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Chandler JO, Wilhelmsson PKI, Fernandez-Pozo N, Graeber K, Arshad W, Pérez M, Steinbrecher T, Ullrich KK, Nguyen TP, Mérai Z, Mummenhoff K, Theißen G, Strnad M, Scheid OM, Schranz ME, Petřík I, Tarkowská D, Novák O, Rensing SA, Leubner-Metzger G. The dimorphic diaspore model Aethionema arabicum (Brassicaceae): Distinct molecular and morphological control of responses to parental and germination temperatures. THE PLANT CELL 2024; 36:2465-2490. [PMID: 38513609 PMCID: PMC11218780 DOI: 10.1093/plcell/koae085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 02/21/2024] [Accepted: 02/23/2024] [Indexed: 03/23/2024]
Abstract
Plants in habitats with unpredictable conditions often have diversified bet-hedging strategies that ensure fitness over a wider range of variable environmental factors. A striking example is the diaspore (seed and fruit) heteromorphism that evolved to maximize species survival in Aethionema arabicum (Brassicaceae) in which external and endogenous triggers allow the production of two distinct diaspores on the same plant. Using this dimorphic diaspore model, we identified contrasting molecular, biophysical, and ecophysiological mechanisms in the germination responses to different temperatures of the mucilaginous seeds (M+ seed morphs), the dispersed indehiscent fruits (IND fruit morphs), and the bare non-mucilaginous M- seeds obtained by pericarp (fruit coat) removal from IND fruits. Large-scale comparative transcriptome and hormone analyses of M+ seeds, IND fruits, and M- seeds provided comprehensive datasets for their distinct thermal responses. Morph-specific differences in co-expressed gene modules in seeds, as well as in seed and pericarp hormone contents, identified a role of the IND pericarp in imposing coat dormancy by generating hypoxia affecting abscisic acid (ABA) sensitivity. This involved expression of morph-specific transcription factors, hypoxia response, and cell wall remodeling genes, as well as altered ABA metabolism, transport, and signaling. Parental temperature affected ABA contents and ABA-related gene expression and altered IND pericarp biomechanical properties. Elucidating the molecular framework underlying the diaspore heteromorphism can provide insight into developmental responses to globally changing temperatures.
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Affiliation(s)
- Jake O Chandler
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Per K I Wilhelmsson
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg 35043, Germany
| | - Noe Fernandez-Pozo
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg 35043, Germany
- Institute for Mediterranean and Subtropical Horticulture “La Mayora” (IHSM-CSIC-UMA), Málaga 29010, Spain
| | - Kai Graeber
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Waheed Arshad
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Marta Pérez
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Tina Steinbrecher
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Kristian K Ullrich
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg 35043, Germany
| | - Thu-Phuong Nguyen
- Biosystematics Group, Wageningen University, PB Wageningen 6708, The Netherlands
| | - Zsuzsanna Mérai
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Klaus Mummenhoff
- Department of Biology, Botany, University of Osnabrück, Osnabrück 49076, Germany
| | - Günter Theißen
- Matthias Schleiden Institute/Department of Genetics, Friedrich Schiller University Jena, Jena 07743, Germany
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| | - Ortrun Mittelsten Scheid
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - M Eric Schranz
- Biosystematics Group, Wageningen University, PB Wageningen 6708, The Netherlands
| | - Ivan Petřík
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| | - Danuše Tarkowská
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| | - Stefan A Rensing
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg 35043, Germany
- Centre for Biological Signalling Studies (BIOSS), University of Freiburg, Freiburg 79104, Germany
| | - Gerhard Leubner-Metzger
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
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Kępczyński J, Dziurka M, Wójcik A. KAR 1-induced dormancy release in Avena fatua caryopses involves reduction of caryopsis sensitivity to ABA and ABA/GA s ratio in coleorhiza and radicle. PLANTA 2024; 259:126. [PMID: 38635035 PMCID: PMC11026216 DOI: 10.1007/s00425-024-04387-1] [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: 02/16/2024] [Accepted: 03/10/2024] [Indexed: 04/19/2024]
Abstract
MAIN CONCLUSION The dormancy release by KAR1 is associated with a reduction of coleorhiza and radicle sensitivity to ABA as well as with reduction the ABA/GAs ratio in the coleorhiza, by a decrease content of ABA, and in the radicle, by a decrease the ABA and an increase of the GAs contents. Both, karrikin 1 (KAR1) and gibberellin A3 (GA3), release dormancy in Avena fatua caryopses, resulting in the emergence of coleorhiza (CE) and radicle (RE). Moreover, KAR1 and GA3 stimulate CE and RE in the presence of abscisic acid (ABA), the stimulation being more effective in CE. The stimulatory effects of KAR1 and GA3 involve also the CE and RE rates. A similar effect was observed at KAR1 concentrations much lower than those of GA3. KAR1 increased the levels of bioactive GA5 and GA6 in embryos and the levels of GA1, GA5, GA3, GA6 and GA4 in radicles. The stimulatory effect of KAR1 on germination, associated with increased levels of gibberellins (GAs) and reduced levels of ABA in embryos, was counteracted by paclobutrazol (PAC), commonly regarded as a GAs biosynthesis inhibitor. Consequently, KAR1 decreased the ABA/GAs ratio, whereas PAC, used alone or in combination with KAR1, increased it. The ABA/GAs ratio was reduced by KAR1 in both coleorhiza and radicle, the effect being stronger in the latter. We present the first evidence that KAR1-induced dormancy release requires a decreased ABA/GAs ratio in coleorhiza and radicle. It is concluded that the dormancy-releasing effect of KAR1 in A. fatua caryopses includes (i) a reduction of the coleorhiza and radicle sensitivity to ABA, and (2) a reduction of the ABA/GAs ratio (i) in the coleorhiza, by decreasing the ABA content, and (ii) in the radicle, by decreasing the ABA and increasing the content GAs, particularly GA1. The results may suggest different mechanisms of dormancy release by KAR1 in monocot and dicot seeds.
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Affiliation(s)
- Jan Kępczyński
- Institute of Biology, University of Szczecin, Waska 13, 71-415, Szczecin, Poland.
| | - Michal Dziurka
- Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 20-239, Krakow, Poland
| | - Agata Wójcik
- Institute of Biology, University of Szczecin, Waska 13, 71-415, Szczecin, Poland
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Arshad W, Steinbrecher T, Wilhelmsson PK, Fernandez-Pozo N, Pérez M, Mérai Z, Rensing SA, Chandler JO, Leubner-Metzger G. Aethionema arabicum dimorphic seed trait resetting during transition to seedlings. FRONTIERS IN PLANT SCIENCE 2024; 15:1358312. [PMID: 38525145 PMCID: PMC10957558 DOI: 10.3389/fpls.2024.1358312] [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: 12/19/2023] [Accepted: 02/19/2024] [Indexed: 03/26/2024]
Abstract
The transition from germinating seeds to emerging seedlings is one of the most vulnerable plant life cycle stages. Heteromorphic diaspores (seed and fruit dispersal units) are an adaptive bet-hedging strategy to cope with spatiotemporally variable environments. While the roles and mechanisms of seedling traits have been studied in monomorphic species, which produce one type of diaspore, very little is known about seedlings in heteromorphic species. Using the dimorphic diaspore model Aethionema arabicum (Brassicaceae), we identified contrasting mechanisms in the germination responses to different temperatures of the mucilaginous seeds (M+ seed morphs), the dispersed indehiscent fruits (IND fruit morphs), and the bare non-mucilaginous M- seeds obtained from IND fruits by pericarp (fruit coat) removal. What follows the completion of germination is the pre-emergence seedling growth phase, which we investigated by comparative growth assays of early seedlings derived from the M+ seeds, bare M- seeds, and IND fruits. The dimorphic seedlings derived from M+ and M- seeds did not differ in their responses to ambient temperature and water potential. The phenotype of seedlings derived from IND fruits differed in that they had bent hypocotyls and their shoot and root growth was slower, but the biomechanical hypocotyl properties of 15-day-old seedlings did not differ between seedlings derived from germinated M+ seeds, M- seeds, or IND fruits. Comparison of the transcriptomes of the natural dimorphic diaspores, M+ seeds and IND fruits, identified 2,682 differentially expressed genes (DEGs) during late germination. During the subsequent 3 days of seedling pre-emergence growth, the number of DEGs was reduced 10-fold to 277 root DEGs and 16-fold to 164 shoot DEGs. Among the DEGs in early seedlings were hormonal regulators, in particular for auxin, ethylene, and gibberellins. Furthermore, DEGs were identified for water and ion transporters, nitrate transporter and assimilation enzymes, and cell wall remodeling protein genes encoding enzymes targeting xyloglucan and pectin. We conclude that the transcriptomes of seedlings derived from the dimorphic diaspores, M+ seeds and IND fruits, undergo transcriptional resetting during the post-germination pre-emergence growth transition phase from germinated diaspores to growing seedlings.
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Affiliation(s)
- Waheed Arshad
- Seed Biology and Technology Group, Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | - Tina Steinbrecher
- Seed Biology and Technology Group, Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | | | - Noe Fernandez-Pozo
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg, Germany
- Department Plant Breeding and Physiology, Institute for Mediterranean and Subtropical Horticulture “La Mayora” (IHSM-CSIC-UMA), Málaga, Spain
| | - Marta Pérez
- Seed Biology and Technology Group, Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | - Zsuzsanna Mérai
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna, Austria
| | - Stefan A. Rensing
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg, Germany
- Centre for Biological Signalling Studies (BIOSS), University of Freiburg, Freiburg, Germany
- Faculty of Chemistry and Pharmacy, University of Freiburg, Freiburg, Germany
| | - Jake O. Chandler
- Seed Biology and Technology Group, Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | - Gerhard Leubner-Metzger
- Seed Biology and Technology Group, Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc, Czechia
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Contreras E, Martín-Fernández L, Manaa A, Vicente-Carbajosa J, Iglesias-Fernández R. Identification of Reference Genes for Precise Expression Analysis during Germination in Chenopodium quinoa Seeds under Salt Stress. Int J Mol Sci 2023; 24:15878. [PMID: 37958860 PMCID: PMC10650251 DOI: 10.3390/ijms242115878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/24/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
Chenopodium quinoa Willd. (quinoa), a member of the Amaranthaceae family, is an allotetraploid annual plant, endemic to South America. The plant of C. quinoa presents significant ecological plasticity with exceptional adaptability to several environmental stresses, including salinity. The resilience of quinoa to several abiotic stresses, as well as its nutritional attributes, have led to significant shifts in quinoa cultivation worldwide over the past century. This work first defines germination sensu stricto in quinoa where the breakage of the pericarp and the testa is followed by endosperm rupture (ER). Transcriptomic changes in early seed germination stages lead to unstable expression levels in commonly used reference genes that are typically stable in vegetative tissues. Noteworthy, no suitable reference genes have been previously identified specifically for quinoa seed germination under salt stress conditions. This work aims to identify these genes as a prerequisite step for normalizing qPCR data. To this end, germinating seeds from UDEC2 and UDEC4 accessions, with different tolerance to salt, have been analyzed under conditions of absence (0 mM NaCl) and in the presence (250 mM NaCl) of sodium chloride. Based on the relevant literature, six candidate reference genes, Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), Monensin sensitivity1 (MON1), Polypyrimidine tract-binding protein (PTB), Actin-7 (ACT7), Ubiquitin-conjugating enzyme (UBC), and 18S ribosomal RNA (18S), were selected and assessed for stability using the RefFinder Tool encompassing the statistical algorithms geNorm, NormFinder, BestKeeper, and ΔCt in the evaluation. The data presented support the suitability of CqACT7 and CqUBC as reference genes for normalizing gene expression during seed germination under salinity stress. These recommended reference genes can be valuable tools for consistent qPCR studies on quinoa seeds.
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Affiliation(s)
- Estefanía Contreras
- Centro de Biotecnología y Genómica de Plantas-Severo Ochoa (CBGP, UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain; (E.C.); (J.V.-C.)
| | - Lucía Martín-Fernández
- Centro de Biotecnología y Genómica de Plantas-Severo Ochoa (CBGP, UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain; (E.C.); (J.V.-C.)
| | - Arafet Manaa
- Laboratory of Extremophile Plants, Centre of Biotechnology de Borj Cedria, B.P. 901, Hammam-Lif 2050, Tunisia;
| | - Jesús Vicente-Carbajosa
- Centro de Biotecnología y Genómica de Plantas-Severo Ochoa (CBGP, UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain; (E.C.); (J.V.-C.)
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas (UPM), 28040 Madrid, Spain
| | - Raquel Iglesias-Fernández
- Centro de Biotecnología y Genómica de Plantas-Severo Ochoa (CBGP, UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC), Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain; (E.C.); (J.V.-C.)
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas (UPM), 28040 Madrid, Spain
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Peirats-Llobet M, Yi C, Liew L, Berkowitz O, Narsai R, Lewsey M, Whelan J. Spatially resolved transcriptomic analysis of the germinating barley grain. Nucleic Acids Res 2023; 51:7798-7819. [PMID: 37351575 PMCID: PMC10450182 DOI: 10.1093/nar/gkad521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/26/2023] [Accepted: 06/03/2023] [Indexed: 06/24/2023] Open
Abstract
Seeds are a vital source of calories for humans and a unique stage in the life cycle of flowering plants. During seed germination, the embryo undergoes major developmental transitions to become a seedling. Studying gene expression in individual seed cell types has been challenging due to the lack of spatial information or low throughput of existing methods. To overcome these limitations, a spatial transcriptomics workflow was developed for germinating barley grain. This approach enabled high-throughput analysis of spatial gene expression, revealing specific spatial expression patterns of various functional gene categories at a sub-tissue level. This study revealed over 14 000 genes differentially regulated during the first 24 h after imbibition. Individual genes, such as the aquaporin gene family, starch degradation, cell wall modification, transport processes, ribosomal proteins and transcription factors, were found to have specific spatial expression patterns over time. Using spatial autocorrelation algorithms, we identified auxin transport genes that had increasingly focused expression within subdomains of the embryo over time, suggesting their role in establishing the embryo axis. Overall, our study provides an unprecedented spatially resolved cellular map for barley germination and identifies specific functional genomics targets to better understand cellular restricted processes during germination. The data can be viewed at https://spatial.latrobe.edu.au/.
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Affiliation(s)
- Marta Peirats-Llobet
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Changyu Yi
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Lim Chee Liew
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Oliver Berkowitz
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Reena Narsai
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Mathew G Lewsey
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - James Whelan
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
- Research Centre for Engineering Biology, College of Life Science, Zhejiang University, 718 East Haizhou Road, Haining, Jiaxing, Zhejiang 314400, China
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Kępczyński J, Wójcik A, Dziurka M. NO-mediated dormancy release of Avena fatua caryopses is associated with decrease in abscisic acid sensitivity, content and ABA/GA s ratios. PLANTA 2023; 257:101. [PMID: 37087501 PMCID: PMC10122620 DOI: 10.1007/s00425-023-04117-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 03/07/2023] [Indexed: 05/03/2023]
Abstract
MAIN CONCLUSION NO releases caryopsis dormancy in Avena fatua, the effect being dependent on the level of dormancy. The NO effect involves also the reduction of caryopsis sensitivity to ABA and to a decrease in the ABA to GAs ratio due to a decrease in ABA levels and the lack of effect on GAs levels before germination is completed. Nitric oxide (NO) from various donors (i.e. SNP, GSNO and acidified KNO2), applied to dry caryopses or during initial germination, released primary dormancy in caryopses. Dormancy in caryopses was gradually lost during dry storage (after-ripening) at 25 °C, enabling germination at 20 °C in the dark. The after-ripening effect is associated with a decrease in NO required for germination. In addition, NO decreased the sensitivity of dormant caryopses to exogenous abscisic acid (ABA) and decreased the embryos' ABA content before germination was completed. However, NO did not affect the content of bioactive gibberellins (GAs) from non-13-hydroxylation (GA4, GA7) and 13-hydroxylation (GA1, GA3, GA6.) pathways. Paclobutrazol (PAC), commonly regarded as a GAs biosynthesis inhibitor, counteracted the dormancy-releasing effect of NO and did not affect the GAs level; however, it increased the ABA content in embryos before germination was completed. Ascorbic acid, sodium benzoate and tiron, scavengers of reactive oxygen species (ROS), reduced the stimulatory effect of NO on caryopsis germination. This work provides new insight on the participation of NO in releasing A. fatua caryopses dormancy and on the relationship of NO with endogenous ABA and GAs.
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Affiliation(s)
- Jan Kępczyński
- Institute of Biology, University of Szczecin, Wąska 13, 71-415, Szczecin, Poland.
| | - Agata Wójcik
- Institute of Biology, University of Szczecin, Wąska 13, 71-415, Szczecin, Poland
| | - Michał Dziurka
- Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 20-239, Krakow, Poland
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7
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Loades E, Pérez M, Turečková V, Tarkowská D, Strnad M, Seville A, Nakabayashi K, Leubner-Metzger G. Distinct hormonal and morphological control of dormancy and germination in Chenopodium album dimorphic seeds. FRONTIERS IN PLANT SCIENCE 2023; 14:1156794. [PMID: 37063214 PMCID: PMC10098365 DOI: 10.3389/fpls.2023.1156794] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 03/14/2023] [Indexed: 06/19/2023]
Abstract
Dormancy and heteromorphism are innate seed properties that control germination timing through adaptation to the prevailing environment. The degree of variation in dormancy depth within a seed population differs considerably depending on the genotype and maternal environment. Dormancy is therefore a key trait of annual weeds to time seedling emergence across seasons. Seed heteromorphism, the production of distinct seed morphs (in color, mass or other morphological characteristics) on the same individual plant, is considered to be a bet-hedging strategy in unpredictable environments. Heteromorphic species evolved independently in several plant families and the distinct seed morphs provide an additional degree of variation. Here we conducted a comparative morphological and molecular analysis of the dimorphic seeds (black and brown) of the Amaranthaceae weed Chenopodium album. Freshly harvested black and brown seeds differed in their dormancy and germination responses to ambient temperature. The black seed morph of seedlot #1 was dormant and 2/3rd of the seed population had non-deep physiological dormancy which was released by after-ripening (AR) or gibberellin (GA) treatment. The deeper dormancy of the remaining 1/3rd non-germinating seeds required in addition ethylene and nitrate for its release. The black seeds of seedlot #2 and the brown seed morphs of both seedlots were non-dormant with 2/3rd of the seeds germinating in the fresh mature state. The dimorphic seeds and seedlots differed in testa (outer seed coat) thickness in that thick testas of black seeds of seedlot #1 conferred coat-imposed dormancy. The dimorphic seeds and seedlots differed in their abscisic acid (ABA) and GA contents in the dry state and during imbibition in that GA biosynthesis was highest in brown seeds and ABA degradation was faster in seedlot #2. Chenopodium genes for GA and ABA metabolism were identified and their distinct transcript expression patterns were quantified in dry and imbibed C. album seeds. Phylogenetic analyses of the Amaranthaceae sequences revealed a high proportion of expanded gene families within the Chenopodium genus. The identified hormonal, molecular and morphological mechanisms and dormancy variation of the dimorphic seeds of C. album and other Amaranthaceae are compared and discussed as adaptations to variable and stressful environments.
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Affiliation(s)
- Eddison Loades
- Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | - Marta Pérez
- Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | - Veronika Turečková
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc, Czechia
| | - Danuše Tarkowská
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc, Czechia
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc, Czechia
| | - Anne Seville
- Crop Protection Research, Syngenta, Jealott’s Hill International Research Centre, Bracknell, United Kingdom
| | - Kazumi Nakabayashi
- Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | - Gerhard Leubner-Metzger
- Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc, Czechia
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8
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Bin Rahman ANMR, Ding W, Zhang J. The absorption of water from humid air by grass embryos during germination. PLANT PHYSIOLOGY 2022; 189:1435-1449. [PMID: 35512056 PMCID: PMC9237686 DOI: 10.1093/plphys/kiac179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
Grass embryos possess structures that do not occur in any other flowering plants. Due to the specific embryo structure and position, grass embryo surfaces may be exposed to surrounding air under partial caryopsis-soil contact conditions, but whether caryopses of the grass family (Poaceae) can sense soil air humidity to initiate successful germination under partial caryopsis-soil contact conditions remain unknown. Here, we found that grass embryos have the unique ability to absorb water from atmospheric water vapor under partial caryopsis-soil contact conditions. To absorb atmospheric moisture, grass embryos developed profuse and highly elongated hairs on the embryo surface. These hairs, classically known as coleorhiza hairs, developed only on the embryo surface exposed to humid air, and submergence of the embryo surface inhibited their development. In addition to humid air-dependent development, almost all other developmental features of coleorhiza hairs were substantially different from root hairs. However, coleorhiza hair development was regulated by ROOTHAIRLESS 1. Besides the genetic control of coleorhiza hair development, we also identified how caryopses manage to keep the hairs turgid in natural open environments as the hairs were highly sensitive to dry air exposure. Moreover, we video-documented the regulation of developmental processes. The unique humid air-dependent coleorhiza hair development and their ability to absorb water from water vapor present in microsites or soil air give grasses advantages in germination and seedling establishment. Ultimately, coleorhiza hairs may have contributed to the ecological success of the grass family.
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Affiliation(s)
- A N M Rubaiyath Bin Rahman
- Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong, People’s Republic of China
| | - Wona Ding
- College of Science and Technology, Ningbo University, Ningbo 315211, People’s Republic of China
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9
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Grainge G, Nakabayashi K, Steinbrecher T, Kennedy S, Ren J, Iza F, Leubner-Metzger G. Molecular mechanisms of seed dormancy release by gas plasma-activated water technology. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4065-4078. [PMID: 35427417 PMCID: PMC9232203 DOI: 10.1093/jxb/erac150] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/13/2022] [Indexed: 06/14/2023]
Abstract
Developing innovative agri-technologies is essential for the sustainable intensification of global food production. Seed dormancy is an adaptive trait which defines the environmental conditions in which the seed is able to germinate. Dormancy release requires sensing and integration of multiple environmental signals, a complex process which may be mimicked by seed treatment technologies. Here, we reveal molecular mechanisms by which non-thermal (cold) atmospheric gas plasma-activated water (GPAW) releases the physiological seed dormancy of Arabidopsis thaliana. GPAW triggered dormancy release by synergistic interaction between plasma-generated reactive chemical species (NO3-, H2O2, ·NO, and ·OH) and multiple signalling pathways targeting gibberellin and abscisic acid (ABA) metabolism and the expression of downstream cell wall-remodelling genes. Direct chemical action of GPAW on cell walls resulted in premature biomechanical endosperm weakening. The germination responses of dormancy signalling (nlp8, prt6, and dog1) and ABA metabolism (cyp707a2) mutants varied with GPAW composition. GPAW removes seed dormancy blocks by triggering multiple molecular signalling pathways combined with direct chemical tissue weakening to permit seed germination. Gas plasma technologies therefore improve seed quality by mimicking permissive environments in which sensing and integration of multiple signals lead to dormancy release and germination.
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Affiliation(s)
- Giles Grainge
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Kazumi Nakabayashi
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Tina Steinbrecher
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Sue Kennedy
- Elsoms Seeds Ltd, Spalding, Lincolnshire PE11 1QG, UK
| | - Junchen Ren
- Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Leicestershire LE11 3TU, UK
| | - Felipe Iza
- Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Leicestershire LE11 3TU, UK
- Division of Advanced Nuclear Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk 790-784, South Korea
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10
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The Phytotoxin Myrigalone A Triggers a Phased Detoxification Programme and Inhibits Lepidium sativum Seed Germination via Multiple Mechanisms including Interference with Auxin Homeostasis. Int J Mol Sci 2022; 23:ijms23094618. [PMID: 35563008 PMCID: PMC9104956 DOI: 10.3390/ijms23094618] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 02/01/2023] Open
Abstract
Molecular responses of plants to natural phytotoxins comprise more general and compound-specific mechanisms. How phytotoxic chalcones and other flavonoids inhibit seedling growth was widely studied, but how they interfere with seed germination is largely unknown. The dihydrochalcone and putative allelochemical myrigalone A (MyA) inhibits seed germination and seedling growth. Transcriptome (RNAseq) and hormone analyses of Lepidium sativum seed responses to MyA were compared to other bioactive and inactive compounds. MyA treatment of imbibed seeds triggered the phased induction of a detoxification programme, altered gibberellin, cis-(+)-12-oxophytodienoic acid and jasmonate metabolism, and affected the expression of hormone transporter genes. The MyA-mediated inhibition involved interference with the antioxidant system, oxidative signalling, aquaporins and water uptake, but not uncoupling of oxidative phosphorylation or p-hydroxyphenylpyruvate dioxygenase expression/activity. MyA specifically affected the expression of auxin-related signalling genes, and various transporter genes, including for auxin transport (PIN7, ABCG37, ABCG4, WAT1). Responses to auxin-specific inhibitors further supported the conclusion that MyA interferes with auxin homeostasis during seed germination. Comparative analysis of MyA and other phytotoxins revealed differences in the specific regulatory mechanisms and auxin transporter genes targeted to interfere with auxin homestasis. We conclude that MyA exerts its phytotoxic activity by multiple auxin-dependent and independent molecular mechanisms.
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11
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Hourston JE, Steinbrecher T, Chandler JO, Pérez M, Dietrich K, Turečková V, Tarkowská D, Strnad M, Weltmeier F, Meinhard J, Fischer U, Fiedler‐Wiechers K, Ignatz M, Leubner‐Metzger G. Cold-induced secondary dormancy and its regulatory mechanisms in Beta vulgaris. PLANT, CELL & ENVIRONMENT 2022; 45:1315-1332. [PMID: 35064681 PMCID: PMC9305896 DOI: 10.1111/pce.14264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 10/26/2021] [Accepted: 11/18/2021] [Indexed: 06/14/2023]
Abstract
The dynamic behaviour of seeds in soil seed banks depends on their ability to act as sophisticated environmental sensors to adjust their sensitivity thresholds for germination by dormancy mechanisms. Here we show that prolonged incubation of sugar beet fruits at low temperature (chilling at 5°C, generally known to release seed dormancy of many species) can induce secondary nondeep physiological dormancy of an apparently nondormant crop species. The physiological and biophysical mechanisms underpinning this cold-induced secondary dormancy include the chilling-induced accumulation of abscisic acid in the seeds, a reduction in the embryo growth potential and a block in weakening of the endosperm covering the embryonic root. Transcriptome analysis revealed distinct gene expression patterns in the different temperature regimes and upon secondary dormancy induction and maintenance. The chilling caused reduced expression of cell wall remodelling protein genes required for embryo cell elongation growth and endosperm weakening, as well as increased expression of seed maturation genes, such as for late embryogenesis abundant proteins. A model integrating the hormonal signalling and master regulator expression with the temperature-control of seed dormancy and maturation programmes is proposed. The revealed mechanisms of the cold-induced secondary dormancy are important for climate-smart agriculture and food security.
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Affiliation(s)
- James E. Hourston
- Department of Biological SciencesRoyal Holloway University of LondonEghamUK
| | - Tina Steinbrecher
- Department of Biological SciencesRoyal Holloway University of LondonEghamUK
| | - Jake O. Chandler
- Department of Biological SciencesRoyal Holloway University of LondonEghamUK
| | - Marta Pérez
- Department of Biological SciencesRoyal Holloway University of LondonEghamUK
| | | | - Veronika Turečková
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental BotanyCzech Academy of SciencesOlomoucCzech Republic
| | - Danuše Tarkowská
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental BotanyCzech Academy of SciencesOlomoucCzech Republic
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental BotanyCzech Academy of SciencesOlomoucCzech Republic
| | | | | | | | | | - Michael Ignatz
- Department of Biological SciencesRoyal Holloway University of LondonEghamUK
| | - Gerhard Leubner‐Metzger
- Department of Biological SciencesRoyal Holloway University of LondonEghamUK
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental BotanyCzech Academy of SciencesOlomoucCzech Republic
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12
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Steinbrecher T, Leubner-Metzger G. Xyloglucan remodelling enzymes and the mechanics of plant seed and fruit biology. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:1253-1257. [PMID: 35235657 PMCID: PMC8890615 DOI: 10.1093/jxb/erac020] [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] [Indexed: 06/14/2023]
Abstract
This article comments on: Di Marzo M, Ebeling Viana V, Banfi C, Cassina V, Corti R, Herrera-Ubaldo H, Babolin N, Guazzotti A, Kiegle E, Gregis V, de Folter S, Sampedro J, Mantegazza F, Colombo L, Ezquer I. 2022. Cell wall modifications by α-XYLOSIDASE1 are required for the control of seed and fruit size. Journal of Experimental Botany 73, 1499–1515.
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Affiliation(s)
- Tina Steinbrecher
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Gerhard Leubner-Metzger
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
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13
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Song T, Das D, Ye NH, Wang GQ, Zhu FY, Chen MX, Yang F, Zhang JH. Comparative transcriptome analysis of coleorhiza development in japonica and Indica rice. BMC PLANT BIOLOGY 2021; 21:514. [PMID: 34736393 PMCID: PMC8567703 DOI: 10.1186/s12870-021-03276-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 10/18/2021] [Indexed: 05/12/2023]
Abstract
BACKGROUND Coleorhiza hairs, are sheath-like outgrowth organs in the seeds of Poaceae family that look like root hair but develop from the coleorhiza epidermal cells during seed imbibition. The major role of coleorhiza hair in seed germination involves facilitating water uptake and nutrient supply for seed germination. However, molecular basis of coleorhiza hair development and underlying genes and metabolic pathways during seed germination are largely unknown and need to be established. RESULTS In this study, a comparative transcriptome analysis of coleorhiza hairs from japonica and indica rice suggested that DEGs in embryo samples from seeds with embryo in air (EIA) as compared to embryo from seeds completely covered by water (CBW) were enriched in water deprivation, abscisic acid (ABA) and auxin metabolism, carbohydrate catabolism and phosphorus metabolism in coleorhiza hairs in both cultivars. Up-regulation of key metabolic genes in ABA, auxin and dehydrin and aquaporin genes may help maintain the basic development of coleorhiza hair in japonica and indica in EIA samples during both early and late stages. Additionally, DEGs involved in glutathione metabolism and carbon metabolism are upregulated while DEGs involved in amino acid and nucleotide sugar metabolism are downregulated in EIA suggesting induction of oxidative stress-alleviating genes and less priority to primary metabolism. CONCLUSIONS Taken together, results in this study could provide novel aspects about the molecular signaling that could be involved in coleorhiza hair development in different types of rice cultivars during seed germination and may give some hints for breeders to improve seed germination efficiency under moderate drought conditions.
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Affiliation(s)
- Tao Song
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518057, China
| | - Debatosh Das
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518057, China
| | - Neng-Hui Ye
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, 410128, China
| | - Guan-Qun Wang
- Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong
| | - Fu-Yuan Zhu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China
| | - Mo-Xian Chen
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Feng Yang
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518057, China.
| | - Jian-Hua Zhang
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518057, China.
- Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong.
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong.
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14
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Walker M, Pérez M, Steinbrecher T, Gawthrop F, Pavlović I, Novák O, Tarkowská D, Strnad M, Marone F, Nakabayashi K, Leubner-Metzger G. Molecular mechanisms and hormonal regulation underpinning morphological dormancy: a case study using Apium graveolens (Apiaceae). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 108:1020-1036. [PMID: 34510583 DOI: 10.1111/tpj.15489] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 09/02/2021] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
Underdeveloped (small) embryos embedded in abundant endosperm tissue, and thus having morphological dormancy (MD) or morphophysiological dormancy (MPD), are considered to be the ancestral state in seed dormancy evolution. This trait is retained in the Apiaceae family, which provides excellent model systems for investigating the underpinning mechanisms. We investigated Apium graveolens (celery) MD by combined innovative imaging and embryo growth assays with the quantification of hormone metabolism, as well as the analysis of hormone and cell-wall related gene expression. The integrated experimental results demonstrated that embryo growth occurred inside imbibed celery fruits in association with endosperm degradation, and that a critical embryo size was required for radicle emergence. The regulation of these processes depends on gene expression leading to gibberellin and indole-3-acetic acid (IAA) production by the embryo and on crosstalk between the fruit compartments. ABA degradation associated with distinct spatiotemporal patterns in ABA sensitivity control embryo growth, endosperm breakdown and radicle emergence. This complex interaction between gibberellins, IAA and ABA metabolism, and changes in the tissue-specific sensitivities to these hormones is distinct from non-MD seeds. We conclude that the embryo growth to reach the critical size and the associated endosperm breakdown inside MD fruits constitute a unique germination programme.
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Affiliation(s)
- Matthew Walker
- Department of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK
- Tozer Seeds, Tozer Seeds Ltd, Cobham, KT11 3EH, UK
| | - Marta Pérez
- Department of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK
| | - Tina Steinbrecher
- Department of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK
| | | | - Iva Pavlović
- Laboratory of Growth Regulators, Institute of Experimental Botany, Czech Academy of Sciences and Faculty of Science, Palacký University Olomouc, Olomouc, CZ-78371, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany, Czech Academy of Sciences and Faculty of Science, Palacký University Olomouc, Olomouc, CZ-78371, Czech Republic
| | - Danuše Tarkowská
- Laboratory of Growth Regulators, Institute of Experimental Botany, Czech Academy of Sciences and Faculty of Science, Palacký University Olomouc, Olomouc, CZ-78371, Czech Republic
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Institute of Experimental Botany, Czech Academy of Sciences and Faculty of Science, Palacký University Olomouc, Olomouc, CZ-78371, Czech Republic
| | - Federica Marone
- Swiss Light Source, Paul Scherrer Institute, Villigen, CH-5232, Switzerland
| | - Kazumi Nakabayashi
- Department of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK
| | - Gerhard Leubner-Metzger
- Department of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK
- Laboratory of Growth Regulators, Institute of Experimental Botany, Czech Academy of Sciences and Faculty of Science, Palacký University Olomouc, Olomouc, CZ-78371, Czech Republic
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15
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Farooq MA, Zhang X, Zafar MM, Ma W, Zhao J. Roles of Reactive Oxygen Species and Mitochondria in Seed Germination. FRONTIERS IN PLANT SCIENCE 2021; 12:781734. [PMID: 34956279 PMCID: PMC8695494 DOI: 10.3389/fpls.2021.781734] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/18/2021] [Indexed: 05/14/2023]
Abstract
Seed germination is crucial for the life cycle of plants and maximum crop production. This critical developmental step is regulated by diverse endogenous [hormones, reactive oxygen species (ROS)] and exogenous (light, temperature) factors. Reactive oxygen species promote the release of seed dormancy by biomolecules oxidation, testa weakening and endosperm decay. Reactive oxygen species modulate metabolic and hormone signaling pathways that induce and maintain seed dormancy and germination. Endosperm provides nutrients and senses environmental signals to regulate the growth of the embryo by secreting timely signals. The growing energy demand of the developing embryo and endosperm is fulfilled by functional mitochondria. Mitochondrial matrix-localized heat shock protein GhHSP24.7 controls seed germination in a temperature-dependent manner. In this review, we summarize comprehensive view of biochemical and molecular mechanisms, which coordinately control seed germination. We also discuss that the accurate and optimized coordination of ROS, mitochondria, heat shock proteins is required to permit testa rupture and subsequent germination.
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Affiliation(s)
- Muhammad Awais Farooq
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding, China
- Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan
| | - Xiaomeng Zhang
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding, China
| | | | - Wei Ma
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding, China
- *Correspondence: Wei Ma,
| | - Jianjun Zhao
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding, China
- Jianjun Zhao,
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