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Liu Z, Cheng J. C 4 rice engineering, beyond installing a C 4 cycle. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 206:108256. [PMID: 38091938 DOI: 10.1016/j.plaphy.2023.108256] [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: 04/06/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 02/15/2024]
Abstract
C4 photosynthesis in higher plants is carried out by two distinct cell types: mesophyll cells and bundle sheath cells, as a result highly concentrated carbon dioxide is released surrounding RuBisCo in chloroplasts of bundle sheath cells and the photosynthetic efficiency is significantly higher than that of C3 plants. The evolution of the dual-cell C4 cycle involved complex modifications to leaf anatomy and cell ultra-structures. These include an increase in leaf venation, the formation of Kranz anatomy, changes in chloroplast morphology in bundle sheath cells, and increases in the density of plasmodesmata at interfaces between the bundle sheath and mesophyll cells. It is predicted that cereals will be in severe worldwide shortage at the mid-term of this century. Rice is a staple food that feeds more than half of the world's population. If rice can be engineered to perform C4 photosynthesis, it is estimated that rice yield will be increased by at least 50% due to enhanced photosynthesis. Thus, the Second Green Revolution has been launched on this principle by genetically installing C4 photosynthesis into C3 crops. The studies on molecular mechanisms underlying the changes in leaf morphoanatomy involved in C4 photosynthesis have made great progress in recent years. As there are plenty of reviews discussing the installment of the C4 cycle, we focus on the current progress and challenges posed to the research regarding leaf anatomy and cell ultra-structure modifications made towards the development of C4 rice.
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Affiliation(s)
- Zheng Liu
- State Key Laboratory of North China Crop Improvement and Regulation, College of Agronomy, Hebei Agricultural University, Baoding, 071001, China.
| | - Jinjin Cheng
- College of Agronomy, Shanxi Agricultural University, Jinzhong, 030801, China
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Huang G, Zeng Y. Increased stomatal conductance and leaf biochemical capacity, not mesophyll conductance, contributing to the enhanced photosynthesis in Oryza plants during domestication. PLANTA 2023; 259:28. [PMID: 38127197 DOI: 10.1007/s00425-023-04305-x] [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: 10/08/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023]
Abstract
MAIN CONCLUSION Leaf biochemical capacity and the ratio of leaf biochemical capacity to stomatal conductance are promising to enhance leaf photosynthetic rate and water use efficiency in rice plants, respectively. Domestication may have great impact on crop photosynthetic rate, which has not been fully understood, especially from the perspective of stomatal conductance, mesophyll conductance, and leaf biochemical capacity simultaneously. In this study, we constructed a database consisting of 141 and 92 sets of data from wild and cultivated rice, respectively, including leaf gas exchange parameters, hydraulic conductance, structural traits, and nitrogen content. We found that, compared to wild rice, enhanced leaf photosynthetic rate in cultivated rice was mainly resulted by the increased stomatal conductance and leaf biochemical capacity, rather than mesophyll conductance. The unchanged mesophyll conductance observed during domestication suggested that it might have been optimized during plant evolution in wild rice. Additionally, the positive relationship between stomatal density and stomatal conductance disappeared in Oryza plants during domestication, suggesting that stomatal conductance in cultivated rice is less restricted by stomatal density, compared to wild rice. Moreover, in both wild and cultivated rice, leaf photosynthetic rate was mainly determined by leaf biochemical capacity, rather than stomatal conductance and mesophyll conductance. This study highlighted the important role of stomatal conductance and leaf biochemical capacity in improvement of leaf photosynthetic rate in rice during domestication. Leaf biochemical capacity and the ratio of leaf biochemical capacity to stomatal conductance should be further investigated to enhance leaf photosynthetic rate and water use efficiency in rice plants, respectively.
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Affiliation(s)
- Guanjun Huang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, School of Agricultural Sciences, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi, China.
| | - Yongjun Zeng
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, School of Agricultural Sciences, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi, China
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Zhang SY, Zhao BG, Shen Z, Mei YC, Li G, Dong FQ, Zhang J, Chao Q, Wang BC. Integrating ATAC-seq and RNA-seq to identify differentially expressed genes with chromatin-accessible changes during photosynthetic establishment in Populus leaves. PLANT MOLECULAR BIOLOGY 2023; 113:59-74. [PMID: 37634200 DOI: 10.1007/s11103-023-01375-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 08/03/2023] [Indexed: 08/29/2023]
Abstract
Leaves are the primary photosynthetic organs, providing essential substances for tree growth. It is important to obtain an anatomical understanding and regulatory network analysis of leaf development. Here, we studied leaf development in Populus Nanlin895 along a development gradient from the newly emerged leaf from the shoot apex to the sixth leaf (L1 to L6) using anatomical observations and RNA-seq analysis. It indicated that mesophyll cells possess obvious vascular, palisade, and spongy tissue with distinct intercellular spaces after L3. Additionally, vacuoles fuse while epidermal cells expand to form pavement cells. RNA-seq analysis indicated that genes highly expressed in L1 and L2 were related to cell division and differentiation, while those highly expressed in L3 were enriched in photosynthesis. Therefore, we selected L1 and L3 to integrate ATAC-seq and RNA-seq and identified 735 differentially expressed genes (DEGs) with changes in chromatin accessibility regions within their promoters, of which 87 were transcription factors (TFs), such as ABI3VP1, AP-EREBP, MYB, NAC, and GRF. Motif enrichment analysis revealed potential regulatory functions for the DEGs through upstream TFs including TCP, bZIP, HD-ZIP, Dof, BBR-BPC, and MYB. Overall, our research provides a potential molecular foundation for regulatory network exploration in leaf development during photosynthesis establishment.
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Affiliation(s)
- Sheng-Ying Zhang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Biligen-Gaowa Zhao
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhuo Shen
- Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, 150040, China
| | - Ying-Chang Mei
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guo Li
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Feng-Qin Dong
- University of Chinese Academy of Sciences, Beijing, 100049, China
- The Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Jiao Zhang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qing Chao
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Bai-Chen Wang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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Mubarak A, Burgess A, Pyke K, Quick W, Murchie E. Mass screening of rice mutant populations at low CO 2 for identification of lowered photorespiration and respiration rates. FRONTIERS IN PLANT SCIENCE 2023; 14:1125770. [PMID: 36938057 PMCID: PMC10020370 DOI: 10.3389/fpls.2023.1125770] [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: 12/16/2022] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
INTRODUCTION Identifying rice (Oryza sativa) germplasm with improved efficiency of primary metabolism is of utmost importance in order to increase yields. One such approach can be attained through screening genetically diverse populations under altered environmental conditions. Growth or treatment under low carbon dioxide (CO2) concentrations can be used as a means of revealing altered leaf photorespiration, respiration and other metabolic variants. METHODS We developed a pipeline for very high throughput treatment of gamma- and ethyl methanesulfonate- (EMS) induced mutant populations of IR64 rice seedlings at very low CO2 for 7 days. 1050 seedlings per batch at 5th leaf stage were exposed to 60 ppm CO2 for the first day and 30 ppm for the remaining three days. Following this, putative candidates were identified by measuring chlorophyll depletion using SPAD. Screening results showed a distinct difference between the mutants and the WTs. RESULTS AND DISCUSSION The mean chlorophyll loss in WTs ranged from 65% to 11% respectively, whereas in the mutant lines chlorophyll loss ranged from 0 to 100%, suggesting considerable phenotypic variation. Rice mutants with a reduced chlorophyll reduction (<10%) were identified as 'Chlorophyll retention mutants' (CRMs) under low CO2 stress. In total, 1909 mutant lines (14,000 seedlings) were screened for chlorophyll content under 30 ppm CO2, with 26 lines selected for detailed screening. These 26 putative candidates were self-seeded to produce an M5 generation, used to determine the genetic control of the altered response to low CO2. Gas exchange of light and CO2 response revealed that there were significant variations among photosynthetic properties in two selected rice mutants. The CO2 compensation points in the absence of photorespiration and leaf respiration rates were lower than the WTs and anatomical analyses showed that CRM 29 had improved mesophyll cell area. We propose that this approach is useful for generating new material for breeding rice with improved primary metabolism.
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Affiliation(s)
- A.N.M. Mubarak
- Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Leicestershire, United Kingdom
- Department of Biosystems Technology, Faculty of Technology, South Eastern University of Sri Lanka, University Park, Oluvil, Sri Lanka
- International Rice Research Institute, Los Baños, Laguna, Philippines
| | - A.J. Burgess
- Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Leicestershire, United Kingdom
| | - K. Pyke
- Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Leicestershire, United Kingdom
| | - W.P. Quick
- International Rice Research Institute, Los Baños, Laguna, Philippines
| | - E.H. Murchie
- Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Leicestershire, United Kingdom
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Mubarak ANM, Mufeeth Mohammathu MM, Kumara ADNT. Will future maize improvement programs leverage the canopy light-interception, photosynthetic, and biomass capacities of traditional accessions? PeerJ 2023; 11:e15233. [PMID: 37131994 PMCID: PMC10149054 DOI: 10.7717/peerj.15233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 03/24/2023] [Indexed: 05/04/2023] Open
Abstract
Maize germplasm has greater latent potential to address the global food and feed crisis because of its high radiation, water and nutrient efficiencies. Photosynthetic and canopy architectural traits in maize are important in determining yield. The present study aimed to screen a subset of local maize accessions in Sri Lanka to evaluate their photosynthetic, biomass and yield related traits and to identify resource efficient germplasm. Experiments were carried out in the Ampara district of Sri Lanka. Eight maize accessions viz; SEU2, SEU6, SEU9, SEU10, SEU14, SEU15, SEU17 and SEU17 and two elite F1 cultivars (cv. Pacific-999 and cv. Bhadra) were analyzed under field conditions. Our results showed that maize genotypes produced a lower leaf area index (LAI) at the third and tenth week after field planting (WAP). However, the LAI was significantly increased in six WAP by Pacific-999, SEU2, SEU9, and SEU15. A similar trend was observed for percentage of light interception at three WAP (47%), six WAP (>64%), and decreased at 10 WAP. In addition, LAI maximum values were between 3.0 and 3.5, allowing 80% of the incident light to be intercepted by maize canopies. The estimated light extinction coefficient (k) remained lower (<0.5), suggesting that maize leaves are eractophilic canopies. Although fractional interception (f) varies, SEU2 and SEU9 had the highest values (0.57), and quantum yields of PSII (>0.73) in dark-adapted leaves. In addition, Pacific-999, SEU2, SEU9, and SEU17 had significantly higher rates of photosynthesis with minimal stomatal conductance and transpiration rates. As a result, they outperformed the control plants in terms of biomass, cob weight and grain yield. This suggests that native maize germplasm could be introduced as novel, less resource-intensive cultivars to sustain global food security.
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Singh J, Garai S, Das S, Thakur JK, Tripathy BC. Role of C4 photosynthetic enzyme isoforms in C3 plants and their potential applications in improving agronomic traits in crops. PHOTOSYNTHESIS RESEARCH 2022; 154:233-258. [PMID: 36309625 DOI: 10.1007/s11120-022-00978-9] [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: 06/02/2022] [Accepted: 10/14/2022] [Indexed: 06/16/2023]
Abstract
As compared to C3, C4 plants have higher photosynthetic rates and better tolerance to high temperature and drought. These traits are highly beneficial in the current scenario of global warming. Interestingly, all the genes of the C4 photosynthetic pathway are present in C3 plants, although they are involved in diverse non-photosynthetic functions. Non-photosynthetic isoforms of carbonic anhydrase (CA), phosphoenolpyruvate carboxylase (PEPC), malate dehydrogenase (MDH), the decarboxylating enzymes NAD/NADP-malic enzyme (NAD/NADP-ME), and phosphoenolpyruvate carboxykinase (PEPCK), and finally pyruvate orthophosphate dikinase (PPDK) catalyze reactions that are essential for major plant metabolism pathways, such as the tricarboxylic acid (TCA) cycle, maintenance of cellular pH, uptake of nutrients and their assimilation. Consistent with this view differential expression pattern of these non-photosynthetic C3 isoforms has been observed in different tissues across the plant developmental stages, such as germination, grain filling, and leaf senescence. Also abundance of these C3 isoforms is increased considerably in response to environmental fluctuations particularly during abiotic stress. Here we review the vital roles played by C3 isoforms of C4 enzymes and the probable mechanisms by which they help plants in acclimation to adverse growth conditions. Further, their potential applications to increase the agronomic trait value of C3 crops is discussed.
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Affiliation(s)
- Jitender Singh
- National Institute of Plant Genome Research, New Delhi, 110067, India.
| | - Sampurna Garai
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Shubhashis Das
- National Institute of Plant Genome Research, New Delhi, 110067, India
| | - Jitendra Kumar Thakur
- National Institute of Plant Genome Research, New Delhi, 110067, India.
- International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.
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Sherpa R, Devadas R, Bolbhat SN, Nikam TD, Penna S. Gamma Radiation Induced In-Vitro Mutagenesis and Isolation of Mutants for Early Flowering and Phytomorphological Variations in Dendrobium 'Emma White'. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11223168. [PMID: 36432897 PMCID: PMC9697006 DOI: 10.3390/plants11223168] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/11/2022] [Accepted: 11/15/2022] [Indexed: 05/31/2023]
Abstract
In vitro mutagenesis offers a feasible approach for developing new orchid cultivars through genetic manipulation. In the present study, protocorm-like bodies (PLBs) were exposed to gamma rays (10, 20, 40, 60, 80 Gy) to study in vitro growth responses and induction of mutants in Dendrobium ‘Emma White’. Both proliferation and regeneration of PLBs decreased progressively with increasing doses, except for a significantly enhanced growth response at 10 Gy. The optimal dose of gamma radiation for mutagenesis was found in the range 10 to 25 Gy based on the growth reduction curve. Analysis using a high-throughput cell analyzer revealed a significant reduction in nuclear DNA content at > 40 Gy doses. At 10 Gy treatment, the growth attributes, such as root length, plant height and leaf number, were significantly increased by 36%, 26% and 20%, respectively, compared to the control. This increase was significant over other tested doses as well. Testing of random amplified polymorphic DNA markers revealed the presence of detectable polymorphism among gamma mutant plantlets with a polymorphism information content value at 0.41. The gamma-ray-induced earliness in flower development was observed within 294 days post ex vitro growth of 10 Gy mutant compared to the control plants flowered after 959 days. Our results highlight the significance of gamma radiation in inducing enhanced growth, morphological variations and early floral initiation in Dendrobium, providing a basic framework for mutation breeding and improvement of orchids.
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Affiliation(s)
- Rubina Sherpa
- Department of Botany, Annasaheb Awate College, Manchar 410503, India
- Indian Council of Agricultural Research-National Research Centre on Orchids, Pakyong 737106, India
| | - Ramgopal Devadas
- Indian Council of Agricultural Research-National Research Centre on Orchids, Pakyong 737106, India
| | | | | | - Suprasanna Penna
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- Amity Institute of Biotechnology, Amity University Mumbai, Mumbai 410206, India
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Shen Q, Xie Y, Qiu X, Yu J. The era of cultivating smart rice with high light efficiency and heat tolerance has come of age. FRONTIERS IN PLANT SCIENCE 2022; 13:1021203. [PMID: 36275525 PMCID: PMC9585279 DOI: 10.3389/fpls.2022.1021203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
How to improve the yield of crops has always been the focus of breeding research. Due to the population growth and global climate change, the demand for food has increased sharply, which has brought great challenges to agricultural production. In order to make up for the limitation of global cultivated land area, it is necessary to further improve the output of crops. Photosynthesis is the main source of plant assimilate accumulation, which has a profound impact on the formation of its yield. This review focuses on the cultivation of high light efficiency plants, introduces the main technical means and research progress in improving the photosynthetic efficiency of plants, and discusses the main problems and difficulties faced by the cultivation of high light efficiency plants. At the same time, in view of the frequent occurrence of high-temperature disasters caused by global warming, which seriously threatened plant normal production, we reviewed the response mechanism of plants to heat stress, introduced the methods and strategies of how to cultivate heat tolerant crops, especially rice, and briefly reviewed the progress of heat tolerant research at present. Given big progress in these area, the era of cultivating smart rice with high light efficiency and heat tolerance has come of age.
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Affiliation(s)
- Qiuping Shen
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang A & F University, Hangzhou, China
- College of Advanced Agricultural Sciences, Zhejiang A & F University, Hangzhou, China
| | - Yujun Xie
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang A & F University, Hangzhou, China
- College of Advanced Agricultural Sciences, Zhejiang A & F University, Hangzhou, China
| | - Xinzhe Qiu
- College of Advanced Agricultural Sciences, Zhejiang A & F University, Hangzhou, China
| | - Jinsheng Yu
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, Zhejiang A & F University, Hangzhou, China
- College of Advanced Agricultural Sciences, Zhejiang A & F University, Hangzhou, China
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Struik PC, Driever SM. Intriguing correlations between leaf architecture and intrinsic water-use efficiency enable selective breeding to mitigate climate challenges. PLANT, CELL & ENVIRONMENT 2022; 45:1607-1611. [PMID: 35274305 PMCID: PMC9313581 DOI: 10.1111/pce.14305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 02/25/2022] [Accepted: 03/03/2022] [Indexed: 06/14/2023]
Affiliation(s)
- Paul Christiaan Struik
- Centre for Crop Systems AnalysisWageningen University and ResearchWageningenThe Netherlands
| | - Steven Michiel Driever
- Centre for Crop Systems AnalysisWageningen University and ResearchWageningenThe Netherlands
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Pan L, George-Jaeggli B, Borrell A, Jordan D, Koller F, Al-Salman Y, Ghannoum O, Cano FJ. Coordination of stomata and vein patterns with leaf width underpins water-use efficiency in a C 4 crop. PLANT, CELL & ENVIRONMENT 2022; 45:1612-1630. [PMID: 34773276 DOI: 10.1111/pce.14225] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 10/08/2021] [Accepted: 11/05/2021] [Indexed: 06/13/2023]
Abstract
Despite its importance for crop water use and productivity, especially in drought-affected environments, the underlying mechanisms of variation in intrinsic water-use efficiency (iWUE = net photosynthesis/stomatal conductance for water vapour, gsw ) are not well understood, especially in C4 plants. Recently, we discovered that leaf width (LW) correlated negatively with iWUE and positively with gsw across several C4 grasses. Here, we confirmed these relationships within 48 field-grown genotypes differing in LW in Sorghum bicolor, a C4 crop adapted to dry and hot conditions. We measured leaf gas exchange and modelled leaf energy balance three times a day, alongside anatomical traits as potential predictors of iWUE. LW correlated negatively with iWUE and stomatal density, but positively with gsw , interveinal distance of longitudinal veins, and the percentage of stomatal aperture relative to maximum. Energy balance modelling showed that wider leaves needed to open their stomata more to generate a more negative leaf-to-air temperature difference, especially at midday when air temperatures exceeded 40°C. These results highlight the important role that LW plays in shaping iWUE through coordination of vein and stomatal traits and by affecting stomatal aperture. Therefore, LW could be used as a predictor of higher iWUE among sorghum genotypes.
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Affiliation(s)
- Ling Pan
- ARC Centre of Excellence for Translational Photosynthesis, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
- Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan, China
- College of Forestry, Hainan University, Haikou, Hainan, China
| | - Barbara George-Jaeggli
- ARC Centre of Excellence for Translational Photosynthesis, Australia
- Queensland Alliance for Agriculture and Food Innovation, Hermitage Research Facility, The University of Queensland, Warwick, Queensland, Australia
- Department of Agriculture and Fisheries, Agri-Science Queensland, Hermitage Research Facility, Warwick, Queensland, Australia
| | - Andrew Borrell
- ARC Centre of Excellence for Translational Photosynthesis, Australia
- Queensland Alliance for Agriculture and Food Innovation, Hermitage Research Facility, The University of Queensland, Warwick, Queensland, Australia
| | - David Jordan
- ARC Centre of Excellence for Translational Photosynthesis, Australia
- Queensland Alliance for Agriculture and Food Innovation, Hermitage Research Facility, The University of Queensland, Warwick, Queensland, Australia
| | - Fiona Koller
- ARC Centre of Excellence for Translational Photosynthesis, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Yazen Al-Salman
- ARC Centre of Excellence for Translational Photosynthesis, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Oula Ghannoum
- ARC Centre of Excellence for Translational Photosynthesis, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Francisco J Cano
- ARC Centre of Excellence for Translational Photosynthesis, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
- Centro de Investigación Forestal (CIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
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Hendriks PW, Ryan PR, Hands P, Rolland V, Gurusinghe S, Weston LA, Rebetzke GJ, Delhaize E. Selection for early shoot vigour in wheat increases root hair length but reduces epidermal cell size of roots and leaves. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:2499-2510. [PMID: 35195714 PMCID: PMC9015806 DOI: 10.1093/jxb/erac048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 02/11/2022] [Indexed: 05/22/2023]
Abstract
Six cycles of recurrent selection for early shoot vigour in wheat resulted in significant increases in leaf width and shoot biomass. Here, in replicated controlled-environment studies, the effect of early shoot vigour on root biomass, rhizosheath size, root hair length, and cell size in the roots and leaves was examined across different cycles of selection. Increased shoot vigour was associated with greater root biomass, larger rhizosheath size, and longer root hairs. Our findings demonstrate that rhizosheath size was a reliable surrogate for root hair length in this germplasm. Examination of the root epidermis revealed that the 'cell body' of the trichoblasts (hair-forming cells) and the atrichoblasts (non-hair-forming cells) decreased in size as shoot vigour increased. Therefore, in higher vigour germplasm, longer root hairs emerged from smaller trichoblasts so that total trichoblast volume (root hair plus cell body) was generally similar regardless of shoot vigour. Similarly, the sizes of the four main cell types on the leaf epidermis became progressively smaller as shoot vigour increased, which also increased stomatal density. The relationship between shoot vigour and root traits is considered, and the potential contribution of below-ground root traits to performance and competitiveness of high vigour germplasm is discussed.
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Affiliation(s)
- Pieter-Willem Hendriks
- CSIRO, Agriculture and Food, Canberra, ACT, 2601, Australia
- Charles Sturt University, School of Agriculture, Environment and Veterinary Sciences, Wagga-Wagga, 14 NSW, 2650, Australia
- Graham Centre for Agricultural Innovation, Wagga Wagga, NSW, 2678, Australia
- Correspondence:
| | - Peter R Ryan
- CSIRO, Agriculture and Food, Canberra, ACT, 2601, Australia
| | - Philip Hands
- CSIRO, Agriculture and Food, Canberra, ACT, 2601, Australia
| | - Vivien Rolland
- CSIRO, Agriculture and Food, Canberra, ACT, 2601, Australia
| | - Saliya Gurusinghe
- Graham Centre for Agricultural Innovation, Wagga Wagga, NSW, 2678, Australia
| | - Leslie A Weston
- Graham Centre for Agricultural Innovation, Wagga Wagga, NSW, 2678, Australia
| | | | - Emmanuel Delhaize
- Australian Plant Phenomics Facility, Australian National University Node, 134 Linnaeus Way, Acton ACT 2601, Australia
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Huang G, Shu Y, Peng S, Li Y. Leaf photosynthesis is positively correlated with xylem and phloem areas in leaf veins in rice (Oryza sativa) plants. ANNALS OF BOTANY 2022; 129:619-631. [PMID: 35143609 PMCID: PMC9007091 DOI: 10.1093/aob/mcac020] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 02/09/2022] [Indexed: 05/23/2023]
Abstract
BACKGROUND AND AIMS Leaf structure is an important determinant of leaf photosynthesis; however, the impacts of leaf structural traits on gas exchange parameters are still not fully understood. In the present study, 11 rice genotypes were grown in pots to investigate the influence of leaf structural traits on leaf photosynthesis and hydraulic conductance (Kleaf). METHODS In this study, leaf photosynthetic rate (A), stomatal conductance (gs), mesophyll conductance and Kleaf were measured. In addition, leaf structural traits including leaf thickness (LT), leaf mass per area and leaf xylem and phloem sizes were also measured to investigate their impacts on rice photosynthesis. KEY RESULTS We found that the total area of xylem conduits per major vein (Xmajor), leaf phloem area per minor vein (Pminor) and LT were positively correlated with Kleaf, gs and A. The path analysis suggested that, however, only Pminor had a direct impact on A; Xmajor had an indirect impact on A via gs and Pminor, while LT did not show any direct or indirect impact on A. CONCLUSION This study highlighted the importance of manipulations in Xmajor and Pminor, two previously overlooked leaf traits, to improve leaf photosynthesis in rice plants.
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Affiliation(s)
- Guanjun Huang
- National Key Laboratory of Crop Genetic Improvement, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Yu Shu
- National Key Laboratory of Crop Genetic Improvement, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Shaobing Peng
- National Key Laboratory of Crop Genetic Improvement, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Yong Li
- National Key Laboratory of Crop Genetic Improvement, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
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13
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Lo SF, Chatterjee J, Biswal AK, Liu IL, Chang YP, Chen PJ, Wanchana S, Elmido-Mabilangan A, Nepomuceno RA, Bandyopadhyay A, Hsing YI, Quick WP. Closer vein spacing by ectopic expression of nucleotide-binding and leucine-rich repeat proteins in rice leaves. PLANT CELL REPORTS 2022; 41:319-335. [PMID: 34837515 PMCID: PMC8850240 DOI: 10.1007/s00299-021-02810-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 11/08/2021] [Indexed: 06/13/2023]
Abstract
Elevated expression of nucleotide-binding and leucine-rich repeat proteins led to closer vein spacing and higher vein density in rice leaves. To feed the growing global population and mitigate the negative effects of climate change, there is a need to improve the photosynthetic capacity and efficiency of major crops such as rice to enhance grain yield potential. Alterations in internal leaf morphology and cellular architecture are needed to underpin some of these improvements. One of the targets is to generate a "Kranz-like" anatomy in leaves that includes decreased interveinal spacing close to that in C4 plant species. As C4 photosynthesis has evolved from C3 photosynthesis independently in multiple lineages, the genes required to facilitate C4 may already be present in the rice genome. The Taiwan Rice Insertional Mutants (TRIM) population offers the advantage of gain-of-function phenotype trapping, which accelerates the identification of rice gene function. In the present study, we screened the TRIM population to determine the extent to which genetic plasticity can alter vein density (VD) in rice. Close vein spacing mutant 1 (CVS1), identified from a VD screening of approximately 17,000 TRIM lines, conferred heritable high leaf VD. Increased vein number in CVS1 was confirmed to be associated with activated expression of two nucleotide-binding and leucine-rich repeat (NB-LRR) proteins. Overexpression of the two NB-LRR genes individually in rice recapitulates the high VD phenotype, due mainly to reduced interveinal mesophyll cell (M cell) number, length, bulliform cell size and thus interveinal distance. Our studies demonstrate that the trait of high VD in rice can be achieved by elevated expression of NB-LRR proteins limited to no yield penalty.
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Affiliation(s)
- Shuen-Fang Lo
- Biotechnology Center, National Chung Hsing University, Taichung, 402, Taiwan, ROC.
| | - Jolly Chatterjee
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | - Akshaya K Biswal
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
- Genetic Resources Program, International Maize and Wheat Improvement Center (CIMMYT), Carretera México-Veracruz km. 45, El Batán, Texcoco, CP 56237, México
| | - I-Lun Liu
- Biotechnology Center, National Chung Hsing University, Taichung, 402, Taiwan, ROC
| | - Yu-Pei Chang
- Biotechnology Center, National Chung Hsing University, Taichung, 402, Taiwan, ROC
| | - Pei-Jing Chen
- Biotechnology Center, National Chung Hsing University, Taichung, 402, Taiwan, ROC
| | - Samart Wanchana
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines
| | | | - Robert A Nepomuceno
- National Institute of Molecular Biology and Biotechnology, University of the Philippines (BIOTECH-UPLB), Los Baños, 4031, Philippines
| | | | - Yue-Ie Hsing
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 115, Taiwan, ROC
| | - William Paul Quick
- C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines.
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK.
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14
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Marzban M, Farahani F, Atyabi SM, Noormohammadi Z. Induced genetic and chemical changes in medicinally important plant Catharanthus roseus (L.) G. Don: cold plasma and phytohormones. Mol Biol Rep 2021; 49:31-38. [PMID: 34773551 DOI: 10.1007/s11033-021-06789-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 09/17/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND Catharanthus roseus (L.) G. Donis a medicinal plant species belonging to the Apocynaceae family, which produces vinblastine and vincristine along with 100 other monoterpenoid indole alkaloids. The process of biosynthesis of C. roseus alkaloids is complex, in which many genes, enzymes, and regulators are involved. Induced mutations may be considered as a potential source for producing a higher amount of vinblastine and vincristine in this plant species. Therefore, the objective of the present study was to examine the effects of different treatments utilized on the induced genetic changes in C. roseus plants and enzyme activities. METHODS AND RESULTS Spermine, jasmonic acid, methyjasmonate, putrescine, and cold plasma treatments were used for seed treatments. Different molecular markers, namely inter simple sequence repeat, inter retrotransposon amplified polymorphism, and retrotransposon microsatellite amplified polymorphism were employed to reveal the induced genetic changes. Antioxidant enzyme activities were also studied. The treated plants showed genetic variability and a significant increase in antioxidant enzyme activity compared to the control plants. The putrescine treatment resulted in the highest level of activity in superoxidase. A significant positive correlation occurred between the molecular markers data and antioxidant enzyme activities in treated plants. CONCLUSION Our data revealed that the different phytohormones and cold plasma treatments could induce both genetic and chemical content changes in C. roseus plants.
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Affiliation(s)
- Maryam Marzban
- Biology Department, Science and Research Branch, Islamic Azad University, Tehran, Islamic Republic of Iran
| | - Farah Farahani
- Department of Microbiology, Qom Branch, Islamic Azad University, Qom, Islamic Republic of Iran
| | - Seyed Mohammad Atyabi
- Department of Nano Biotechnology, Pasteur Institute of Iran, Tehran, Islamic Republic of Iran.
| | - Zahra Noormohammadi
- Biology Department, Science and Research Branch, Islamic Azad University, Tehran, Islamic Republic of Iran.
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15
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Mathan J, Singh A, Jathar V, Ranjan A. High photosynthesis rate in two wild rice species is driven by leaf anatomy mediating high Rubisco activity and electron transport rate. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:7119-7135. [PMID: 34185840 DOI: 10.1093/jxb/erab313] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/26/2021] [Indexed: 06/13/2023]
Abstract
The importance of increasing photosynthetic efficiency for sustainable crop yield increases to feed the growing world population is well recognized. The natural genetic variation in leaf photosynthesis in crop plants is largely unexploited for increasing yield potential. The genus Oryza, including cultivated rice and wild relatives, offers tremendous genetic variability to explore photosynthetic differences and underlying biochemical, photochemical, and developmental traits. We quantified leaf photosynthesis and related physiological parameters for six cultivated and three wild rice genotypes, and identified photosynthetically efficient wild rice accessions. Fitting A/Ci curves and biochemical analyses showed that leaf photosynthesis in cultivated rice varieties IR 64 and Nipponbare was limited due to leaf nitrogen content, Rubisco activity, and electron transport rate compared with photosynthetically efficient wild rice accessions Oryza australiensis and Oryza latifolia. The selected wild rice accessions with high leaf photosynthesis per unit area had anatomical features such as larger mesophyll cells with more chloroplasts, fewer mesophyll cells between two adjacent veins, and higher mesophyll cell and chloroplast surface area exposed to intercellular space. Our results show the existence of desirable variations in Rubisco activity, electron transport rate, and leaf anatomical features that could be targeted for increasing the photosynthetic efficiency of cultivated rice varieties.
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Affiliation(s)
- Jyotirmaya Mathan
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Anuradha Singh
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Vikram Jathar
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Aashish Ranjan
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
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16
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Robil JM, Gao K, Neighbors CM, Boeding M, Carland FM, Bunyak F, McSteen P. grasviq: an image analysis framework for automatically quantifying vein number and morphology in grass leaves. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:629-648. [PMID: 33914380 DOI: 10.1111/tpj.15299] [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: 01/22/2021] [Revised: 04/16/2021] [Accepted: 04/21/2021] [Indexed: 06/12/2023]
Abstract
Beyond facilitating transport and providing mechanical support to the leaf, veins have important roles in the performance and productivity of plants and the ecosystem. In recent decades, computational image analysis has accelerated the extraction and quantification of vein traits, benefiting fields of research from agriculture to climatology. However, most of the existing leaf vein image analysis programs have been developed for the reticulate venation found in dicots. Despite the agroeconomic importance of cereal grass crops, like Oryza sativa (rice) and Zea mays (maize), a dedicated image analysis program for the parallel venation found in monocots has yet to be developed. To address the need for an image-based vein phenotyping tool for model and agronomic grass species, we developed the grass vein image quantification (grasviq) framework. Designed specifically for parallel venation, this framework automatically segments and quantifies vein patterns from images of cleared leaf pieces using classical computer vision techniques. Using image data sets from maize inbred lines and auxin biosynthesis and transport mutants in maize, we demonstrate the utility of grasviq for quantifying important vein traits, including vein density, vein width and interveinal distance. Furthermore, we show that the framework can resolve quantitative differences and identify vein patterning defects, which is advantageous for genetic experiments and mutant screens. We report that grasviq can perform high-throughput vein quantification, with precision on a par with that of manual quantification. Therefore, we envision that grasviq will be adopted for vein phenomics in maize and other grass species.
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Affiliation(s)
- Janlo M Robil
- Division of Biological Sciences, Interdisciplinary Plant Group, and Missouri Maize Center, University of Missouri, Columbia, Missouri, 65211, USA
| | - Ke Gao
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, Missouri, 65211, USA
| | - Claire M Neighbors
- Division of Biological Sciences, Interdisciplinary Plant Group, and Missouri Maize Center, University of Missouri, Columbia, Missouri, 65211, USA
| | - Michael Boeding
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, Missouri, 65211, USA
| | - Francine M Carland
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, 06520, USA
| | - Filiz Bunyak
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, Missouri, 65211, USA
| | - Paula McSteen
- Division of Biological Sciences, Interdisciplinary Plant Group, and Missouri Maize Center, University of Missouri, Columbia, Missouri, 65211, USA
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17
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OsARF11 Promotes Growth, Meristem, Seed, and Vein Formation during Rice Plant Development. Int J Mol Sci 2021; 22:ijms22084089. [PMID: 33920962 PMCID: PMC8071273 DOI: 10.3390/ijms22084089] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/06/2021] [Accepted: 04/13/2021] [Indexed: 11/17/2022] Open
Abstract
The plant hormone auxin acts as a mediator providing positional instructions in a range of developmental processes. Studies in Arabidopsis thaliana L. show that auxin acts in large part via activation of Auxin Response Factors (ARFs) that in turn regulate the expression of downstream genes. The rice (Oryza sativa L.) gene OsARF11 is of interest because of its expression in developing rice organs and its high sequence similarity with MONOPTEROS/ARF5, a gene with prominent roles in A. thaliana development. We have assessed the phenotype of homozygous insertion mutants in the OsARF11 gene and found that in relation to wildtype, osarf11 seedlings produced fewer and shorter roots as well as shorter and less wide leaves. Leaves developed fewer veins and larger areoles. Mature osarf11 plants had a reduced root system, fewer branches per panicle, fewer grains per panicle and fewer filled seeds. Mutants had a reduced sensitivity to auxin-mediated callus formation and inhibition of root elongation, and phenylboronic acid (PBA)-mediated inhibition of vein formation. Taken together, our results implicate OsARF11 in auxin-mediated growth of multiple organs and leaf veins. OsARF11 also appears to play a central role in the formation of lateral root, panicle branch, and grain meristems.
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18
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Developmental and biophysical determinants of grass leaf size worldwide. Nature 2021; 592:242-247. [PMID: 33762735 DOI: 10.1038/s41586-021-03370-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 02/18/2021] [Indexed: 02/01/2023]
Abstract
One of the most notable ecological trends-described more than 2,300 years ago by Theophrastus-is the association of small leaves with dry and cold climates, which has recently been recognized for eudicotyledonous plants at a global scale1-3. For eudicotyledons, this pattern has been attributed to the fact that small leaves have a thinner boundary layer that helps to avoid extreme leaf temperatures4 and their leaf development results in vein traits that improve water transport under cold or dry climates5,6. However, the global distribution of leaf size and its adaptive basis have not been tested in the grasses, which represent a diverse lineage that is distinct in leaf morphology and that contributes 33% of terrestrial primary productivity (including the bulk of crop production)7. Here we demonstrate that grasses have shorter and narrower leaves under colder and drier climates worldwide. We show that small grass leaves have thermal advantages and vein development that contrast with those of eudicotyledons, but that also explain the abundance of small leaves in cold and dry climates. The worldwide distribution of leaf size in grasses exemplifies how biophysical and developmental processes result in convergence across major lineages in adaptation to climate globally, and highlights the importance of leaf size and venation architecture for grass performance in past, present and future ecosystems.
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Liao S, Yan J, Xing H, Tu Y, Zhao H, Wang G. Genetic basis of vascular bundle variations in rice revealed by genome-wide association study. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 302:110715. [PMID: 33288021 DOI: 10.1016/j.plantsci.2020.110715] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/30/2020] [Accepted: 10/09/2020] [Indexed: 06/12/2023]
Abstract
The vascular bundles play important roles in transportation of photoassimilate, and the number, size, and capacity of vascular bundles influence the transportation efficiency. Dissecting the genetic basis may help to make better use of naturally occurring vascular bundle variations. Here, we conducted a genome-wide association study (GWAS) of the vascular bundle variations in a worldwide collection of 529 Oryza sativa accessions. A total of 42 and 93 significant association loci were identified in the neck panicle and flag leaf, respectively. The introgression lines showing extreme values of the target traits harbored at least one GWAS signal, indicating the reliability of the GWAS loci. Based on the data of near-isogenic lines and transgenic plants, Grain number, plant height, and heading date7 (Ghd7) was identified as a major locus for the natural variation of vascular bundles in the neck panicle at the heading stage. In addition, Narrow leaf1 (NAL1) was found to influence the vascular bundles in both the neck panicle and flag leaf, and the effects of the major haplotypes of NAL1 were characterized. The loci or candidate genes identified would help to improve vascular bundle system in rice breeding.
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Affiliation(s)
- Shiyu Liao
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China
| | - Ju Yan
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China
| | - Hongkun Xing
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China
| | - Yuan Tu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China
| | - Hu Zhao
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China
| | - Gongwei Wang
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China.
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20
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Zhu J, Yao J, Yu Q, He W, Xu C, Qin G, Zhu Q, Fan D, Zhu H. A Fast and Automatic Method for Leaf Vein Network Extraction and Vein Density Measurement Based on Object-Oriented Classification. FRONTIERS IN PLANT SCIENCE 2020; 11:499. [PMID: 32431721 PMCID: PMC7214732 DOI: 10.3389/fpls.2020.00499] [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: 04/26/2019] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
Rapidly determining leaf vein network patterns and vein densities is biologically important and technically challenging. Current methods, however, are limited to vein contour extraction. Further image processing is difficult, and some leaf vein traits of interest therefore cannot be quantified. In this study, we proposed a novel method for the fast and accurate determination of leaf vein network patterns and vein density. Nine tree species with different leaf characteristics and vein types were applied to verify this method. To overcome the image processing difficulties at the microscopic scale, we adopted the remote object-oriented classification method applied comprehensively in the field of remote sensing research. The key to this approach is to determine the universally applicable leaf vein extraction threshold values (scale parameter, shape parameter, compactness parameter, brightness feature, spectral feature and geometric feature). Based on our analysis, the following recommended threshold values were determined: the scale parameter was 250, the shape parameter was 0.7, the compactness parameter was 0.3, the brightness feature value was 230∼280, the spectral feature value was 180∼230, and the geometric feature value was less than 2. With the optimal extraction parameters applied, the extraction precision was above 96.40% on average for the nine species studied. The leaf vein density calculation rate increased by more than 87.3% compared to that of the traditional methods. The results showed that this method is accurate, fast, flexible and complementary to existing technologies. It is an effective tool for the fast extraction of vein networks and the exploration of leaf vein characteristics, particularly for large-scale studies in plant vein physiology.
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Affiliation(s)
- Jiyou Zhu
- Key Laboratory for Silviculture and Conservation of Ministry of Education, Key Laboratory for Silviculture and Forest Ecosystem of State Forestry Administration, Research Center for Urban Forestry, Beijing Forestry University, Beijing, China
| | - Jiangming Yao
- Forestry College, Guangxi University, Nanning, China
| | - Qiang Yu
- Key Laboratory for Silviculture and Conservation of Ministry of Education, Key Laboratory for Silviculture and Forest Ecosystem of State Forestry Administration, Research Center for Urban Forestry, Beijing Forestry University, Beijing, China
| | - Weijun He
- Forestry College, Guangxi University, Nanning, China
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Chengyang Xu
- Key Laboratory for Silviculture and Conservation of Ministry of Education, Key Laboratory for Silviculture and Forest Ecosystem of State Forestry Administration, Research Center for Urban Forestry, Beijing Forestry University, Beijing, China
| | - Guoming Qin
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Qiuyu Zhu
- Inspection Department of Guangxi Medical College, Nanning, China
| | - Dayong Fan
- Key Laboratory for Silviculture and Conservation of Ministry of Education, Key Laboratory for Silviculture and Forest Ecosystem of State Forestry Administration, Research Center for Urban Forestry, Beijing Forestry University, Beijing, China
| | - Hua Zhu
- Inspection Department of Guangxi Medical College, Nanning, China
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21
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Viana VE, Pegoraro C, Busanello C, Costa de Oliveira A. Mutagenesis in Rice: The Basis for Breeding a New Super Plant. FRONTIERS IN PLANT SCIENCE 2019; 10:1326. [PMID: 31781133 PMCID: PMC6857675 DOI: 10.3389/fpls.2019.01326] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 09/24/2019] [Indexed: 05/28/2023]
Abstract
The high selection pressure applied in rice breeding since its domestication thousands of years ago has caused a narrowing in its genetic variability. Obtaining new rice cultivars therefore becomes a major challenge for breeders and developing strategies to increase the genetic variability has demanded the attention of several research groups. Understanding mutations and their applications have paved the way for advances in the elucidation of a genetic, physiological, and biochemical basis of rice traits. Creating variability through mutations has therefore grown to be among the most important tools to improve rice. The small genome size of rice has enabled a faster release of higher quality sequence drafts as compared to other crops. The move from structural to functional genomics is possible due to an array of mutant databases, highlighting mutagenesis as an important player in this progress. Furthermore, due to the synteny among the Poaceae, other grasses can also benefit from these findings. Successful gene modifications have been obtained by random and targeted mutations. Furthermore, following mutation induction pathways, techniques have been applied to identify mutations and the molecular control of DNA damage repair mechanisms in the rice genome. This review highlights findings in generating rice genome resources showing strategies applied for variability increasing, detection and genetic mechanisms of DNA damage repair.
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Affiliation(s)
| | | | | | - Antonio Costa de Oliveira
- Centro de Genômica e Fitomelhoramento, Faculdade de Agronomia Eliseu Maciel, Departamento de Fitotecnia, Universidade Federal de Pelotas, Campus Capão do Leão, Rio Grande do Sul, Brazil
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22
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Dehigaspitiya P, Milham P, Ash GJ, Arun-Chinnappa K, Gamage D, Martin A, Nagasaka S, Seneweera S. Exploring natural variation of photosynthesis in a site-specific manner: evolution, progress, and prospects. PLANTA 2019; 250:1033-1050. [PMID: 31254100 DOI: 10.1007/s00425-019-03223-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 06/20/2019] [Indexed: 06/09/2023]
Abstract
Site-specific changes of photosynthesis, a relatively new concept, can be used to improve the productivity of critical food crops to mitigate the foreseen food crisis. Global food security is threatened by an increasing population and the effects of climate change. Large yield improvements were achieved in major cereal crops between the 1950s and 1980s through the Green Revolution. However, we are currently experiencing a significant decline in yield progress. Of the many approaches to improved cereal yields, exploitation of the mode of photosynthesis has been intensely studied. Even though the C4 pathway is considered the most efficient, mainly because of the carbon concentrating mechanisms around the enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase, which minimize photorespiration, much is still unknown about the specific gene regulation of this mode of photosynthesis. Most of the critical cereal crops, including wheat and rice, are categorized as C3 plants based on the photosynthesis of major photosynthetic organs. However, recent findings raise the possibility of different modes of photosynthesis occurring at different sites in the same plant and/or in plants grown in different habitats. That is, it seems possible that efficient photosynthetic traits may be expressed in specific organs, even though the major photosynthetic pathway is C3. Knowledge of site-specific differences in photosynthesis, coupled with site-specific regulation of gene expression, may therefore hold a potential to enhance the yields of economically important C3 crops.
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Affiliation(s)
| | - Paul Milham
- Hawkesbury Institute for the Environment, Western Sydney University, LB 1797, Penrith, NSW, 2753, Australia
| | - Gavin J Ash
- Centre for Crop Health, University of Southern Queensland, Toowoomba, QLD, 4350, Australia
| | - Kiruba Arun-Chinnappa
- Centre for Crop Health, University of Southern Queensland, Toowoomba, QLD, 4350, Australia
| | - Dananjali Gamage
- Centre for Crop Health, University of Southern Queensland, Toowoomba, QLD, 4350, Australia
| | - Anke Martin
- Centre for Crop Health, University of Southern Queensland, Toowoomba, QLD, 4350, Australia
| | - Seiji Nagasaka
- Centre for Crop Health, University of Southern Queensland, Toowoomba, QLD, 4350, Australia
| | - Saman Seneweera
- Centre for Crop Health, University of Southern Queensland, Toowoomba, QLD, 4350, Australia.
- National Institute of Fundamental Studies, Hanthana Road, Kandy, 20000, Central, Sri Lanka.
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Flood PJ. Using natural variation to understand the evolutionary pressures on plant photosynthesis. CURRENT OPINION IN PLANT BIOLOGY 2019; 49:68-73. [PMID: 31284076 DOI: 10.1016/j.pbi.2019.06.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 05/23/2019] [Accepted: 06/03/2019] [Indexed: 06/09/2023]
Abstract
Photosynthesis is the gateway of the Sun's energy into the biosphere and the source of the ozone layer; thus it is both provider and protector of life as we know it. Despite its pivotal role we know surprisingly little about the genetic basis of variation in photosynthesis and the selective pressures giving rise to or maintaining this variation. In this review, I will briefly summarise our current knowledge of intraspecific and interspecific variation in photosynthesis to understand the main selective constraints on photosynthesis and what this means for the future of nature and agriculture in a changing world.
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Affiliation(s)
- Pádraic J Flood
- Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany.
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24
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Faralli M, Cockram J, Ober E, Wall S, Galle A, Van Rie J, Raines C, Lawson T. Genotypic, Developmental and Environmental Effects on the Rapidity of gs in Wheat: Impacts on Carbon Gain and Water-Use Efficiency. FRONTIERS IN PLANT SCIENCE 2019; 10:492. [PMID: 31057590 PMCID: PMC6479173 DOI: 10.3389/fpls.2019.00492] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 04/01/2019] [Indexed: 05/20/2023]
Abstract
Stomata are the primary gatekeepers for CO2 uptake for photosynthesis and water loss via transpiration and therefore play a central role in crop performance. Although stomatal conductance (gs ) and assimilation rate (A) are often highly correlated, studies have demonstrated an uncoupling between A and gs that can result in sub-optimal physiological processes in dynamic light environments. Wheat (Triticum aestivum L.) is exposed to changes in irradiance due to leaf self-shading, moving clouds and shifting sun angle to which both A and gs respond. However, stomatal responses are generally an order of magnitude slower than photosynthetic responses, leading to non-synchronized A and gs responses that impact CO2 uptake and water use efficiency ( iWUE). Here we phenotyped a panel of eight wheat cultivars (estimated to capture 80% of the single nucleotide polymorphism variation in North-West European bread wheat) for differences in the speed of stomatal responses (to changes in light intensity) and photosynthetic performance at different stages of development. The impact of water stress and elevated [CO2] on stomatal kinetics was also examined in a selected cultivar. Significant genotypic variation was reported for the time constant for stomatal opening (Ki, P = 0.038) and the time to reach 95% steady state A (P = 0.045). Slow gs opening responses limited A by ∼10% and slow closure reduced iWUE, with these impacts found to be greatest in cultivars Soissons, Alchemy and Xi19. A decrease in stomatal rapidity (and thus an increase in the limitation of photosynthesis) (P < 0.001) was found during the post-anthesis stage compared to the early booting stage. Reduced water availability triggered stomatal closure and asymmetric stomatal opening and closing responses, while elevated atmospheric [CO2] conditions reduced the time for stomatal opening during a low to high light transition, thus suggesting a major environmental effect on dynamic stomatal kinetics. We discuss these findings in terms of exploiting various traits to develop ideotypes for specific environments, and suggest that intraspecific variation in the rapidity of stomatal responses could provide a potential unexploited breeding target to optimize the physiological responses of wheat to dynamic field conditions.
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Affiliation(s)
- Michele Faralli
- School of Biological Sciences, University of Essex, Colchester, United Kingdom
| | - James Cockram
- The John Bingham Laboratory, NIAB, Cambridge, United Kingdom
| | - Eric Ober
- The John Bingham Laboratory, NIAB, Cambridge, United Kingdom
| | - Shellie Wall
- School of Biological Sciences, University of Essex, Colchester, United Kingdom
| | | | | | - Christine Raines
- School of Biological Sciences, University of Essex, Colchester, United Kingdom
| | - Tracy Lawson
- School of Biological Sciences, University of Essex, Colchester, United Kingdom
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25
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Éva C, Oszvald M, Tamás L. Current and possible approaches for improving photosynthetic efficiency. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 280:433-440. [PMID: 30824023 DOI: 10.1016/j.plantsci.2018.11.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 10/09/2018] [Accepted: 11/19/2018] [Indexed: 06/09/2023]
Abstract
One of the most important tasks laying ahead today's biotechnology is to improve crop productivity with the aim of meeting increased food and energy demands of humankind. Plant productivity depends on many genetic factors, including life cycle, harvest index, stress tolerance and photosynthetic activity. Many approaches were already tested or suggested to improve either. Limitations of photosynthesis have also been uncovered and efforts been taken to increase its efficiency. Examples include decreasing photosynthetic antennae size, increasing the photosynthetically available light spectrum, countering oxygenase activity of Rubisco by implementing C4 photosynthesis to C3 plants and altering source to sink transport of metabolites. A natural and effective photosynthetic adaptation, the sugar alcohol metabolism got however remarkably little attention in the last years, despite being comparably efficient as C4, and can be considered easier to introduce to new species. We also propose root to shoot carbon-dioxide transport as a means to improve photosynthetic performance and drought tolerance at the same time. Different suggestions and successful examples are covered here for improving plant photosynthesis as well as novel perspectives are presented for future research.
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Affiliation(s)
- Csaba Éva
- Applied Genomics Department, Agricultural Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Martonvásár 2462, Hungary.
| | - Mária Oszvald
- Plant Biology and Crop Science, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK
| | - László Tamás
- Department of Plant Physiology and Molecular Plant Biology, Eötvös Loránd University, Budapest 1117, Hungary
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26
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Ren T, Weraduwage SM, Sharkey TD. Prospects for enhancing leaf photosynthetic capacity by manipulating mesophyll cell morphology. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:1153-1165. [PMID: 30590670 DOI: 10.1093/jxb/ery448] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 12/25/2018] [Indexed: 06/09/2023]
Abstract
Leaves are beautifully specialized organs designed to maximize the use of light and CO2 for photosynthesis. Engineering leaf anatomy therefore holds great potential to enhance photosynthetic capacity. Here we review the effect of the dominant leaf anatomical traits on leaf photosynthesis and confirm that a high chloroplast surface area exposed to intercellular airspace per unit leaf area (Sc) is critical for efficient photosynthesis. The possibility of improving Sc through appropriately increasing mesophyll cell density is further analyzed. The potential influences of modifying mesophyll cell morphology on CO2 diffusion, light distribution within the leaf, and other physiological processes are also discussed. Some potential target genes regulating leaf mesophyll cell proliferation and expansion are explored. Indeed, more comprehensive research is needed to understand how manipulating mesophyll cell morphology through editing the potential target genes impacts leaf photosynthetic capacity and related physiological processes. This will pinpoint the targets for engineering leaf anatomy to maximize photosynthetic capacity.
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Affiliation(s)
- Tao Ren
- College of Resources and Environment, Huazhong Agricultural University, China
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA
| | - Sarathi M Weraduwage
- Department of Energy Plant Research Laboratory and Plant Resiience Institute, Michigan State University, East Lansing, USA
| | - Thomas D Sharkey
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA
- Department of Energy Plant Research Laboratory and Plant Resiience Institute, Michigan State University, East Lansing, USA
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27
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Sedelnikova OV, Hughes TE, Langdale JA. Understanding the Genetic Basis of C 4 Kranz Anatomy with a View to Engineering C 3 Crops. Annu Rev Genet 2018; 52:249-270. [PMID: 30208293 DOI: 10.1146/annurev-genet-120417-031217] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
One of the most remarkable examples of convergent evolution is the transition from C3 to C4 photosynthesis, an event that occurred on over 60 independent occasions. The evolution of C4 is particularly noteworthy because of the complexity of the developmental and metabolic changes that took place. In most cases, compartmentalized metabolic reactions were facilitated by the development of a distinct leaf anatomy known as Kranz. C4 Kranz anatomy differs from ancestral C3 anatomy with respect to vein spacing patterns across the leaf, cell-type specification around veins, and cell-specific organelle function. Here we review our current understanding of how Kranz anatomy evolved and how it develops, with a focus on studies that are dissecting the underlying genetic mechanisms. This research field has gained prominence in recent years because understanding the genetic regulation of Kranz may enable the C3-to-C4 transition to be engineered, an endeavor that would significantly enhance crop productivity.
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Affiliation(s)
- Olga V Sedelnikova
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom; , ,
| | - Thomas E Hughes
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom; , ,
| | - Jane A Langdale
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom; , ,
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28
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Stewart JJ, Polutchko SK, Demmig-Adams B, Adams WW. Arabidopsis thaliana Ei-5: Minor Vein Architecture Adjustment Compensates for Low Vein Density in Support of Photosynthesis. FRONTIERS IN PLANT SCIENCE 2018; 9:693. [PMID: 29910820 DOI: 10.3389/fpls.2018.00693/bibtex] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 05/07/2018] [Indexed: 05/21/2023]
Abstract
An Arabidopsis thaliana accession with naturally low vein density, Eifel-5 (Ei-5), was compared to Columbia-0 (Col-0) with respect to rosette growth, foliar vein architecture, photosynthesis, and transpiration. In addition to having to a lower vein density, Ei-5 grew more slowly, with significantly lower rates of rosette expansion, but had similar capacities for photosynthetic oxygen evolution on a leaf area basis compared to Col-0. The individual foliar minor veins were larger in Ei-5, with a greater number of vascular cells per vein, compared to Col-0. This compensation for low vein density resulted in similar values for the product of vein density × phloem cell number per minor vein in Ei-5 and Col-0, which suggests a similar capacity for foliar sugar export to support similar photosynthetic capacities per unit leaf area. In contrast, the product of vein density × xylem cell number per minor vein was significantly greater in Ei-5 compared to Col-0, and was associated not only with a higher ratio of water-transporting tracheary elements versus sugar-transporting sieve elements but also significantly higher foliar transpiration rates per leaf area in Ei-5. In contrast, previous studies in other systems had reported higher ratios of tracheary to sieve elements and higher transpiration rate to be associated with higher - rather than lower - vein densities. The Ei-5 accession thus further underscores the plasticity of the foliar vasculature by illustrating an example where a higher ratio of tracheary to sieve elements is associated with a lower vein density. Establishment of the Ei-5 accession, with a low vein density but an apparent overcapacity for water flux through the foliar xylem network, may have been facilitated by a higher level of precipitation in its habitat of origin compared to that of the Col-0 accession.
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Affiliation(s)
- Jared J Stewart
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO, United States
| | - Stephanie K Polutchko
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO, United States
| | - Barbara Demmig-Adams
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO, United States
| | - William W Adams
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO, United States
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29
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Stewart JJ, Polutchko SK, Demmig-Adams B, Adams WW. Arabidopsis thaliana Ei-5: Minor Vein Architecture Adjustment Compensates for Low Vein Density in Support of Photosynthesis. FRONTIERS IN PLANT SCIENCE 2018; 9:693. [PMID: 29910820 PMCID: PMC5992485 DOI: 10.3389/fpls.2018.00693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 05/07/2018] [Indexed: 05/05/2023]
Abstract
An Arabidopsis thaliana accession with naturally low vein density, Eifel-5 (Ei-5), was compared to Columbia-0 (Col-0) with respect to rosette growth, foliar vein architecture, photosynthesis, and transpiration. In addition to having to a lower vein density, Ei-5 grew more slowly, with significantly lower rates of rosette expansion, but had similar capacities for photosynthetic oxygen evolution on a leaf area basis compared to Col-0. The individual foliar minor veins were larger in Ei-5, with a greater number of vascular cells per vein, compared to Col-0. This compensation for low vein density resulted in similar values for the product of vein density × phloem cell number per minor vein in Ei-5 and Col-0, which suggests a similar capacity for foliar sugar export to support similar photosynthetic capacities per unit leaf area. In contrast, the product of vein density × xylem cell number per minor vein was significantly greater in Ei-5 compared to Col-0, and was associated not only with a higher ratio of water-transporting tracheary elements versus sugar-transporting sieve elements but also significantly higher foliar transpiration rates per leaf area in Ei-5. In contrast, previous studies in other systems had reported higher ratios of tracheary to sieve elements and higher transpiration rate to be associated with higher - rather than lower - vein densities. The Ei-5 accession thus further underscores the plasticity of the foliar vasculature by illustrating an example where a higher ratio of tracheary to sieve elements is associated with a lower vein density. Establishment of the Ei-5 accession, with a low vein density but an apparent overcapacity for water flux through the foliar xylem network, may have been facilitated by a higher level of precipitation in its habitat of origin compared to that of the Col-0 accession.
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