is expected to increase as a consequence of global climate change, constraining crop production in various parts of the world. This study assessed tolerance to 14-days of early- or late-stage waterlogging of the major winter crops wheat, barley, rapeseed and field pea. Aerenchyma formation in adventitious roots, leaf physiological parameters (net photosynthesis, stomatal and mesophyll conductances, chlorophyll fluorescence), shoot and root growth during and after waterlogging, and seed production were evaluated. Wheat produced adventitious roots with 20-22% of aerenchyma, photosynthesis was maintained during waterlogging, and seed production was 86 and 71% of controls for early- and late-waterlogging events. In barley and rapeseed, plants were less affected by early- than by late-waterlogging. Barley adventitious roots contained 19% aerenchyma, whereas rapeseed did not form aerenchyma. In barley, photosynthesis was reduced during early-waterlogging mainly by stomatal limitations, and by non-stomatal constraints (lower mesophyll conductance and damage to photosynthetic apparatus as revealed by chlorophyll fluorescence) during late-waterlogging. In rapeseed, photosynthesis was mostly reduced by non-stomatal limitations during early- and late-waterlogging, which also impacted shoot and root growth. Early-waterlogged plants of both barley and rapeseed were able to recover in growth upon drainage, and seed production reached ca. 79-85% of the controls, while late-waterlogged plants only attained 26-32% in seed production. Field pea showed no ability to develop root aerenchyma when waterlogged, and its photosynthesis (and stomatal and mesophyll conductances) was rapidly decreased by the stress. Consequently, waterlogging drastically reduced field pea seed production to 6% of controls both at early- and late-stages with plants being unable to resume growth upon drainage. In conclusion, wheat generates a set of adaptive responses to withstand 14 days of waterlogging, barley and rapeseed can still produce significant yield if transiently waterlogged during early plant stages but are more adversely impacted at the late stage, and field pea is not suitable for areas prone to waterlogging events of 14 days at either growth stage.
Collapse
Affiliation(s)
| | - Daniel Julio Miralles
- IFEVA, Facultad de Agronomía, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | - Timothy David Colmer
- Faculty of Science, School of Agriculture and Environment, The University of Western Australia, Crawley, WA, Australia
| | - Edmundo Leonardo Ploschuk
- Facultad de Agronomía, Cátedra de Cultivos Industriales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gustavo Gabriel Striker
- IFEVA, Facultad de Agronomía, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
- Faculty of Science, School of Agriculture and Environment, The University of Western Australia, Crawley, WA, Australia
| |
Collapse
|
11
|
Bloom AJ, Lancaster KM. Manganese binding to Rubisco could drive a photorespiratory pathway that increases the energy efficiency of photosynthesis. NATURE PLANTS 2018; 4:414-422. [PMID: 29967515 DOI: 10.1038/s41477-018-0191-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 06/01/2018] [Indexed: 05/18/2023]
Abstract
Most plants, contrary to popular belief, do not waste over 30% of their photosynthate in a futile cycle called photorespiration. Rather, the photorespiratory pathway generates additional malate in the chloroplast that empowers many energy-intensive chemical reactions, such as those involved in nitrate assimilation. Thus, the balance between carbon fixation and photorespiration determines the plant carbon-nitrogen balance and protein concentrations. Plant protein concentrations, in turn, depend not only on the relative concentrations of carbon dioxide and oxygen in the chloroplast but also on the relative activities of magnesium and manganese, which are metals that associate with several key enzymes in the photorespiratory pathway and alter their function. Understanding the regulation of these processes is critical for sustaining food quality under rising CO2 atmospheres.
Collapse
Affiliation(s)
- Arnold J Bloom
- Department of Plant Sciences, University of California at Davis, Davis, CA, USA.
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| |
Collapse
|