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Filipe JC, Ahrens CC, Byrne M, Hardy G, Rymer PD. Germination temperature sensitivity differs between co-occurring tree species and climate origins resulting in contrasting vulnerability to global warming. PLANT-ENVIRONMENT INTERACTIONS (HOBOKEN, N.J.) 2023; 4:146-162. [PMID: 37362420 PMCID: PMC10290426 DOI: 10.1002/pei3.10108] [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: 11/15/2022] [Revised: 03/20/2023] [Accepted: 04/04/2023] [Indexed: 06/28/2023]
Abstract
Climate change is shifting temperatures from historical patterns, globally impacting forest composition and resilience. Seed germination is temperature-sensitive, making the persistence of populations and colonization of available habitats vulnerable to warming. This study assessed germination response to temperature in foundation trees in south-western Australia's Mediterranean-type climate forests (Eucalyptus marginata (jarrah) and Corymbia calophylla (marri)) to estimate the thermal niche and vulnerability among populations. Seeds from the species' entire distribution were collected from 12 co-occurring populations. Germination thermal niche was investigated using a thermal gradient plate (5-40°C). Five constant temperatures between 9 and 33°C were used to test how the germination niche (1) differs between species, (2) varies among populations, and (3) relates to the climate of origin. Germination response differed among species; jarrah had a lower optimal temperature and thermal limit than marri (T o 15.3°C, 21.2°C; ED50 23.4°C, 31°C, respectively). The thermal limit for germination differed among populations within both species, yet only marri showed evidence for adaptation to thermal origins. While marri has the capacity for germination at higher thermal temperatures, jarrah is more vulnerable to global warming exceeding safety margins. This discrepancy is predicted to alter species distributions and forest composition in the future.
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Affiliation(s)
- João C. Filipe
- Department of Biodiversity, Conservation and AttractionsBiodiversity and Conservation SciencePerthWestern AustraliaAustralia
- Centre for Terrestrial Ecosystem Science and SustainabilityHarry Butler InstituteMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Collin C. Ahrens
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityRichmondNew South WalesAustralia
- School of Biotechnology & Biomolecular SciencesUniversity of New South WalesSydneyNew South WalesAustralia
- Research Centre for Ecosystem ResilienceRoyal Botanic Gardens and Domain TrustSydneyNew South WalesAustralia
- Cesar AustraliaBrunswickVictoriaAustralia
| | - Margaret Byrne
- Department of Biodiversity, Conservation and AttractionsBiodiversity and Conservation SciencePerthWestern AustraliaAustralia
| | - Giles Hardy
- Centre for Terrestrial Ecosystem Science and SustainabilityHarry Butler InstituteMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Paul D. Rymer
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityRichmondNew South WalesAustralia
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2
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Collette JC, Sommerville KD, Lyons MB, Offord CA, Errington G, Newby ZJ, von Richter L, Emery NJ. Stepping up to the thermogradient plate: a data framework for predicting seed germination under climate change. ANNALS OF BOTANY 2022; 129:787-794. [PMID: 35212713 PMCID: PMC9292609 DOI: 10.1093/aob/mcac026] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 02/24/2022] [Indexed: 05/29/2023]
Abstract
BACKGROUND AND AIMS Seed germination is strongly influenced by environmental temperatures. With global temperatures predicted to rise, the timing of germination for thousands of plant species could change, leading to potential decreases in fitness and ecosystem-wide impacts. The thermogradient plate (TGP) is a powerful but underutilized research tool that tests germination under a broad range of constant and alternating temperatures, giving researchers the ability to predict germination characteristics using current and future climates. Previously, limitations surrounding experimental design and data analysis methods have discouraged its use in seed biology research. METHODS Here, we have developed a freely available R script that uses TGP data to analyse seed germination responses to temperature. We illustrate this analysis framework using three example species: Wollemia nobilis, Callitris baileyi and Alectryon subdentatus. The script generates >40 germination indices including germination rates and final germination across each cell of the TGP. These indices are then used to populate generalized additive models and predict germination under current and future monthly maximum and minimum temperatures anywhere on the globe. KEY RESULTS In our study species, modelled data were highly correlated with observed data, allowing confident predictions of monthly germination patterns for current and future climates. Wollemia nobilis germinated across a broad range of temperatures and was relatively unaffected by predicted future temperatures. In contrast, C. baileyi and A. subdentatus showed strong seasonal temperature responses, and the timing for peak germination was predicted to shift seasonally under future temperatures. CONCLUSIONS Our experimental workflow is a leap forward in the analysis of TGP experiments, increasing its many potential benefits, thereby improving research predictions and providing substantial information to inform management and conservation of plant species globally.
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Affiliation(s)
| | - Karen D Sommerville
- The Australian PlantBank, Australian Institute of Botanical Science, Australian Botanic Garden, Mount Annan, NSW 2567, Australia
| | - Mitchell B Lyons
- Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, Sydney NSW 2052, Australia
| | - Catherine A Offord
- The Australian PlantBank, Australian Institute of Botanical Science, Australian Botanic Garden, Mount Annan, NSW 2567, Australia
- Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, Sydney NSW 2052, Australia
| | - Graeme Errington
- The Australian PlantBank, Australian Institute of Botanical Science, Australian Botanic Garden, Mount Annan, NSW 2567, Australia
| | - Zoe-Joy Newby
- The Australian PlantBank, Australian Institute of Botanical Science, Australian Botanic Garden, Mount Annan, NSW 2567, Australia
| | - Lotte von Richter
- The Australian PlantBank, Australian Institute of Botanical Science, Australian Botanic Garden, Mount Annan, NSW 2567, Australia
| | - Nathan J Emery
- The Australian PlantBank, Australian Institute of Botanical Science, Australian Botanic Garden, Mount Annan, NSW 2567, Australia
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3
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Seed germination and vigor: ensuring crop sustainability in a changing climate. Heredity (Edinb) 2022; 128:450-459. [PMID: 35013549 DOI: 10.1038/s41437-022-00497-2] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 12/29/2021] [Accepted: 01/02/2022] [Indexed: 11/08/2022] Open
Abstract
In the coming decades, maintaining a steady food supply for the increasing world population will require high-yielding crop plants which can be productive under increasingly variable conditions. Maintaining high yields will require the successful and uniform establishment of plants in the field under altered environmental conditions. Seed vigor, a complex agronomic trait that includes seed longevity, germination speed, seedling growth, and early stress tolerance, determines the duration and success of this establishment period. Elevated temperature during early seed development can decrease seed size, number, and fertility, delay germination and reduce seed vigor in crops such as cereals, legumes, and vegetable crops. Heat stress in mature seeds can reduce seed vigor in crops such as lettuce, oat, and chickpea. Warming trends and increasing temperature variability can increase seed dormancy and reduce germination rates, especially in crops that require lower temperatures for germination and seedling establishment. To improve seed germination speed and success, much research has focused on selecting quality seeds for replanting, priming seeds before sowing, and breeding varieties with improved seed performance. Recent strides in understanding the genetic basis of variation in seed vigor have used genomics and transcriptomics to identify candidate genes for improving germination, and several studies have explored the potential impact of climate change on the percentage and timing of germination. In this review, we discuss these recent advances in the genetic underpinnings of seed performance as well as how climate change is expected to affect vigor in current varieties of staple, vegetable, and other crops.
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Fernández-Pascual E, Carta A, Mondoni A, Cavieres LA, Rosbakh S, Venn S, Satyanti A, Guja L, Briceño VF, Vandelook F, Mattana E, Saatkamp A, Bu H, Sommerville K, Poschlod P, Liu K, Nicotra A, Jiménez-Alfaro B. The seed germination spectrum of alpine plants: a global meta-analysis. THE NEW PHYTOLOGIST 2021; 229:3573-3586. [PMID: 33205452 DOI: 10.1111/nph.17086] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/11/2020] [Indexed: 06/11/2023]
Abstract
Assumptions about the germination ecology of alpine plants are presently based on individual species and local studies. A current challenge is to synthesise, at the global level, the alpine seed ecological spectrum. We performed a meta-analysis of primary data from laboratory experiments conducted across four continents (excluding the tropics) and 661 species, to estimate the influence of six environmental cues on germination proportion, mean germination time and germination synchrony; accounting for seed morphology (mass, embryo : seed ratio) and phylogeny. Most alpine plants show physiological seed dormancy, a strong need for cold stratification, warm-cued germination and positive germination responses to light and alternating temperatures. Species restricted to the alpine belt have a higher preference for warm temperatures and a stronger response to cold stratification than species whose distribution extends also below the treeline. Seed mass, embryo size and phylogeny have strong constraining effects on germination responses to the environment. Globally, overwintering and warm temperatures are key drivers of germination in alpine habitats. The interplay between germination physiology and seed morphological traits further reflects pressures to avoid frost or drought stress. Our results indicate the convergence, at the global level, of the seed germination patterns of alpine species.
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Affiliation(s)
| | - Angelino Carta
- Dipartimento di Biologia, Botany Unit, University of Pisa, Pisa, 56126, Italy
| | - Andrea Mondoni
- Department of Earth and Environmental Sciences, University of Pavia, Pavia, 27100, Italy
| | - Lohengrin A Cavieres
- Departamento de Botánica|Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, 4070386, Chile
- Chile and Institute of Ecology and Biodiversity (IEB), Santiago, Chile
| | - Sergey Rosbakh
- Chair of Ecology and Conservation Biology, Institute of Plant Sciences, University of Regensburg, Regensburg, 93053, Germany
| | - Susanna Venn
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria, 3125, Australia
| | - Annisa Satyanti
- Division of Ecology & Evolution, Research School of Biology, The Australian National University, Canberra, ACT, 2600, Australia
| | - Lydia Guja
- Centre for Australian National Biodiversity Research, a joint venture between Parks Australia and CSIRO, Canberra, ACT, 2601, Australia
- National Seed Bank, Australian National Botanic Gardens, Canberra, ACT, 2601, Australia
| | | | | | - Efisio Mattana
- Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Ardingly, RH17 6TN, UK
| | - Arne Saatkamp
- Aix Marseille Université, Université d'Avignon, CNRS, IRD, IMBE, Facultés St Jérôme, case 421, Marseille, 13397, France
| | - Haiyan Bu
- State Key Laboratory of Grassland Agro-Ecosystems, Lanzhou University, Lanzhou, 730000, China
| | - Karen Sommerville
- The Australian PlantBank, Australian Institute of Botanical Science, The Royal Botanic Gardens & Domain Trust, Mount Annan, NSW, 2567, Australia
| | - Peter Poschlod
- Chair of Ecology and Conservation Biology, Institute of Plant Sciences, University of Regensburg, Regensburg, 93053, Germany
| | - Kun Liu
- State Key Laboratory of Grassland Agro-Ecosystems, Lanzhou University, Lanzhou, 730000, China
| | - Adrienne Nicotra
- Division of Ecology & Evolution, Research School of Biology, The Australian National University, Canberra, ACT, 2600, Australia
| | - Borja Jiménez-Alfaro
- Research Unit of Biodiversity (CSUC/UO/PA), University of Oviedo, Mieres, 33600, Spain
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5
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Klupczyńska EA, Pawłowski TA. Regulation of Seed Dormancy and Germination Mechanisms in a Changing Environment. Int J Mol Sci 2021; 22:1357. [PMID: 33572974 PMCID: PMC7866424 DOI: 10.3390/ijms22031357] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 01/10/2023] Open
Abstract
Environmental conditions are the basis of plant reproduction and are the critical factors controlling seed dormancy and germination. Global climate change is currently affecting environmental conditions and changing the reproduction of plants from seeds. Disturbances in germination will cause disturbances in the diversity of plant communities. Models developed for climate change scenarios show that some species will face a significant decrease in suitable habitat area. Dormancy is an adaptive mechanism that affects the probability of survival of a species. The ability of seeds of many plant species to survive until dormancy recedes and meet the requirements for germination is an adaptive strategy that can act as a buffer against the negative effects of environmental heterogeneity. The influence of temperature and humidity on seed dormancy status underlines the need to understand how changing environmental conditions will affect seed germination patterns. Knowledge of these processes is important for understanding plant evolution and adaptation to changes in the habitat. The network of genes controlling seed dormancy under the influence of environmental conditions is not fully characterized. Integrating research techniques from different disciplines of biology could aid understanding of the mechanisms of the processes controlling seed germination. Transcriptomics, proteomics, epigenetics, and other fields provide researchers with new opportunities to understand the many processes of plant life. This paper focuses on presenting the adaptation mechanism of seed dormancy and germination to the various environments, with emphasis on their prospective roles in adaptation to the changing climate.
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Affiliation(s)
| | - Tomasz A. Pawłowski
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland;
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Porceddu M, Pritchard HW, Mattana E, Bacchetta G. Differential Interpretation of Mountain Temperatures by Endospermic Seeds of Three Endemic Species Impacts the Timing of In Situ Germination. PLANTS (BASEL, SWITZERLAND) 2020; 9:E1382. [PMID: 33081420 PMCID: PMC7603068 DOI: 10.3390/plants9101382] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 11/18/2022]
Abstract
Predicting seed germination in the field is a critical part of anticipating the impact of climate change on the timing of wild species regeneration. We combined thermal time and soil heat sum models of seed germination for three endemic Mediterranean mountain species with endospermic seeds and morphophysiological dormancy: Aquilegia barbaricina, Paeonia corsica, and Ribes sandalioticum. Seeds were buried in the soil within the respective collection sites, both underneath and outside the tree canopy, and their growth was assessed regularly and related to soil temperatures and estimates of the thermal characteristics of the seeds. The thermal thresholds for embryo growth and seed germination of A. barbaricina assessed in previous studies under controlled conditions were used to calculate soil heat sum accumulation of this species in the field. Thermal thresholds of seed germination for P. corsica and R. sandalioticum were not previously known and were estimated for the first time in this field study, based on findings of previous works carried out under controlled conditions. Critical embryo length and maximum germination for A. barbaricina were reached in April, and in December for R. sandalioticum. Seeds of P. corsica stay dormant in the ground until the following summer, and the critical embryo length and highest germination were detected from September to December. Soil heat sum models predicted earlier germination by one month for all three species under two Intergovernmental Panel on Climate Change (IPCC) scenarios, based on the assumption that the estimated thermal thresholds will remain constant through climate changes. This phenological shift may increase the risk of mortality for young seedlings. The models developed provide important means of connecting the micro-environmental niche for in situ seed germination and the macro-environmental parameters under a global warming scenario.
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Affiliation(s)
- Marco Porceddu
- Sardinian Germplasm Bank (BG-SAR), Hortus Botanicus Karalitanus (HBK), University of Cagliari, Viale S. Ignazio da Laconi, 9-11, 09123 Cagliari, Italy;
- Centre for the Conservation of Biodiversity (CCB), Life and Environmental Sciences Department, University of Cagliari, Viale S. Ignazio da Laconi 11-13, 09123 Cagliari, Italy
| | - Hugh W. Pritchard
- Royal Botanic Gardens, Kew, Wellcome Trust Millennium Building, Wakehurst, Ardingly, West Sussex RH17 6TN, UK; (H.W.P.); (E.M.)
| | - Efisio Mattana
- Royal Botanic Gardens, Kew, Wellcome Trust Millennium Building, Wakehurst, Ardingly, West Sussex RH17 6TN, UK; (H.W.P.); (E.M.)
| | - Gianluigi Bacchetta
- Sardinian Germplasm Bank (BG-SAR), Hortus Botanicus Karalitanus (HBK), University of Cagliari, Viale S. Ignazio da Laconi, 9-11, 09123 Cagliari, Italy;
- Centre for the Conservation of Biodiversity (CCB), Life and Environmental Sciences Department, University of Cagliari, Viale S. Ignazio da Laconi 11-13, 09123 Cagliari, Italy
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7
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Carasso V, Mucciarelli M, Dovana F, Müller JV. Comparative Germination Ecology of Two Endemic Rhaponticum Species (Asteraceae) in Different Climatic Zones of the Ligurian and Maritime Alps (Piedmont, Italy). PLANTS 2020; 9:plants9060708. [PMID: 32498314 PMCID: PMC7356568 DOI: 10.3390/plants9060708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/13/2020] [Accepted: 05/30/2020] [Indexed: 11/16/2022]
Abstract
Comparative studies of seed germination of closely related taxa can help increase our understanding of the ecological limitations of cold-adapted plants and forecast how they might respond to global warming. No studies exist on the relationship between thermoclimatic belts that classify mountain life zones according to bioclimatic criteria and the germination strategy of alpine plants. The aim of this study was to assess this relationship using two closely related species growing in different thermotypes and to test whether their germination responses were related to the climate at natural sites. Fresh Rhaponticum bicknellii and R. scariosum seeds were cold stratified for 0, 30, 60 and 90 days and tested for germination at 10, 15 and 20 °C. At the same time, seed burial experiments were run in the field and in the plant nursery. A GLM analysis showed that the length of cold stratification affected significantly only the germination of R. bicknellii seeds, while increasing temperatures prompted germination in both species. We found that R. bicknellii adopts a drought-avoiding germination strategy, while R. scariosum germination is favoured by warm temperatures. Our findings support the general view that alpine plants do not share common germination requirements and that any conclusions should be interpreted from a biogeographical and bioclimatic perspective. Therefore, seed germination and seedling establishment of endemic alpine species can also be predicted by looking at the bioclimate of the species’ range.
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Affiliation(s)
- Valentina Carasso
- Centro Regionale Biodiversità Vegetale, Ente di gestione delle Aree Protette delle Alpi Marittime, Via S. Anna, 34, 12013 Chiusa di Pesio, Italy
- Correspondence: ; Tel.: +39-171-734021
| | - Marco Mucciarelli
- Department of Life Sciences and Systems Biology, Viale P.A. Mattioli, 25, Università di Torino, 10125 Torino, Italy; (M.M.); (F.D.)
| | - Francesco Dovana
- Department of Life Sciences and Systems Biology, Viale P.A. Mattioli, 25, Università di Torino, 10125 Torino, Italy; (M.M.); (F.D.)
| | - Jonas V Müller
- Royal Botanic Gardens Kew, Millennium Seed Bank, Conservation Science, Wakehurst Place, Ardingly, West Sussex RH17 6TN, UK;
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8
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Newton RJ, Hay FR, Ellis RH. Temporal patterns of seed germination in early spring-flowering temperate woodland geophytes are modified by warming. ANNALS OF BOTANY 2020; 125:1013-1023. [PMID: 32055829 PMCID: PMC7262466 DOI: 10.1093/aob/mcaa025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 02/11/2020] [Indexed: 05/27/2023]
Abstract
BACKGROUND AND AIMS Understorey species in temperate deciduous woodlands such as wild daffodil (Narcissus pseudonarcissus) and common snowdrop (Galanthus nivalis) have complex dormancy: seeds that are shed in late spring require warm summer temperatures for embryo elongation and dormancy alleviation, but then cooler temperatures for germination in autumn. As seasons warm and tree canopies alter, how will different seasonal temperature sequences affect these complex dormancy responses? METHODS The effect of different sequences of warmer (+5 °C), current or cooler (-5 °C) seasons (summer to spring) on seed germination patterns over seven successive seasons were investigated, with all sequences combined factorially to determine the consequences of differential seasonal temperature change for the temporal pattern of germination (and so seedling recruitment). KEY RESULTS Little (<1 %, G. nivalis) or no (N. pseudonarcissus) seed germination occurred during the first summer in any treatment. Germination of N. pseudonarcissus in the first autumn was considerable and greatest at the average (15 °C) temperature, irrespective of the preceding summer temperature; germination was also substantial in winter after a warmer autumn. Germination in G. nivalis was greatest in the warmest first autumn and influenced by preceding summer temperature (average > warmer > cooler); the majority of seeds that germinated over the whole study did so during the two autumns but also in year 2's cooler summer after a warm spring. CONCLUSIONS Warmer autumns and winters delay first autumn germination of N. pseudonarcissus to winter but advance it in G. nivalis; overall, warming will deplete the soil seed bank of these species, making annual seed influx increasingly important for recruitment and persistence. This study provides a comprehensive account of the effects of temperature changes in different seasons on seed germination in these early spring-flowering geophytes and consequently informs how these and other temperate woodland species with complex seed dormancy may respond to future climate change.
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Affiliation(s)
- Rosemary J Newton
- Conservation Science Department, Royal Botanic Gardens Kew, Millennium Seed Bank, Wakehurst, Ardingly, West Sussex, UK
- School of Agriculture, Policy and Development, University of Reading, Earley Gate, Reading RG6 6AR, UK
| | - Fiona R Hay
- Conservation Science Department, Royal Botanic Gardens Kew, Millennium Seed Bank, Wakehurst, Ardingly, West Sussex, UK
- Department of Agroecology, Aarhus University, Flakkebjerg, Denmark
| | - Richard H Ellis
- School of Agriculture, Policy and Development, University of Reading, Earley Gate, Reading RG6 6AR, UK
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Catelotti K, Bino G, Offord CA. Thermal germination niches of
Persoonia
species and projected spatiotemporal shifts under a changing climate. DIVERS DISTRIB 2020. [DOI: 10.1111/ddi.13040] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Affiliation(s)
- Katharine Catelotti
- The Australian PlantBank The Royal Botanic Gardens and Domain Trust Sydney NSW Australia
| | - Gilad Bino
- Centre for Ecosystem Science School of Biological, Earth and Environmental Sciences UNSW Australia Sydney NSW Australia
| | - Cathy A. Offord
- The Australian PlantBank The Royal Botanic Gardens and Domain Trust Sydney NSW Australia
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10
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Cochrane A. Temperature thresholds for germination in 20 short-range endemic plant species from a Greenstone Belt in southern Western Australia. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22 Suppl 1:103-112. [PMID: 30556244 DOI: 10.1111/plb.12951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 12/12/2018] [Indexed: 06/09/2023]
Abstract
The study of climate-driven effects on seed traits such as germination has gained momentum over the past decade as the impact of global warming becomes more apparent on the health and survival of plant diversity. Seed response to warming was evaluated in a suite of short-range endemic species from the biodiverse Greenstone Belt of southern Western Australia. The temperature dimensions for germination in 20 woody perennials were identified using small unreplicated samples over 6 weeks on a temperature gradient plate (constant and fluctuating temperatures between 5 and 40 °C). These data were subsequently modelled against current and forecast (2070) mean monthly minimum and maximum temperatures to illustrate seasonal changes to germination timing and final percentage germination. All but one species attained full germination in at least one cell on the gradient plate. Modelling of the data suggested only minimal changes to percentage germination despite a forecast rise in diurnal temperatures over the next 50 years. Nine species were predicted to experience declines of between <1% and 7%, whilst 11 species were predicted to increase their germination by <1% to 3%. Overall, the speed of germination is predicted to increase but the timing of germination for most species shifts seasonally (both advances and delays) as a result of changing diurnal temperatures. The capacity of this suite of species to cope with warmer temperatures during a critical early life stage shows a degree of adaptation to heterogeneous environments. Predicting the effects of global change on terrestrial plant communities is crucial to managing and conserving plant diversity.
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Affiliation(s)
- A Cochrane
- Biodiversity Conservation Science, Department of Biodiversity, Conservation and Attractions, Perth, WA, Australia
- Ecology, Evolution and Genetics, College of Medicine, Biology and Environment, Australian National University, Canberra, ACT, Australia
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11
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Dantas BF, Moura MSB, Pelacani CR, Angelotti F, Taura TA, Oliveira GM, Bispo JS, Matias JR, Silva FFS, Pritchard HW, Seal CE. Rainfall, not soil temperature, will limit the seed germination of dry forest species with climate change. Oecologia 2019; 192:529-541. [PMID: 31863165 DOI: 10.1007/s00442-019-04575-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 12/02/2019] [Indexed: 11/24/2022]
Abstract
Drylands are predicted to become more arid and saline due to increasing global temperature and drought. Although species from the Caatinga, a Brazilian tropical dry forest, are tolerant to these conditions, the capacity for germination to withstand extreme soil temperature and water deficit associated with climate change remains to be quantified. We aimed to evaluate how germination will be affected under future climate change scenarios of limited water and increased temperature. Seeds of three species were germinated at different temperatures and osmotic potentials. Thermal time and hydrotime model parameters were established and thresholds for germination calculated. Germination performance in 2055 was predicted, by combining temperature and osmotic/salt stress thresholds, considering soil temperature and moisture following rainfall events. The most pessimistic climate scenario predicts an increase of 3.9 °C in soil temperature and 30% decrease in rainfall. Under this scenario, soil temperature is never lower than the minimum and seldomly higher than maximum temperature thresholds for germination. As long as the soil moisture (0.139 cm3 cm3) requirements are met, germination can be achieved in 1 day. According to the base water potential and soil characteristics, the minimum weekly rainfall for germination is estimated to be 17.5 mm. Currently, the required minimum rainfall occurs in 14 weeks of the year but will be reduced to 4 weeks by 2055. This may not be sufficient for seedling recruitment of some species in the natural environment. Thus, in future climate scenarios, rainfall rather than temperature will be extremely limiting for seed germination.
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Affiliation(s)
- Barbara F Dantas
- Embrapa Semiárido, Caixa Postal 23, Rodovia BR-428, Km 152, Zona Rural, Petrolina, 56302-970, PE, Brazil.
| | - Magna S B Moura
- Embrapa Semiárido, Caixa Postal 23, Rodovia BR-428, Km 152, Zona Rural, Petrolina, 56302-970, PE, Brazil
| | | | - Francislene Angelotti
- Embrapa Semiárido, Caixa Postal 23, Rodovia BR-428, Km 152, Zona Rural, Petrolina, 56302-970, PE, Brazil
| | - Tatiana A Taura
- Embrapa Semiárido, Caixa Postal 23, Rodovia BR-428, Km 152, Zona Rural, Petrolina, 56302-970, PE, Brazil
| | - Gilmara M Oliveira
- Universidade Estadual de Feira de Santana- UEFS, Feira de Santana, BA, Brazil
| | | | - Janete R Matias
- Universidade Federal Rural do Semiárido- UFERSA, Mossoró, RN, Brazil
| | - Fabricio F S Silva
- Universidade Estadual de Feira de Santana- UEFS, Feira de Santana, BA, Brazil
| | - Hugh W Pritchard
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, UK
| | - Charlotte E Seal
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, UK
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Fernández-Pascual E, Mattana E, Pritchard HW. Seeds of future past: climate change and the thermal memory of plant reproductive traits. Biol Rev Camb Philos Soc 2018; 94:439-456. [PMID: 30188004 DOI: 10.1111/brv.12461] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 07/30/2018] [Accepted: 08/02/2018] [Indexed: 01/21/2023]
Abstract
Plant persistence and migration in face of climate change depends on successful reproduction by seed, a central aspect of plant life that drives population dynamics, community assembly and species distributions. Plant reproduction by seed is a chain of physiological processes, the rates of which are a function of temperature, and can be modelled using thermal time models. Importantly, while seed reproduction responds to its instantaneous thermal environment, there is also evidence of phenotypic plasticity in response to the thermal history experienced by the plant's recent ancestors, by the reproducing plant since seedling establishment, and by its seeds both before and after their release. This phenotypic plasticity enables a thermal memory of plant reproduction, which allows individuals to acclimatise to their surroundings. This review synthesises current knowledge on the thermal memory of plant reproduction by seed, and highlights its importance for modelling approaches based on physiological thermal time. We performed a comprehensive search in the Web of Science and analysed 533 relevant articles, of which 81 provided material for a meta-analysis of thermal memory in reproductive functional traits based on the effect size Zr. The articles encompassed the topics of seed development, seed yield (mass and number), seed dormancy (physiological, morphological and physical), germination, and seedling establishment. The results of the meta-analysis provide evidence for a thermal memory of seed yield, physiological dormancy and germination. Seed mass and physiological dormancy appear to be the central hubs of this memory. We argue for integrating thermal memory into a predictive framework based on physiological time modelling. This will provide a quantitative assessment of plant reproduction, a complex system that integrates past and present thermal inputs to achieve successful reproduction in changing environments. The effects of a warming environment on plant reproduction cannot be reduced to a qualitative interpretation of absolute positives and negatives. Rather, these effects need to be understood in terms of changing rates and thresholds for the physiological process that underlie reproduction by seed.
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Affiliation(s)
- Eduardo Fernández-Pascual
- Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew; Wellcome Trust Millennium Building, Wakehurst Place, Ardingly, West Sussex, RH17 6TN, U.K.,Departamento de Biología de Organismos y Sistemas, Universidad de Oviedo; C/ Catedrático Rodrigo Uría, 33006, Oviedo/Uviéu, Spain
| | - Efisio Mattana
- Natural Capital and Plant Health, Royal Botanic Gardens, Kew; Wellcome Trust Millennium Building, Wakehurst Place, Ardingly, West Sussex, RH17 6TN, U.K
| | - Hugh W Pritchard
- Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew; Wellcome Trust Millennium Building, Wakehurst Place, Ardingly, West Sussex, RH17 6TN, U.K
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Seal CE, Daws MI, Flores J, Ortega-Baes P, Galíndez G, León-Lobos P, Sandoval A, Ceroni Stuva A, Ramírez Bullón N, Dávila-Aranda P, Ordoñez-Salanueva CA, Yáñez-Espinosa L, Ulian T, Amosso C, Zubani L, Torres Bilbao A, Pritchard HW. Thermal buffering capacity of the germination phenotype across the environmental envelope of the Cactaceae. GLOBAL CHANGE BIOLOGY 2017; 23:5309-5317. [PMID: 28657127 DOI: 10.1111/gcb.13796] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 06/12/2017] [Accepted: 06/19/2017] [Indexed: 06/07/2023]
Abstract
Recruitment from seeds is among the most vulnerable stage for plants as global temperatures change. While germination is the means by which the vast majority of the world's flora regenerate naturally, a framework for accurately predicting which species are at greatest risk of germination failure during environmental perturbation is lacking. Taking a physiological approach, we assess how one family, the Cactaceae, may respond to global temperature change based on the thermal buffering capacity of the germination phenotype. We selected 55 cactus species from the Americas, all geo-referenced seed collections, reflecting the broad environmental envelope of the family across 70° of latitude and 3700 m of altitude. We then generated empirical data of the thermal germination response from which we estimated the minimum (Tb ), optimum (To ) and ceiling (Tc ) temperature for germination and the thermal time (θ50 ) for each species based on the linearity of germination rate with temperature. Species with the highest Tb and lowest Tc germinated fastest, and the interspecific sensitivity of the germination rate to temperature, as assessed through θ50 , varied tenfold. A left-skewed asymmetry in the germination rate with temperature was relatively common but the unimodal pattern typical of crop species failed for nearly half of the species due to insensitivity to temperature change at To . For 32 fully characterized species, seed thermal parameters correlated strongly with the mean temperature of the wettest quarter of the seed collection sites. By projecting the mean temperature of the wettest quarter under two climate change scenarios, we predict under the least conservative scenario (+3.7°C) that 25% of cactus species will have reduced germination performance, whilst the remainder will have an efficiency gain, by the end of the 21st century.
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Affiliation(s)
- Charlotte E Seal
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Ardingly, UK
| | - Matthew I Daws
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Ardingly, UK
| | - Joel Flores
- División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, San Luis Potosí, México
| | - Pablo Ortega-Baes
- Laboratorio de Investigaciones Botánicas (LABIBO)-CONICET, Facultad de Ciencias Naturales, Universidad Nacional de Salta, Salta, Argentina
| | | | - Pedro León-Lobos
- Banco Base de Semillas, Instituto de Investigaciones Agropecuarias, INIA, Vicuña, Chile
| | - Ana Sandoval
- Banco Base de Semillas, Instituto de Investigaciones Agropecuarias, INIA, Vicuña, Chile
| | - Aldo Ceroni Stuva
- Jardín Botánico "Octavio Velarde Núñez", Universidad Nacional Agraria La Molina, Lima, Perú
| | - Natali Ramírez Bullón
- Jardín Botánico "Octavio Velarde Núñez", Universidad Nacional Agraria La Molina, Lima, Perú
| | - Patricia Dávila-Aranda
- Facultad de Estudios Superiores-Iztacala, Universidad Nacional Autónoma de México, Thalnepantla, México
| | - Cesar A Ordoñez-Salanueva
- Facultad de Estudios Superiores-Iztacala, Universidad Nacional Autónoma de México, Thalnepantla, México
| | - Laura Yáñez-Espinosa
- Instituto de Investigación de Zonas Desérticas, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
| | - Tiziana Ulian
- Department of Natural Capital & Plant Health, Royal Botanic Gardens, Kew, Ardingly, UK
| | - Cecilia Amosso
- Dipartimento di Scienze della Terra e dell' Ambiente, Università degli Studi di Pavia, Pavia, Italy
| | - Lino Zubani
- Dipartimento di Scienze della Terra e dell' Ambiente, Università degli Studi di Pavia, Pavia, Italy
| | - Alberto Torres Bilbao
- Empresa Nacional para la Protección de la Flora y la Fauna, Banda Placetas, Santa Clara, Cuba
| | - Hugh W Pritchard
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Ardingly, UK
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Galíndez G, Seal CE, Daws MI, Lindow L, Ortega-Baes P, Pritchard HW. Alternating temperature combined with darkness resets base temperature for germination (T b ) in photoblastic seeds of Lippia and Aloysia (Verbenaceae). PLANT BIOLOGY (STUTTGART, GERMANY) 2017; 19:41-45. [PMID: 26998824 DOI: 10.1111/plb.12449] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/14/2016] [Indexed: 06/05/2023]
Abstract
Thermal time models for seed germination assume a continuum of rate responses in the sub-optimal temperature range. Generally, the models describe germination performance in non-dormant seeds at constant temperatures, yet alternating temperature (AT) is a feature of many natural environments. We studied the possible interacting effects of AT on germination progress in photoblastic seeds of three aromatic-medicinal Verbenaceae species in the genera Lippia and Aloysia. For Lippia turbinata f. turbinata and L. turbinata f. magnifolia seed, germination only occurred in light conditions, while for L. integrifolia and Aloysia citriodora it was significantly higher in the light than in darkness. Although relative light germination (RLG) was not different between constant and AT in the sub-optimal range, AT raised the base temperature for germination progress (Tb ) from ca. 3-6 °C in constant temperature to 7-12 °C in AT. Among the species, thermal time for 50% seed germination [θT(50) ] was 55-100 °Cd at constant temperature. Although AT resulted in slight modifications to θT(50) , the germination rate at comparable average temperatures in the sub-optimal range was slower than under constant temperatures. For all species, the proportion of germinated seeds was similar for constant and AT. Our results suggest that an interaction between cool temperature and darkness during AT treatment limits the temperature range permissive for germination in these positively photoblastic seed, reflecting both close adaptation to the natural ecology and niche requirements of the species.
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Affiliation(s)
- G Galíndez
- Laboratorio de Investigaciones Botánicas (LABIBO)-CONICET, Facultad de Ciencias Naturales, Universidad Nacional de Salta, Salta, Argentina
| | - C E Seal
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Ardingly, UK
| | - M I Daws
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Ardingly, UK
| | - L Lindow
- Laboratorio de Investigaciones Botánicas (LABIBO)-CONICET, Facultad de Ciencias Naturales, Universidad Nacional de Salta, Salta, Argentina
| | - P Ortega-Baes
- Laboratorio de Investigaciones Botánicas (LABIBO)-CONICET, Facultad de Ciencias Naturales, Universidad Nacional de Salta, Salta, Argentina
| | - H W Pritchard
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Ardingly, UK
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Burghardt LT, Edwards BR, Donohue K. Multiple paths to similar germination behavior in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2016; 209:1301-12. [PMID: 26452074 DOI: 10.1111/nph.13685] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 08/24/2015] [Indexed: 05/25/2023]
Abstract
Germination timing influences plant fitness, and its sensitivity to temperature may cause it to change as climate shifts. These changes are likely to be complex because temperatures that occur during seed maturation and temperatures that occur post-dispersal interact to define germination timing. We used the model organism Arabidopsis thaliana to determine how flowering time (which defines seed-maturation temperature) and post-dispersal temperature influence germination and the expression of genetic variation for germination. Germination responses to temperature (germination envelopes) changed as seeds aged, or after-ripened, and these germination trajectories depended on seed-maturation temperature and genotype. Different combinations of genotype, seed-maturation temperature, and after-ripening produced similar germination envelopes. Likewise, different genotypes and seed-maturation temperatures combined to produce similar germination trajectories. Differences between genotypes were most likely to be observed at high and low germination temperatures. The germination behavior of some genotypes responds weakly to maternal temperature but others are highly plastic. We hypothesize that weak dormancy induction could synchronize germination of seeds dispersed at different times. By contrast, we hypothesize that strongly responsive genotypes may spread offspring germination over several possible germination windows. Considering germination responses to temperature is important for predicting phenology expression and evolution in future climates.
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Affiliation(s)
- Liana T Burghardt
- Department of Biology, Duke University, Durham, NC, 27708, USA
- Department of Plant Biology, University of Minnesota, St Paul, MN, 55108, USA
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