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Leprince O, Pellizzaro A, Berriri S, Buitink J. Late seed maturation: drying without dying. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:827-841. [PMID: 28391329 DOI: 10.1093/jxb/erw363] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Besides the deposition of storage reserves, seed maturation is characterized by the acquisition of functional traits including germination, desiccation tolerance, dormancy, and longevity. After seed filling, seed longevity increases up to 30-fold, concomitant with desiccation that brings the embryo to a quiescent state. The period that we define as late maturation phase can represent 10-78% of total seed development time, yet it remains overlooked. Its importance is underscored by the fact that in the seed production chain, the stage of maturity at harvest is the primary factor that influences seed longevity and seedling establishment. This review describes the major events and regulatory pathways underlying the acquisition of seed longevity, focusing on key indicators of maturity such as chlorophyll degradation, accumulation of raffinose family oligosaccharides, late embryogenesis abundant proteins, and heat shock proteins. We discuss how these markers are correlated with or contribute to seed longevity, and highlight questions that merit further attention. We present evidence suggesting that molecular players involved in biotic defence also have a regulatory role in seed longevity. We also explore how the concept of plasticity can help understand the acquisition of longevity.
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Affiliation(s)
- Olivier Leprince
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 Quasav, 42 rue George Morel, 49071 Beaucouzé, France
| | - Anthoni Pellizzaro
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 Quasav, 42 rue George Morel, 49071 Beaucouzé, France
| | - Souha Berriri
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 Quasav, 42 rue George Morel, 49071 Beaucouzé, France
| | - Julia Buitink
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 Quasav, 42 rue George Morel, 49071 Beaucouzé, France
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52
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Chahtane H, Kim W, Lopez-Molina L. Primary seed dormancy: a temporally multilayered riddle waiting to be unlocked. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:857-869. [PMID: 27729475 DOI: 10.1093/jxb/erw377] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Primary seed dormancy is an important adaptive plant trait whereby seed germination is blocked under conditions that would otherwise be favorable for germination. This trait is found in newly produced mature seeds of many species, but not all. Once produced, dry seeds undergo an aging time period, called dry after-ripening, during which they lose primary dormancy and gradually acquire the capacity to germinate when exposed to favorable germination conditions. Primary seed dormancy has been extensively studied not only for its scientific interest but also for its ecological, phenological, and agricultural importance. Nevertheless, the mechanisms underlying primary seed dormancy and its regulation during after-ripening remain poorly understood. Here we review the principal developmental stages where primary dormancy is established and regulated prior to and during seed after-ripening, where it is progressively lost. We attempt to identify and summarize what is known about the molecular and genetic mechanisms intervening over time in each of these stages.
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Affiliation(s)
- Hicham Chahtane
- Department of Plant Biology and Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Woohyun Kim
- Department of Plant Biology and Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Luis Lopez-Molina
- Department of Plant Biology and Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
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53
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Piskurewicz U, Iwasaki M, Susaki D, Megies C, Kinoshita T, Lopez-Molina L. Dormancy-specific imprinting underlies maternal inheritance of seed dormancy in Arabidopsis thaliana. eLife 2016; 5. [PMID: 28005006 PMCID: PMC5243116 DOI: 10.7554/elife.19573] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 12/21/2016] [Indexed: 01/31/2023] Open
Abstract
Mature seed dormancy is a vital plant trait that prevents germination out of season. In Arabidopsis, the trait can be maternally regulated but the underlying mechanisms sustaining this regulation, its general occurrence and its biological significance among accessions are poorly understood. Upon seed imbibition, the endosperm is essential to repress the germination of dormant seeds. Investigation of genomic imprinting in the mature seed endosperm led us to identify a novel set of imprinted genes that are expressed upon seed imbibition. Remarkably, programs of imprinted gene expression are adapted according to the dormancy status of the seed. We provide direct evidence that imprinted genes play a role in regulating germination processes and that preferential maternal allelic expression can implement maternal inheritance of seed dormancy levels. DOI:http://dx.doi.org/10.7554/eLife.19573.001
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Affiliation(s)
- Urszula Piskurewicz
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Mayumi Iwasaki
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Daichi Susaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Christian Megies
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Luis Lopez-Molina
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
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54
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Zhang Q, Song X, Bartels D. Enzymes and Metabolites in Carbohydrate Metabolism of Desiccation Tolerant Plants. Proteomes 2016; 4:E40. [PMID: 28248249 PMCID: PMC5260972 DOI: 10.3390/proteomes4040040] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 12/01/2016] [Accepted: 12/07/2016] [Indexed: 01/31/2023] Open
Abstract
Resurrection plants can tolerate extreme water loss. Substantial sugar accumulation is a phenomenon in resurrection plants during dehydration. Sugars have been identified as one important factor contributing to desiccation tolerance. Phylogenetic diversity of resurrection plants reflects the diversity of sugar metabolism in response to dehydration. Sugars, which accumulate during dehydration, have been shown to protect macromolecules and membranes and to scavenge reactive oxygen species. This review focuses on the performance of enzymes participating in sugar metabolism during dehydration stress. The relation between sugar metabolism and other biochemical activities is discussed and open questions as well as potential experimental approaches are proposed.
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Affiliation(s)
- Qingwei Zhang
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Kirschallee 1, 53115 Bonn, Germany.
| | - Xiaomin Song
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Kirschallee 1, 53115 Bonn, Germany.
| | - Dorothea Bartels
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Kirschallee 1, 53115 Bonn, Germany.
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55
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Costa MCD, Farrant JM, Oliver MJ, Ligterink W, Buitink J, Hilhorst HMW. Key genes involved in desiccation tolerance and dormancy across life forms. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2016; 251:162-168. [PMID: 27593474 DOI: 10.1016/j.plantsci.2016.02.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 01/27/2016] [Accepted: 02/01/2016] [Indexed: 05/25/2023]
Abstract
Desiccation tolerance (DT, the ability of certain organisms to survive severe dehydration) was a key trait in the evolution of life in terrestrial environments. Likely, the development of desiccation-tolerant life forms was accompanied by the acquisition of dormancy or a dormancy-like stage as a second powerful adaptation to cope with variations in the terrestrial environment. These naturally stress tolerant life forms may be a good source of genetic information to generate stress tolerant crops to face a future with predicted higher occurrence of drought. By mining for key genes and mechanisms related to DT and dormancy conserved across different species and life forms, unique candidate key genes may be identified. Here we identify several of these putative key genes, shared among multiple organisms, encoding for proteins involved in protection, growth and energy metabolism. Mutating a selection of these genes in the model plant Arabidopsis thaliana resulted in clear DT-, dormancy- and other seed-associated phenotypes, showing the efficiency and power of our approach and paves the way for the development of drought-stress tolerant crops. Our analysis supports a co-evolution of DT and dormancy by shared mechanisms that favour survival and adaptation to ever-changing environments with strong seasonal fluctuations.
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Affiliation(s)
- Maria Cecília D Costa
- Wageningen Seed Lab, Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
| | - Jill M Farrant
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag, Rondebosch 7701, South Africa
| | - Melvin J Oliver
- U.S. Department of Agriculture-ARS-MWA-PGRU, 205 Curtis Hall, University of Missouri, Columbia, MO 65211, USA
| | - Wilco Ligterink
- Wageningen Seed Lab, Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Julia Buitink
- Institut National de la Recherch Agronomique, UMR 1345 Institut de Recherche en Horticulture et Semences, SFR 4207 Qualité et Santé du Végétal, 49045 Angers, France
| | - Henk M W Hilhorst
- Wageningen Seed Lab, Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
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56
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Vesty EF, Saidi Y, Moody LA, Holloway D, Whitbread A, Needs S, Choudhary A, Burns B, McLeod D, Bradshaw SJ, Bae H, King BC, Bassel GW, Simonsen HT, Coates JC. The decision to germinate is regulated by divergent molecular networks in spores and seeds. THE NEW PHYTOLOGIST 2016; 211:952-66. [PMID: 27257104 PMCID: PMC4950004 DOI: 10.1111/nph.14018] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 04/16/2016] [Indexed: 05/15/2023]
Abstract
Dispersal is a key step in land plant life cycles, usually via formation of spores or seeds. Regulation of spore- or seed-germination allows control over the timing of transition from one generation to the next, enabling plant dispersal. A combination of environmental and genetic factors determines when seed germination occurs. Endogenous hormones mediate this decision in response to the environment. Less is known about how spore germination is controlled in earlier-evolving nonseed plants. Here, we present an in-depth analysis of the environmental and hormonal regulation of spore germination in the model bryophyte Physcomitrella patens (Aphanoregma patens). Our data suggest that the environmental signals regulating germination are conserved, but also that downstream hormone integration pathways mediating these responses in seeds were acquired after the evolution of the bryophyte lineage. Moreover, the role of abscisic acid and diterpenes (gibberellins) in germination assumed much greater importance as land plant evolution progressed. We conclude that the endogenous hormone signalling networks mediating germination in response to the environment may have evolved independently in spores and seeds. This paves the way for future research about how the mechanisms of plant dispersal on land evolved.
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Affiliation(s)
- Eleanor F. Vesty
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Younousse Saidi
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Laura A. Moody
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Daniel Holloway
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Amy Whitbread
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Sarah Needs
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Anushree Choudhary
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Bethany Burns
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Daniel McLeod
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Susan J. Bradshaw
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Hansol Bae
- Department of Systems BiologyTechnical University of DenmarkSøltofts Plads, 2800 KgsLyngbyDenmark
| | - Brian Christopher King
- Department of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 40Frederiksberg C1871Denmark
| | - George W. Bassel
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Henrik Toft Simonsen
- Department of Systems BiologyTechnical University of DenmarkSøltofts Plads, 2800 KgsLyngbyDenmark
| | - Juliet C. Coates
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
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57
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Rezki S, Campion C, Iacomi-Vasilescu B, Preveaux A, Toualbia Y, Bonneau S, Briand M, Laurent E, Hunault G, Simoneau P, Jacques MA, Barret M. Differences in stability of seed-associated microbial assemblages in response to invasion by phytopathogenic microorganisms. PeerJ 2016; 4:e1923. [PMID: 27077013 PMCID: PMC4830237 DOI: 10.7717/peerj.1923] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/21/2016] [Indexed: 11/20/2022] Open
Abstract
Seeds are involved in the vertical transmission of microorganisms from one plant generation to another and consequently act as reservoirs for the plant microbiota. However, little is known about the structure of seed-associated microbial assemblages and the regulators of assemblage structure. In this work, we have assessed the response of seed-associated microbial assemblages of Raphanus sativus to invading phytopathogenic agents, the bacterial strain Xanthomonas campestris pv. campestris (Xcc) 8004 and the fungal strain Alternaria brassicicola Abra43. According to the indicators of bacterial (16S rRNA gene and gyrB sequences) and fungal (ITS1) diversity employed in this study, seed transmission of the bacterial strain Xcc 8004 did not change the overall composition of resident microbial assemblages. In contrast seed transmission of Abra43 strongly modified the richness and structure of fungal assemblages without affecting bacterial assemblages. The sensitivity of seed-associated fungal assemblage to Abra43 is mostly related to changes in relative abundance of closely related fungal species that belong to the Alternaria genus. Variation in stability of the seed microbiota in response to Xcc and Abra43 invasions could be explained by differences in seed transmission pathways employed by these micro-organisms, which ultimately results in divergence in spatio-temporal colonization of the seed habitat.
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Affiliation(s)
- Samir Rezki
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Claire Campion
- Institut de Recherche en Horticulture et Semences, Université d'Angers , Beaucouzé , France
| | | | - Anne Preveaux
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Youness Toualbia
- Institut de Recherche en Horticulture et Semences, Université d'Angers , Beaucouzé , France
| | - Sophie Bonneau
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Martial Briand
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Emmanuelle Laurent
- Federation Nationale des Agriculteurs Multiplicateurs de Semences , Brain sur l'Authion , France
| | - Gilles Hunault
- Laboratoire d'Hémodynamique, Interaction Fibrose et Invasivité tumorale Hépatique, Université d'Angers , Angers , France
| | - Philippe Simoneau
- Institut de Recherche en Horticulture et Semences, Université d'Angers , Beaucouzé , France
| | - Marie-Agnès Jacques
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Matthieu Barret
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
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58
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Dekkers BJW, He H, Hanson J, Willems LAJ, Jamar DCL, Cueff G, Rajjou L, Hilhorst HWM, Bentsink L. The Arabidopsis DELAY OF GERMINATION 1 gene affects ABSCISIC ACID INSENSITIVE 5 (ABI5) expression and genetically interacts with ABI3 during Arabidopsis seed development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 85:451-65. [PMID: 26729600 DOI: 10.1111/tpj.13118] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 12/22/2015] [Accepted: 12/23/2015] [Indexed: 05/18/2023]
Abstract
The seed expressed gene DELAY OF GERMINATION (DOG) 1 is absolutely required for the induction of dormancy. Next to a non-dormant phenotype, the dog1-1 mutant is also characterized by a reduced seed longevity suggesting that DOG1 may affect additional seed processes as well. This aspect however, has been hardly studied and is poorly understood. To uncover additional roles of DOG1 in seeds we performed a detailed analysis of the dog1 mutant using both transcriptomics and metabolomics to investigate the molecular consequences of a dysfunctional DOG1 gene. Further, we used a genetic approach taking advantage of the weak aba insensitive (abi) 3-1 allele as a sensitized genetic background in a cross with dog1-1. DOG1 affects the expression of hundreds of genes including LATE EMBRYOGENESIS ABUNDANT and HEAT SHOCK PROTEIN genes which are affected by DOG1 partly via control of ABI5 expression. Furthermore, the content of a subset of primary metabolites, which normally accumulate during seed maturation, was found to be affected in the dog1-1 mutant. Surprisingly, the abi3-1 dog1-1 double mutant produced green seeds which are highly ABA insensitive, phenocopying severe abi3 mutants, indicating that dog1-1 acts as an enhancer of the weak abi3-1 allele and thus revealing a genetic interaction between both genes. Analysis of the dog1 and dog1 abi3 mutants revealed additional seed phenotypes and therefore we hypothesize that DOG1 function is not limited to dormancy but that it is required for multiple aspects of seed maturation, in part by interfering with ABA signalling components.
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Affiliation(s)
- Bas J W Dekkers
- Wageningen Seed Laboratory, Wageningen University, Droevendaalsesteeg 1, NL-6708 PB, Wageningen, The Netherlands
- Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, NL-6708, PB Wageningen, The Netherlands
- Department of Molecular Plant Physiology, Utrecht University, NL-3584 CH, Utrecht, The Netherlands
| | - Hanzi He
- Wageningen Seed Laboratory, Wageningen University, Droevendaalsesteeg 1, NL-6708 PB, Wageningen, The Netherlands
- Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, NL-6708, PB Wageningen, The Netherlands
| | - Johannes Hanson
- Department of Molecular Plant Physiology, Utrecht University, NL-3584 CH, Utrecht, The Netherlands
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, SE-90187, Umeå, Sweden
| | - Leo A J Willems
- Wageningen Seed Laboratory, Wageningen University, Droevendaalsesteeg 1, NL-6708 PB, Wageningen, The Netherlands
- Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, NL-6708, PB Wageningen, The Netherlands
| | - Diaan C L Jamar
- Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, NL-6708, PB Wageningen, The Netherlands
| | - Gwendal Cueff
- INRA, Institut Jean-Pierre Bourgin (IJPB), UMR 1318 INRA/AgroParisTech, ERL CNRS 3559, Université Paris-Saclay, 'Saclay Plant Sciences' - RD10, F-78026, Versailles, France
- Chair of Plant Physiology, AgroParisTech, 16 rue Claude Bernard, F-75231, Paris Cedex 05, France
| | - Loïc Rajjou
- INRA, Institut Jean-Pierre Bourgin (IJPB), UMR 1318 INRA/AgroParisTech, ERL CNRS 3559, Université Paris-Saclay, 'Saclay Plant Sciences' - RD10, F-78026, Versailles, France
- Chair of Plant Physiology, AgroParisTech, 16 rue Claude Bernard, F-75231, Paris Cedex 05, France
| | - Henk W M Hilhorst
- Wageningen Seed Laboratory, Wageningen University, Droevendaalsesteeg 1, NL-6708 PB, Wageningen, The Netherlands
- Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, NL-6708, PB Wageningen, The Netherlands
| | - Leónie Bentsink
- Wageningen Seed Laboratory, Wageningen University, Droevendaalsesteeg 1, NL-6708 PB, Wageningen, The Netherlands
- Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, NL-6708, PB Wageningen, The Netherlands
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59
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Walters C. Orthodoxy, recalcitrance and in-between: describing variation in seed storage characteristics using threshold responses to water loss. PLANTA 2015; 242:397-406. [PMID: 25985842 DOI: 10.1007/s00425-015-2312-6] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 04/20/2015] [Indexed: 05/15/2023]
Abstract
Discrete categories of seed physiology can be explained through a unified concept of the structural and molecular mobility responses within cells to drying. Tolerance of desiccation is typically described by a threshold or low water content limit to survival. This convention provides fairly good distinction between orthodox and recalcitrant seeds, which show thresholds of less than about 0.07 and greater than about 0.2 g H2O g DW(-1), respectively. Threshold water contents, however, are not direct measures of the intensity of water stress tolerated by seeds, nor are they measures of cell response to water stress. More direct criteria, that accommodate both spatial and temporal effects of water loss, are required to explain variation of desiccation tolerance and longevity in seeds from diverse genetic backgrounds and growth conditions. This essay presents the argument that changes in cellular volume directly quantify primary responses to desiccating stress in a context that also links damage, as cellular constituents compress, and protection, as compressed molecules form stabilizing structure. During desiccation, fluid cytoplasm solidifies, and the newly formed spatial relationships among molecules determine whether and how long viability is maintained. The diversity of seed behaviors suggests complexity and opportunity to discover molecules and mechanisms that regulate survival and perception of time in cells that lack metabolic function.
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Affiliation(s)
- Christina Walters
- USDA-ARS, National Center for Genetic Resources Preservation, 1111 South Mason Street, Fort Collins, CO, 80521, USA,
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