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Vega-Mas I, Ascencio-Medina E, Bozal-Leorri A, González-Murua C, Marino D, González-Moro MB. Will crops with biological nitrification inhibition capacity be favored under future atmospheric CO 2? FRONTIERS IN PLANT SCIENCE 2023; 14:1245427. [PMID: 37692431 PMCID: PMC10484480 DOI: 10.3389/fpls.2023.1245427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 08/03/2023] [Indexed: 09/12/2023]
Affiliation(s)
- Izargi Vega-Mas
- *Correspondence: Izargi Vega-Mas, ; María Begoña González-Moro,
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Weber JN, Minner-Meinen R, Behnecke M, Biedendieck R, Hänsch VG, Hercher TW, Hertweck C, van den Hout L, Knüppel L, Sivov S, Schulze J, Mendel RR, Hänsch R, Kaufholdt D. Moonlighting Arabidopsis molybdate transporter 2 family and GSH-complex formation facilitate molybdenum homeostasis. Commun Biol 2023; 6:801. [PMID: 37532778 PMCID: PMC10397214 DOI: 10.1038/s42003-023-05161-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 07/21/2023] [Indexed: 08/04/2023] Open
Abstract
Molybdenum (Mo) as essential micronutrient for plants, acts as active component of molybdenum cofactor (Moco). Core metabolic processes like nitrate assimilation or abscisic-acid biosynthesis rely on Moco-dependent enzymes. Although a family of molybdate transport proteins (MOT1) is known to date in Arabidopsis, molybdate homeostasis remained unclear. Here we report a second family of molybdate transporters (MOT2) playing key roles in molybdate distribution and usage. KO phenotype-analyses, cellular and organ-specific localization, and connection to Moco-biosynthesis enzymes via protein-protein interaction suggest involvement in cellular import of molybdate in leaves and reproductive organs. Furthermore, we detected a glutathione-molybdate complex, which reveals how vacuolar storage is maintained. A putative Golgi S-adenosyl-methionine transport function was reported recently for the MOT2-family. Here, we propose a moonlighting function, since clear evidence of molybdate transport was found in a yeast-system. Our characterization of the MOT2-family and the detection of a glutathione-molybdate complex unveil the plant-wide way of molybdate.
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Affiliation(s)
- Jan-Niklas Weber
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Rieke Minner-Meinen
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Maria Behnecke
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Rebekka Biedendieck
- Institute of Microbiology and Braunschweig Integrated Centre of Systems Biology, Technische Universität Braunschweig, Rebenring 56, D-38106, Braunschweig, Germany
| | - Veit G Hänsch
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Research and Infection Biology (HKI), Beutenbergstrasse 11a, Faculty of Biological Sciences, Friedrich Schiller University Jena, D-07743, Jena, Germany
| | - Thomas W Hercher
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Research and Infection Biology (HKI), Beutenbergstrasse 11a, Faculty of Biological Sciences, Friedrich Schiller University Jena, D-07743, Jena, Germany
| | - Lena van den Hout
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Lars Knüppel
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Simon Sivov
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Jutta Schulze
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Ralf-R Mendel
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
| | - Robert Hänsch
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany.
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, , Southwest University, Tiansheng Road No. 2, 400715, Chongqing, Beibei District, PR China.
| | - David Kaufholdt
- Institute of Plant Biology, Technische Universität Braunschweig, Humboldtstrasse 1, D-38106, Braunschweig, Germany
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Pan Y, Han X, Xu H, Wu W, Liu X, Li Y, Xue C. Elevated atmospheric CO 2 delays the key timing for split N applications to improve wheat ( Triticum aestivum L.) protein composition. FRONTIERS IN PLANT SCIENCE 2023; 14:1186890. [PMID: 37409303 PMCID: PMC10318929 DOI: 10.3389/fpls.2023.1186890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 05/26/2023] [Indexed: 07/07/2023]
Abstract
Late stage nitrogen (N) applications following basic fertilization are commonly used to ensure grain yield and increase grain protein content in wheat. Split N applications at the late growth stage of wheat are an effective measure to improve N absorption and transport and thus increase grain protein content. However, whether split N applications can alleviate the decrease in grain protein content induced by elevated atmospheric CO2 concentrations (e[CO2]) remains unclear. In the present study, a free-air CO2 enrichment system was used to investigate the effects of split N applications (at booting or anthesis) on grain yield, N utilization, protein content, and the composition of wheat under atmospheric (ACO2; 400 ± 15 ppm) and elevated CO2 concentrations (ECO2; 600 ± 15 ppm). The results showed that wheat grain yield and grain N uptake increased by 5.0% (being grains per ear by 3.0%, 1000-grain weight by 2.0%, and harvest index by 1.6%) and 4.3%, respectively, whereas grain protein content decreased by 2.3% under ECO2 conditions. Although the negative effect of e[CO2] on grain protein content was not alleviated by split N applications, gluten protein content was enhanced due to the alteration of N distribution in different protein fractions (albumins, globulins, gliadins, and glutenins). Compared to that without split N applications, the gluten content of wheat grains increased by 4.2% and 4.5% when late stage N was applied at the booting stage under ACO2 and anthesis under ECO2 conditions, respectively. The results indicate that rational handling of N fertilizers may be a promising approach to coordinating grain yield and quality under the effects of future climate change. However, compared to ACO2 conditions, the key timing for improving grain quality by split N applications should be postponed from the booting stage to anthesis under e[CO2] conditions.
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Affiliation(s)
- Yue Pan
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory for Farmland Eco-Environment of Hebei/College of Resources and Environmental Science, Hebei Agricultural University, Baoding, China
| | - Xue Han
- Key Laboratory of Agro-environment and Climate Change of Agriculture Ministry, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Huasen Xu
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory for Farmland Eco-Environment of Hebei/College of Resources and Environmental Science, Hebei Agricultural University, Baoding, China
| | - Wei Wu
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory for Farmland Eco-Environment of Hebei/College of Resources and Environmental Science, Hebei Agricultural University, Baoding, China
| | - Xiaoming Liu
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory for Farmland Eco-Environment of Hebei/College of Resources and Environmental Science, Hebei Agricultural University, Baoding, China
| | - Yingchun Li
- Key Laboratory of Agro-environment and Climate Change of Agriculture Ministry, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Cheng Xue
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory for Farmland Eco-Environment of Hebei/College of Resources and Environmental Science, Hebei Agricultural University, Baoding, China
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Gojon A, Cassan O, Bach L, Lejay L, Martin A. The decline of plant mineral nutrition under rising CO 2: physiological and molecular aspects of a bad deal. TRENDS IN PLANT SCIENCE 2023; 28:185-198. [PMID: 36336557 DOI: 10.1016/j.tplants.2022.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 09/13/2022] [Accepted: 09/28/2022] [Indexed: 05/26/2023]
Abstract
The elevation of atmospheric CO2 concentration has a strong impact on the physiology of C3 plants, far beyond photosynthesis and C metabolism. In particular, it reduces the concentrations of most mineral nutrients in plant tissues, posing major threats on crop quality, nutrient cycles, and carbon sinks in terrestrial agro-ecosystems. The causes of the detrimental effect of high CO2 levels on plant mineral status are not understood. We provide an update on the main hypotheses and review the increasing evidence that, for nitrogen, this detrimental effect is associated with direct inhibition of key mechanisms of nitrogen uptake and assimilation. We also mention promising strategies for identifying genotypes that will maintain robust nutrient status in a future high-CO2 world.
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Affiliation(s)
- Alain Gojon
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France
| | - Océane Cassan
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France
| | - Liên Bach
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France
| | - Laurence Lejay
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France
| | - Antoine Martin
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France.
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Physiological Importance of Molybdate Transporter Family 1 in Feeding the Molybdenum Cofactor Biosynthesis Pathway in Arabidopsis thaliana. Molecules 2022; 27:molecules27103158. [PMID: 35630635 PMCID: PMC9147641 DOI: 10.3390/molecules27103158] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/09/2022] [Accepted: 05/12/2022] [Indexed: 02/04/2023] Open
Abstract
Molybdate uptake and molybdenum cofactor (Moco) biosynthesis were investigated in detail in the last few decades. The present study critically reviews our present knowledge about eukaryotic molybdate transporters (MOT) and focuses on the model plant Arabidopsis thaliana, complementing it with new experiments, filling missing gaps, and clarifying contradictory results in the literature. Two molybdate transporters, MOT1.1 and MOT1.2, are known in Arabidopsis, but their importance for sufficient molybdate supply to Moco biosynthesis remains unclear. For a better understanding of their physiological functions in molybdate homeostasis, we studied the impact of mot1.1 and mot1.2 knock-out mutants, including a double knock-out on molybdate uptake and Moco-dependent enzyme activity, MOT localisation, and protein–protein interactions. The outcome illustrates different physiological roles for Moco biosynthesis: MOT1.1 is plasma membrane located and its function lies in the efficient absorption of molybdate from soil and its distribution throughout the plant. However, MOT1.1 is not involved in leaf cell imports of molybdate and has no interaction with proteins of the Moco biosynthesis complex. In contrast, the tonoplast-localised transporter MOT1.2 exports molybdate stored in the vacuole and makes it available for re-localisation during senescence. It also supplies the Moco biosynthesis complex with molybdate by direct interaction with molybdenum insertase Cnx1 for controlled and safe sequestering.
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Ayiti OE, Babalola OO. Factors Influencing Soil Nitrification Process and the Effect on Environment and Health. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2022. [DOI: 10.3389/fsufs.2022.821994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To meet the global demand for food, several factors have been deployed by agriculturists to supply plants with nitrogen. These factors have been observed to influence the soil nitrification process. Understanding the aftermath effect on the environment and health would provoke efficient management. We review literature on these factors, their aftermath effect on the environment and suggest strategies for better management. Synthetic fertilizers and chemical nitrification inhibitors are the most emphasized factors that influence the nitrification process. The process ceases when pH is <5.0. The range of temperature suitable for the proliferation of ammonia oxidizing archaea is within 30 to 37oC while that of ammonia oxidizing bacteria is within 16 to 23oC. Some of the influencing factors excessively speed up the rate of the nitrification process. This leads to excess production of nitrate, accumulation of nitrite as a result of decoupling between nitritation process and nitratation process. The inhibition mechanism of chemical nitrification inhibitors either causes a reduction in the nitrifying micro-organisms or impedes the amoA gene's function. The effects on the environment are soil acidification, global warming, and eutrophication. Some of the health effects attributed to the influence are methemoglobinemia, neurotoxicity, phytotoxicity and cancer. Biomagnification of the chemicals along the food chain is also a major concern. The use of well-researched and scientifically formulated organic fertilizers consisting of microbial inoculum, well-treated organic manure and good soil conditioner are eco-friendly. They are encouraged to be used to efficiently manage the process. Urban agriculture could promote food production, but environmental sustainability should be ensured.
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Fan J, Halpern M, Yu Y, Zuo Q, Shi J, Fan Y, Wu X, Yermiyahu U, Sheng J, Jiang P, Ben-Gal A. The Mechanisms Responsible for N Deficiency in Well-Watered Wheat Under Elevated CO 2. FRONTIERS IN PLANT SCIENCE 2022; 13:801443. [PMID: 35251079 PMCID: PMC8888439 DOI: 10.3389/fpls.2022.801443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
Elevated CO2 concentration [e(CO2)] often promotes plant growth with a decrease in tissue N concentration. In this study, three experiments, two under hydroponic and one in well-watered soil, including various levels or patterns of CO2, humidity, and N supply were conducted on wheat (Triticum aestivum L.) to explore the mechanisms of e[CO2]-induced N deficiency (ECIND). Under hydroponic conditions, N uptake remained constant even as transpiration was limited 40% by raising air relative humidity and only was reduced about 20% by supplying N during nighttime rather than daytime with a reduction of 85% in transpiration. Compared to ambient CO2 concentration, whether under hydroponic or well-watered soil conditions, and whether transpiration was kept stable or decreased to 12%, e[CO2] consistently led to more N uptake and higher biomass, while lower N concentration was observed in aboveground organs, especially leaves, as long as N supply was insufficient. These results show that, due to compensation caused by active uptake, N uptake can be uncoupled from water uptake under well-watered conditions, and changes in transpiration therefore do not account for ECIND. Similar or lower tissue NO 3 - -N concentration under e[CO2] indicated that NO 3 - assimilation was not limited and could therefore also be eliminated as a major cause of ECIND under our conditions. Active uptake has the potential to bridge the gap between N taken up passively and plant demand, but is limited by the energy required to drive it. Compared to ambient CO2 concentration, the increase in N uptake under e[CO2] failed to match the increase of carbohydrates, leading to N dilution in plant tissues, the apparent dominant mechanism explaining ECIND. Lower N concentration in leaves rather than roots under e[CO2] validated that ECIND was at least partially also related to changes in resource allocation, apparently to maintain root uptake activity and prevent more serious N deficiency.
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Affiliation(s)
- Jinjie Fan
- Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, College of Land Science and Technology, China Agricultural University, Beijing, China
| | - Moshe Halpern
- Soil, Water and Environmental Sciences, Agricultural Research Organization, Gilat Research Center, Mobile Post Negev, Israel
| | - Yangliu Yu
- Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, College of Land Science and Technology, China Agricultural University, Beijing, China
| | - Qiang Zuo
- Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, College of Land Science and Technology, China Agricultural University, Beijing, China
| | - Jianchu Shi
- Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, College of Land Science and Technology, China Agricultural University, Beijing, China
- College of Resources and Environment, Xinjiang Agricultural University, Ürümqi, China
| | - Yuchuan Fan
- Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, College of Land Science and Technology, China Agricultural University, Beijing, China
| | - Xun Wu
- Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, College of Land Science and Technology, China Agricultural University, Beijing, China
| | - Uri Yermiyahu
- Soil, Water and Environmental Sciences, Agricultural Research Organization, Gilat Research Center, Mobile Post Negev, Israel
| | - Jiandong Sheng
- College of Resources and Environment, Xinjiang Agricultural University, Ürümqi, China
| | - Pingan Jiang
- College of Resources and Environment, Xinjiang Agricultural University, Ürümqi, China
| | - Alon Ben-Gal
- Soil, Water and Environmental Sciences, Agricultural Research Organization, Gilat Research Center, Mobile Post Negev, Israel
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Xie H, Shi F, Li J, Yu M, Yang X, Li Y, Fan J. The Reciprocal Effect of Elevated CO 2 and Drought on Wheat-Aphid Interaction System. FRONTIERS IN PLANT SCIENCE 2022; 13:853220. [PMID: 35909776 PMCID: PMC9330134 DOI: 10.3389/fpls.2022.853220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 06/08/2022] [Indexed: 05/13/2023]
Abstract
Due to the rising concentration of atmospheric CO2, climate change is predicted to intensify episodes of drought. However, our understanding of how combined environmental conditions, such as elevated CO2 and drought together, will influence crop-insect interactions is limited. In the present study, the direct effects of combined elevated CO2 and drought stress on wheat (Triticum aestivum) nutritional quality and insect resistance, and the indirect effects on the grain aphid (Sitobion miscanthi) performance were investigated. The results showed that, in wheat, elevated CO2 alleviated low water content caused by drought stress. Both elevated CO2 and drought promoted soluble sugar accumulation. However, opposite effects were found on amino acid content-it was decreased by elevated CO2 and increased by drought. Further, elevated CO2 down-regulated the jasmonic acid (JA) -dependent defense, but up-regulated the salicylic acid (SA)-dependent defense. Meanwhile, drought enhanced abscisic acid accumulation that promoted the JA-dependent defense. For aphids, their feeding always induced phytohormone resistance in wheat under either elevated CO2 or drought conditions. Similar aphid performance between the control and the combined two factors were observed. We concluded that the aphid damage suffered by wheat in the future under combined elevated CO2 and drier conditions tends to maintain the status quo. We further revealed the mechanism by which it happened from the aspects of wheat water content, nutrition, and resistance to aphids.
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Affiliation(s)
- Haicui Xie
- Hebei Key Laboratory of Crop Stress Biology, College of Agronomy and Biotechnology, Hebei Normal University of Science and Technology, Qinhuangdao, China
| | - Fengyu Shi
- Hebei Key Laboratory of Crop Stress Biology, College of Agronomy and Biotechnology, Hebei Normal University of Science and Technology, Qinhuangdao, China
| | - Jingshi Li
- Hebei Key Laboratory of Crop Stress Biology, College of Agronomy and Biotechnology, Hebei Normal University of Science and Technology, Qinhuangdao, China
| | - Miaomiao Yu
- Hebei Key Laboratory of Crop Stress Biology, College of Agronomy and Biotechnology, Hebei Normal University of Science and Technology, Qinhuangdao, China
- The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xuetao Yang
- Hebei Key Laboratory of Crop Stress Biology, College of Agronomy and Biotechnology, Hebei Normal University of Science and Technology, Qinhuangdao, China
| | - Yun Li
- Hebei Key Laboratory of Crop Stress Biology, College of Agronomy and Biotechnology, Hebei Normal University of Science and Technology, Qinhuangdao, China
| | - Jia Fan
- The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- *Correspondence: Jia Fan
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9
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Gao Y, Persson DP, Vincze E, Schjoerring JK. Modification of storage proteins in the barley grain increases endosperm zinc and iron under both normal and elevated atmospheric CO 2. PHYSIOLOGIA PLANTARUM 2022; 174:e13624. [PMID: 35023171 PMCID: PMC9303220 DOI: 10.1111/ppl.13624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/16/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
Increasing atmospheric CO2 concentration is expected to enhance the grain yield of C3 cereal plants, while at the same time reducing the concentrations of minerals and proteins. This will lead to a lower nutritional quality and increase global problems associated with micronutrient malnutrition. Among the barley grain storage proteins, the C-hordein fraction has the lowest abundance of sulfur (S) containing amino acids and is poorest in binding of zinc (Zn). In the present study, C-hordein-suppressed barley lines with reduced C-hordein content, obtained by use of antisense or RNAi technology, were investigated under ambient and elevated atmospheric CO2 concentration. Grains of the C-hordein-suppressed lines showed 50% increase in the concentrations of Zn and iron (Fe) in the core endosperm relative to the wild-type under both ambient and elevated atmospheric CO2 . Element distribution images obtained using laser ablation-inductively coupled plasma-mass spectrometry confirmed the enrichment of Fe and Zn in the core endosperm of the lines with modified storage protein composition. We conclude that modification of grain storage proteins may improve the nutritional value of cereal grain with respect to Zn and Fe under both normal and future conditions of elevated atmospheric CO2 .
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Affiliation(s)
- Yajie Gao
- Department of Plant and Environmental Sciences, Faculty of ScienceUniversity of CopenhagenFrederiksbergDenmark
| | - Daniel P. Persson
- Department of Plant and Environmental Sciences, Faculty of ScienceUniversity of CopenhagenFrederiksbergDenmark
| | - Eva Vincze
- Department of Agroecology, Faculty of Science and Technology, Research Centre FlakkebjergAarhus UniversitySlagelseDenmark
| | - Jan K. Schjoerring
- Department of Plant and Environmental Sciences, Faculty of ScienceUniversity of CopenhagenFrederiksbergDenmark
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10
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Xu ZM, Wang JF, Li WL, Wang YF, He T, Wang FP, Lu ZY, Li QS. Nitrogen fertilizer affects rhizosphere Cd re-mobilization by mediating gene AmALM2 and AmALMT7 expression in edible amaranth roots. JOURNAL OF HAZARDOUS MATERIALS 2021; 418:126310. [PMID: 34130167 DOI: 10.1016/j.jhazmat.2021.126310] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/11/2021] [Accepted: 06/01/2021] [Indexed: 06/12/2023]
Abstract
In-situ stabilization of Cd-contaminated farmland is a commonly used remediation technology. Yet, rhizosphere metabolites (e.g., organic acids) during crop cultivation may cause Cd re-mobilization and over-accumulation. Here, we identified four pivotal cytomembrane-localized genes underlying Cd accumulation difference between two contrasting edible amaranth cultivars based on root gene expression profile, studied their subcellular localization and functional characteristics, and then investigated effects of nitrogen fertilizer on their expression and rhizosphere Cd re-mobilization. Results showed that more Cd accumulated by edible amaranth was due to rhizosphere Cd mobilization by mediating high expression of AmALMT2 and AmALMT7 genes, not Cd transporters in roots. This was confirmed by heterologous expression of AmALMT2 and AmALMT7 genes in Arabidopsis thaliana, since they mediated malic, fumaric, succinic, and aspartic acids efflux. Furthermore, nitrogen influencing rhizosphere acidification might be closely associated with organic acids efflux genes. Compared with N-NO3- application, N-NH4+ was massively assimilated into glutamates and oxaloacetates through up-regulating glutamine synthetase and alanine-aspartate-glutamate metabolic pathways, thereby enhancing TCA cycle and organic acids efflux dominated by binary carboxylic acids via up-regulating AmALMT2 and AmALMT7 genes, which finally caused Cd re-mobilization. Therefore, N-NO3--dominated nitrogen retarded rhizosphere Cd re-mobilization via inhibiting organic acids efflux function of AmALMT2 and AmALMT7 proteins.
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Affiliation(s)
- Zhi-Min Xu
- Key Laboratory of Environmental Pollution and Health of Guangdong Province, School of Environment, Jinan University, Guangzhou 510632, China; Engineering and Technology Research Center for Agricultural Land Pollution Prevention and Control of Guangdong Higher Education Institutes, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Jun-Feng Wang
- Key Laboratory of Environmental Pollution and Health of Guangdong Province, School of Environment, Jinan University, Guangzhou 510632, China
| | - Wan-Li Li
- Key Laboratory of Environmental Pollution and Health of Guangdong Province, School of Environment, Jinan University, Guangzhou 510632, China
| | - Yi-Fan Wang
- Key Laboratory of Environmental Pollution and Health of Guangdong Province, School of Environment, Jinan University, Guangzhou 510632, China; Department of Biotechnology, The University of Tokyo, Tokyo 113-8657, Japan
| | - Tao He
- Key Laboratory of Environmental Pollution and Health of Guangdong Province, School of Environment, Jinan University, Guangzhou 510632, China
| | - Fo-Peng Wang
- Key Laboratory of Environmental Pollution and Health of Guangdong Province, School of Environment, Jinan University, Guangzhou 510632, China
| | - Zi-Yan Lu
- Engineering and Technology Research Center for Agricultural Land Pollution Prevention and Control of Guangdong Higher Education Institutes, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Qu-Sheng Li
- Key Laboratory of Environmental Pollution and Health of Guangdong Province, School of Environment, Jinan University, Guangzhou 510632, China.
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11
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Ainsworth EA, Long SP. 30 years of free-air carbon dioxide enrichment (FACE): What have we learned about future crop productivity and its potential for adaptation? GLOBAL CHANGE BIOLOGY 2021; 27:27-49. [PMID: 33135850 DOI: 10.1111/gcb.15375] [Citation(s) in RCA: 121] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 09/17/2020] [Accepted: 09/22/2020] [Indexed: 05/03/2023]
Abstract
Free-air CO2 enrichment (FACE) allows open-air elevation of [CO2 ] without altering the microclimate. Its scale uniquely supports simultaneous study from physiology and yield to soil processes and disease. In 2005 we summarized results of then 28 published observations by meta-analysis. Subsequent studies have combined FACE with temperature, drought, ozone, and nitrogen treatments. Here, we summarize the results of now almost 250 observations, spanning 14 sites and five continents. Across 186 independent studies of 18 C3 crops, elevation of [CO2 ] by ca. 200 ppm caused a ca. 18% increase in yield under non-stress conditions. Legumes and root crops showed a greater increase and cereals less. Nitrogen deficiency reduced the average increase to 10%, as did warming by ca. 2°C. Two conclusions of the 2005 analysis were that C4 crops would not be more productive in elevated [CO2 ], except under drought, and that yield responses of C3 crops were diminished by nitrogen deficiency and wet conditions. Both stand the test of time. Further studies of maize and sorghum showed no yield increase, except in drought, while soybean productivity was negatively affected by early growing season wet conditions. Subsequent study showed reduced levels of nutrients, notably Zn and Fe in most crops, and lower nitrogen and protein in the seeds of non-leguminous crops. Testing across crop germplasm revealed sufficient variation to maintain nutrient content under rising [CO2 ]. A strong correlation of yield response under elevated [CO2 ] to genetic yield potential in both rice and soybean was observed. Rice cultivars with the highest yield potential showed a 35% yield increase in elevated [CO2 ] compared to an average of 14%. Future FACE experiments have the potential to develop cultivars and management strategies for co-promoting sustainability and productivity under future elevated [CO2 ].
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Affiliation(s)
- Elizabeth A Ainsworth
- USDA ARS Global Change and Photosynthesis Research Unit, Urbana, IL, USA
- Departments of Plant Biology and of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Stephen P Long
- Departments of Plant Biology and of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
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Wang F, Gao J, Yong JWH, Wang Q, Ma J, He X. Higher Atmospheric CO 2 Levels Favor C 3 Plants Over C 4 Plants in Utilizing Ammonium as a Nitrogen Source. FRONTIERS IN PLANT SCIENCE 2020; 11:537443. [PMID: 33343587 PMCID: PMC7738331 DOI: 10.3389/fpls.2020.537443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 11/05/2020] [Indexed: 06/12/2023]
Abstract
Photosynthesis of wheat and maize declined when grown with NH4 + as a nitrogen (N) source at ambient CO2 concentration compared to those grown with a mixture of NO3 - and NH4 +, or NO3 - as the sole N source. Interestingly, these N nutritional physiological responses changed when the atmospheric CO2 concentration increases. We studied the photosynthetic responses of wheat and maize growing with various N forms at three levels of growth CO2 levels. Hydroponic experiments were carried out using a C3 plant (wheat, Triticum aestivum L. cv. Chuanmai 58) and a C4 plant (maize, Zea mays L. cv. Zhongdan 808) given three types of N nutrition: sole NO3 - (NN), sole NH4 + (AN) and a mixture of both NO3 - and NH4 + (Mix-N). The test plants were grown using custom-built chambers where a continuous and desired atmospheric CO2 (C a ) concentration could be maintained: 280 μmol mol-1 (representing the pre-Industrial Revolution CO2 concentration of the 18th century), 400 μmol mol-1 (present level) and 550 μmol mol-1 (representing the anticipated futuristic concentration in 2050). Under AN, the decrease in net photosynthetic rate (P n ) was attributed to a reduction in the maximum RuBP-regeneration rate, which then caused reductions in the maximum Rubisco-carboxylation rates for both species. Decreases in electron transport rate, reduction of electron flux to the photosynthetic carbon [Je(PCR)] and electron flux for photorespiratory carbon oxidation [Je(PCO)] were also observed under AN for both species. However, the intercellular (C i ) and chloroplast (C c ) CO2 concentration increased with increasing atmospheric CO2 in C3 wheat but not in C4 maize, leading to a higher Je(PCR)/ Je(PCO) ratio. Interestingly, the reduction of P n under AN was relieved in wheat through higher CO2 levels, but that was not the case in maize. In conclusion, elevating atmospheric CO2 concentration increased C i and C c in wheat, but not in maize, with enhanced electron fluxes towards photosynthesis, rather than photorespiration, thereby relieving the inhibition of photosynthesis under AN. Our results contributed to a better understanding of NH4 + involvement in N nutrition of crops growing under different levels of CO2.
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Affiliation(s)
- Feng Wang
- Institute of Environmental Resources, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
- Centre of Excellence for Soil Biology, College of Resources and Environment, Southwest University, Chongqing, China
- School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
| | - Jingwen Gao
- Institute of Environmental Resources, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
- School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
| | - Jean W. H. Yong
- School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
- Department of Biosystems and Technology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Qiang Wang
- Institute of Environmental Resources, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Junwei Ma
- Institute of Environmental Resources, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Xinhua He
- Centre of Excellence for Soil Biology, College of Resources and Environment, Southwest University, Chongqing, China
- School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
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Andrews M, Condron LM, Kemp PD, Topping JF, Lindsey K, Hodge S, Raven JA. Will rising atmospheric CO 2 concentration inhibit nitrate assimilation in shoots but enhance it in roots of C 3 plants? PHYSIOLOGIA PLANTARUM 2020; 170:40-45. [PMID: 32198758 DOI: 10.1111/ppl.13096] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/17/2020] [Indexed: 05/13/2023]
Abstract
Bloom et al. proposed that rising atmospheric CO2 concentrations 'inhibit malate production in chloroplasts and thus impede assimilation of nitrate into protein of C3 plants, a phenomenon that will strongly influence primary productivity and food security under the environmental conditions anticipated during the next few decades'. Previously we argued that the weight of evidence in the literature indicated that elevated atmospheric [CO2 ] does not inhibit NO3 - assimilation in C3 plants. New data for common bean (Phaseolus vulgaris) and wheat (Triticum aestivum) were presented that supported this view and indicated that the effects of elevated atmospheric [CO2 ] on nitrogen (N) assimilation and growth of C3 vascular plants were similar regardless of the form of N assimilated. Bloom et al. strongly criticised the arguments presented in Andrews et al. Here we respond to these criticisms and again conclude that the available data indicate that elevated atmospheric [CO2 ] does not inhibit NO3 - assimilation of C3 plants. Measurement of the partitioning of NO3 - assimilation between root and shoot of C3 species under different NO3 - supply, at ambient and elevated CO2 would determine if their NO3 - assimilation is inhibited in shoots but enhanced in roots at elevated atmospheric CO2 .
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Affiliation(s)
- Mitchell Andrews
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, 7647, New Zealand
| | - Leo M Condron
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, 7647, New Zealand
| | - Peter D Kemp
- Institute of Agriculture and Environment, Massey University, Palmerston North, New Zealand
| | - Jennifer F Topping
- The Integrative Cell Biology Laboratory, Department of Biosciences, Durham University, Durham, DH1 3LE, UK
| | - Keith Lindsey
- The Integrative Cell Biology Laboratory, Department of Biosciences, Durham University, Durham, DH1 3LE, UK
| | - Simon Hodge
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, 7647, New Zealand
| | - John A Raven
- Division of Plant Science, University of Dundee at the James Hutton Institute, Dundee, DD2 5DA, UK
- School of Plant Biology, University of Western Australia, Crawley, WA, 6009, Australia
- Climate Change Cluster, University of Technology, Sydney, NSW, 2007, Australia
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Bloom AJ, Kasemsap P, Rubio-Asensio JS. Rising atmospheric CO 2 concentration inhibits nitrate assimilation in shoots but enhances it in roots of C 3 plants. PHYSIOLOGIA PLANTARUM 2020; 168:963-972. [PMID: 31642522 DOI: 10.1111/ppl.13040] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/19/2019] [Accepted: 10/19/2019] [Indexed: 05/24/2023]
Abstract
We have proposed that rising atmospheric CO2 concentrations inhibit malate production in chloroplasts and thus impede assimilation of nitrate into protein in shoots of C3 plants, a phenomenon that will strongly influence primary productivity and food security under the environmental conditions anticipated during the next few decades. Although hundreds of studies support this proposal, several publications in 2018 and 2019 purport to present counterevidence. The following study evaluates these publications as well as presents new data that elevated CO2 enhances root nitrate assimilation in wheat and Arabidopsis while it inhibits shoot nitrate assimilation.
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Affiliation(s)
- Arnold J Bloom
- Department of Plant Sciences, University of California at Davis, Davis, CA, 95616, USA
| | - Pornpipat Kasemsap
- Department of Plant Sciences, University of California at Davis, Davis, CA, 95616, USA
| | - José S Rubio-Asensio
- Department of Irrigation, Centro de Edafología y Biología Aplicada del Segura, Murcia, Spain
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Duarte AG, Longstaffe FJ, Way DA. Nitrogen fertilisation influences low CO 2 effects on plant performance. FUNCTIONAL PLANT BIOLOGY : FPB 2020; 47:134-144. [PMID: 31902392 DOI: 10.1071/fp19151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 09/27/2019] [Indexed: 06/10/2023]
Abstract
Low atmospheric CO2 conditions prevailed for most of the recent evolutionary history of plants. Such concentrations reduce plant growth compared with modern levels, but low-CO2 effects on plant performance may also be affected by nitrogen availability, since low leaf nitrogen decreases photosynthesis, and CO2 concentrations influence nitrogen assimilation. To investigate the influence of N availability on plant performance at low CO2, we grew Elymus canadensis at ambient (~400 μmol mol-1) and subambient (~180 μmol mol-1) CO2 levels, under four N-treatments: nitrate only; ammonium only; a full and a half mix of nitrate and ammonium. Growth at low CO2 decreased biomass in the full and nitrate treatments, but not in ammonium and half plants. Low CO2 effects on photosynthetic and maximum electron transport rates were influenced by fertilisation, with photosynthesis being most strongly impacted by low CO2 in full plants. Low CO2 reduced stomatal index in half plants, suggesting that the use of this indicator in paleo-inferences can be influenced by N availability. Under low CO2 concentrations, nitrate plants discriminated more against 15N whereas half plants discriminated less against 15N compared with the full treatment, suggesting that N availability should be considered when using N isotopes as paleo-indicators.
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Affiliation(s)
- André G Duarte
- Department of Biology, The University of Western Ontario, 1151 Richmond St., N6A 3K7, London, Canada; and Corresponding author.
| | - Fred J Longstaffe
- Department of Biology, The University of Western Ontario, 1151 Richmond St., N6A 3K7, London, Canada; and Department of Earth Sciences, The University of Western Ontario, 1151 Richmond St., N6A 3K7, London, Canada
| | - Danielle A Way
- Department of Biology, The University of Western Ontario, 1151 Richmond St., N6A 3K7, London, Canada; and Nicholas School of the Environment, Duke University, 9 Circuit Dr., 27710, Durham, USA; and Present address: Division of Plant Sciences, Research School of Biology, The Australian National University, 134 Linnaeus Way, ACT 2601, Canberra, Australia
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Gao Y, de Bang TC, Schjoerring JK. Cisgenic overexpression of cytosolic glutamine synthetase improves nitrogen utilization efficiency in barley and prevents grain protein decline under elevated CO 2. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:1209-1221. [PMID: 30525274 PMCID: PMC6576097 DOI: 10.1111/pbi.13046] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 10/23/2018] [Accepted: 11/09/2018] [Indexed: 05/23/2023]
Abstract
Cytosolic glutamine synthetase (GS1) plays a central role in nitrogen (N) metabolism. The importance of GS1 in N remobilization during reproductive growth has been reported in cereal species but attempts to improve N utilization efficiency (NUE) by overexpressing GS1 have yielded inconsistent results. Here, we demonstrate that transformation of barley (Hordeum vulgare L.) plants using a cisgenic strategy to express an extra copy of native HvGS1-1 lead to increased HvGS1.1 expression and GS1 enzyme activity. GS1 overexpressing lines exhibited higher grain yields and NUE than wild-type plants when grown under three different N supplies and two levels of atmospheric CO2 . In contrast with the wild-type, the grain protein concentration in the GS1 overexpressing lines did not decline when plants were exposed to elevated (800-900 μL/L) atmospheric CO2 . We conclude that an increase in GS1 activity obtained through cisgenic overexpression of HvGS1-1 can improve grain yield and NUE in barley. The extra capacity for N assimilation obtained by GS1 overexpression may also provide a means to prevent declining grain protein levels under elevated atmospheric CO2 .
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Affiliation(s)
- Yajie Gao
- Department of Plant and Environmental SciencesFaculty of ScienceCopenhagen UniversityFrederiksbergDenmark
| | - Thomas C. de Bang
- Department of Plant and Environmental SciencesFaculty of ScienceCopenhagen UniversityFrederiksbergDenmark
| | - Jan K. Schjoerring
- Department of Plant and Environmental SciencesFaculty of ScienceCopenhagen UniversityFrederiksbergDenmark
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Pleijel H, Broberg MC, Högy P, Uddling J. Nitrogen application is required to realize wheat yield stimulation by elevated CO 2 but will not remove the CO 2 -induced reduction in grain protein concentration. GLOBAL CHANGE BIOLOGY 2019; 25:1868-1876. [PMID: 30737900 DOI: 10.1111/gcb.14586] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 01/31/2019] [Indexed: 05/03/2023]
Abstract
Elevated CO2 (eCO2 ) generally promotes increased grain yield (GY) and decreased grain protein concentration (GPC), but the extent to which these effects depend on the magnitude of fertilization remains unclear. We collected data on the eCO2 responses of GY, GPC and grain protein yield and their relationships with nitrogen (N) application rates across experimental data covering 11 field grown wheat (Triticum aestivum) cultivars studied in eight countries on four continents. The eCO2 -induced stimulation of GY increased with N application rates up to ~200 kg/ha. At higher N application, stimulation of GY by eCO2 stagnated or even declined. This was valid both when the yield stimulation was expressed as the total effect and using per ppm CO2 scaling. GPC was decreased by on average 7% under eCO2 and the magnitude of this effect did not depend on N application rate. The net effect of responses on GY and protein concentration was that eCO2 typically increased and decreased grain protein yield at N application rates below and above ~100 kg/ha respectively. We conclude that a negative effect on wheat GPC seems inevitable under eCO2 and that substantial N application rates may be required to sustain wheat protein yields in a world with rising CO2 .
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Affiliation(s)
- Håkan Pleijel
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Malin C Broberg
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Petra Högy
- Institute of Landscape and Plant Ecology, University of Hohenheim, Stuttgart, Germany
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
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Wujeska-Klause A, Crous KY, Ghannoum O, Ellsworth DS. Lower photorespiration in elevated CO 2 reduces leaf N concentrations in mature Eucalyptus trees in the field. GLOBAL CHANGE BIOLOGY 2019; 25:1282-1295. [PMID: 30788883 DOI: 10.1111/gcb.14555] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 12/12/2018] [Accepted: 12/16/2018] [Indexed: 05/24/2023]
Abstract
Rising atmospheric CO2 concentrations is expected to stimulate photosynthesis and carbohydrate production, while inhibiting photorespiration. By contrast, nitrogen (N) concentrations in leaves generally tend to decline under elevated CO2 (eCO2 ), which may reduce the magnitude of photosynthetic enhancement. We tested two hypotheses as to why leaf N is reduced under eCO2 : (a) A "dilution effect" caused by increased concentration of leaf carbohydrates; and (b) inhibited nitrate assimilation caused by reduced supply of reductant from photorespiration under eCO2 . This second hypothesis is fully tested in the field for the first time here, using tall trees of a mature Eucalyptus forest exposed to Free-Air CO2 Enrichment (EucFACE) for five years. Fully expanded young and mature leaves were both measured for net photosynthesis, photorespiration, total leaf N, nitrate ( N O 3 - ) concentrations, carbohydrates and N O 3 - reductase activity to test these hypotheses. Foliar N concentrations declined by 8% under eCO2 in new leaves, while the N O 3 - fraction and total carbohydrate concentrations remained unchanged by CO2 treatment for either new or mature leaves. Photorespiration decreased 31% under eCO2 supplying less reductant, and in situ N O 3 - reductase activity was concurrently reduced (-34%) in eCO2 , especially in new leaves during summer periods. Hence, N O 3 - assimilation was inhibited in leaves of E. tereticornis and the evidence did not support a significant dilution effect as a contributor to the observed reductions in leaf N concentration. This finding suggests that the reduction of N O 3 - reductase activity due to lower photorespiration in eCO2 can contribute to understanding how eCO2 -induced photosynthetic enhancement may be lower than previously expected. We suggest that large-scale vegetation models simulating effects of eCO2 on N biogeochemistry include both mechanisms, especially where N O 3 - is major N source to the dominant vegetation and where leaf flushing and emergence occur in temperatures that promote high photorespiration rates.
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Affiliation(s)
- Agnieszka Wujeska-Klause
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Kristine Y Crous
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Oula Ghannoum
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
- Translational Photosynthesis Centre of Excellence, Western Sydney University, Penrith, New South Wales, Australia
| | - David S Ellsworth
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
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Zörb C, Ludewig U, Hawkesford MJ. Perspective on Wheat Yield and Quality with Reduced Nitrogen Supply. TRENDS IN PLANT SCIENCE 2018; 23:1029-1037. [PMID: 30249481 PMCID: PMC6202697 DOI: 10.1016/j.tplants.2018.08.012] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 08/30/2018] [Accepted: 08/31/2018] [Indexed: 05/19/2023]
Abstract
Wheat is an important cereal crop with a high demand for nitrogen (N) fertilizer to enable the grain protein accumulation that is necessary for baking and processing quality. Here, perspectives for the development of improved wheat genotypes with higher yield stability, better grain quality, and improved N use efficiency to lower environmental impacts are discussed. The development of improved wheat genotypes, for example, genotypes that lack storage proteins that do not contribute to baking quality (e.g., by genome editing), in combination with appropriate N fertilizer management to prevent N losses into the environment underpins a novel approach to improving N use efficiency. This approach may be particularly applicable to wheats grown for animal feed, which have lower quality and functionality requirements.
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Affiliation(s)
- Christian Zörb
- Institute of Crop Science, Quality of Plant Products (340e), University of Hohenheim, 70593 Stuttgart, Schloss Westflügel, Germany.
| | - Uwe Ludewig
- Institute of Crop Science, Nutritional Crop Physiology (340h), University of Hohenheim, 70593 Stuttgart, Germany
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Uddling J, Broberg MC, Feng Z, Pleijel H. Crop quality under rising atmospheric CO 2. CURRENT OPINION IN PLANT BIOLOGY 2018; 45:262-267. [PMID: 29958824 DOI: 10.1016/j.pbi.2018.06.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 06/01/2018] [Accepted: 06/04/2018] [Indexed: 05/14/2023]
Abstract
Crops grown under elevated CO2 (eCO2) typically exhibit enhanced yields but at the same time decreased nutritional quality. The latter effect has often been explained as a growth dilution phenomenon, but this cannot be the only process involved since crop nutrient concentrations are decreased also when production is unaffected by eCO2. We review the current knowledge on eCO2 effects on crop nutritional quality with focus on the current understanding of the possible mechanisms and processes causing these effects. Emphasis is on crop nitrogen (N) and protein concentrations but effects on other nutrients and how they compare with those on N are also covered.
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Affiliation(s)
- Johan Uddling
- University of Gothenburg, Department of Biological and Environmental Sciences, P.O. Box 461, 40530 Gothenburg, Sweden.
| | - Malin C Broberg
- University of Gothenburg, Department of Biological and Environmental Sciences, P.O. Box 461, 40530 Gothenburg, Sweden
| | - Zhaozhong Feng
- Chinese Academy of Sciences, State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, College of Resources and Environment, Beijing 100049, China
| | - Håkan Pleijel
- University of Gothenburg, Department of Biological and Environmental Sciences, P.O. Box 461, 40530 Gothenburg, Sweden
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