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Societal Impact Statement: Conservation seed banks maintain collections of many seed‐bearing plant species, providing germplasm and data to support management of wild populations. However, a proportion of plant species produce seeds that are difficult to collect, dry, store and utilise; these are known as 'exceptional' species. Here we tested a framework for identifying exceptional species, to document examples and provide case studies within the Australian flora. We present a workflow that may be used to identify additional exceptional species, and direct efforts to establish appropriate collection types (seeds and/or living collections, tissue culture or cryopreservation) for their ex situ conservation. Summary: Seed banking is well established to contribute to the conservation of many seed‐bearing plant species ex situ for future use in restoration, translocation, agriculture and horticulture. In Australia, over 67% of currently listed threatened plants are represented in conservation seed banks. However, there are challenges to conserving the full extent of plant diversity in seed banks, with growing recognition that we need to think beyond conventional seed banking methods to conserve 'exceptional' plant species that are difficult to collect, store and germinate. We examine how the framework for identification of such species can be applied to the Australian flora, using examples from the recently published guidelines for 'Plant Germplasm Conservation in Australia' and case studies and data arising from the Australian Academy of Science Fenner Conference on the Environment 'Exceptional Times, Exceptional Plants'. We present a workflow to assist conservation decision‐makers and practitioners in identifying exceptional species and overcoming barriers to storage of germplasm, enabling appropriate ex situ collection types to be established via seeds, living collections, tissue culture, cryopreservation or a combination of these. Australia's seed conservation sector continues to expand, with increasing expertise, facilities and networks established to conserve a diversity of plant species; however, resolving the challenges relating to each exceptionality factor requires significantly more time, labour and collaboration than current capacity allows. Understanding the barriers to conservation and production of healthy plants, via germination or other methods of propagation, is a critical component of conserving species long‐term and ultimately returning plants to the landscape. [ABSTRACT FROM AUTHOR]

Keywords: data synthesis; database; germination; open science; plant reproduction; repository; seed; trait EN data synthesis database germination open science plant reproduction repository seed trait 466 470 5 09/25/23 20231015 NES 231015 Data availability The data and code used to produce this article are available at https://github.com/efernandezpascual/seedarcms. The need for a global archive of primary seed germination data The seed ecology community has recently recognized the need to synthesize knowledge, setting the research agenda for functional seed ecology (Saatkamp I et al i ., [34]). I SeedArc i compiles primary seed germination data to synthesize the seed germination spectrum at a global scale. The theory underlying the seed germination spectrum has been laid out by decades of work on seed ecology (Baskin & Baskin, [1]), but empirical studies testing major ecological hypotheses at both global and local scales remain elusive without a standardized seed germination database. [Extracted from the article]

Summary: Critically endangered grasslands and grassy woodlands were once widespread across south‐eastern Australia. However, more than 200 years of European land use means less than 1% of their pre‐European extent remains today. Conservation and restoration of these ecosystems involves reintroducing fire to periodically reduce competition and allow smaller species to establish. Furthermore, seeds of native species are sown – but often fail to establish as many forbs and grasses are hard‐to‐germinate. Therefore, data on how these species respond to fire‐related germination cues, such as smoke and heat, can benefit our understanding of both how species respond to fire and identify treatments which can be used to increase germination. We conducted a germination trial to determine if smoke and heat cues increase percent germination and germination speed of 55 common grassy ecosystem species. Fire cues increased germination speed and/or percent germination of 44 of the 55 study species. These results have three implications for grassy ecosystem conservation and restoration: (i) fire may aid conservation by maximizing germination of native species; (ii) pre‐treating seed with smoke and/or heat prior to sowing may increase germination when restoring these ecosystems via direct seeding; and (iii) smoke and heat can be used to increase germination when growing seedlings for plantings. [ABSTRACT FROM AUTHOR]

Fire increases seedling recruitment by reducing competition for space and resources. As such, many species in fire‐prone ecosystems germinate in response to fire cues such as smoke and heat. A notable exception is fire‐prone temperate grassy ecosystems, where >20 yr of research has found that fire‐cued germination is rare. We tested the hypothesis that fire cues promote germination in temperate grassy ecosystems of south‐eastern Australia. We treated seeds of 55 common species with smoke, heat, and a combination of smoke and heat and tracked germination over time. We analyzed the effect of all combinations of treatments on germination speed and percent germination. Interestingly, we found that smoke and heat combined—which is more ecologically relevant to an actual fire than smoke and heat alone—was needed to increase germination speed, a mostly unstudied component of the germination ecology of grassy ecosystems. Smoke alone increased percent germination. Both plant family and seed traits influenced the germination response to smoke and heat. Poaceae species were the most responsive (in both speed and percent germination) to smoke alone. Water permeability of the seed coat was a key determinant of whether species responded to heat alone, smoke alone, or combined smoke and heat. Species with water‐impermeable seed coats responded to heat alone for both speed and percent germination. Species with water‐permeable seed coats germinated faster in response to combined smoke and heat and percent germination was increased by smoke alone. In contrast with more than two decades of research—our study of this large and representative group of species demonstrates that fire (via smoke and heat) is an important germination cue in fire‐prone temperate grassy ecosystems of south‐eastern Australia. [ABSTRACT FROM AUTHOR]

Summary: 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. [ABSTRACT FROM AUTHOR]

In grassy ecosystems of south‐eastern Australia, fire maintains richness of native forbs. It is commonly thought that fire promotes regeneration indirectly by reducing competition for light and providing gaps for recruitment, rather than directly stimulating germination. However, physiological dormancy and morphophysiological dormancy are common, and few studies have explored responses to fire‐cues among dormant or hard‐to‐germinate forbs. Recent studies from other fire‐prone ecosystems suggest that in some cases, fire‐cues may not alleviate physiological or morphophysiological dormancy, but instead promote germination in combination with treatments which alleviate dormancy. We experimentally tested the prevailing hypothesis that perennial forbs common in south‐eastern Australian grassy ecosystems do not germinate in direct response to fire. Responses to fire‐cues both inherently and in combination with treatments which alleviate dormancy were investigated for seven species. Two fire‐cues (smoke and heat) plus a treatment of both heat + smoke were applied to fresh seed at three temperatures (35/25°C, 30/20°C and 25/15°C). Following this, the effect of fire‐cues on seed that had undergone warm stratification, cold stratification and dry‐after‐ripening was investigated. Three species — Arthropodium strictum, Cheiranthera cyanea and Dianella revoluta — responded to fire‐cues inherently, although germination in C. cyanea was low. High germination of D. revoluta was found when fire‐cues were combined with warm stratification. Fire‐cues had no effect on germination of Brunonia australis, Burchardia umbellata and Eryngium ovinum. Germination of Stypandra glauca was zero following all treatment combinations. Our finding that fire‐cues promote germination of three of the seven study species did not provide sufficient evidence to reject the current hypothesis that germination of perennial forbs is not typically promoted by fire‐cues. However, this study highlights the important direct role fire‐cues can play in promoting germination of some perennial forbs both inherently and in combination with treatments used to alleviate physiological dormancy. [ABSTRACT FROM AUTHOR]

Summary: Trait‐based approaches have improved our understanding of plant evolution, community assembly and ecosystem functioning. A major challenge for the upcoming decades is to understand the functions and evolution of early life‐history traits, across levels of organization and ecological strategies. Although a variety of seed traits are critical for dispersal, persistence, germination timing and seedling establishment, only seed mass has been considered systematically. Here we suggest broadening the range of morphological, physiological and biochemical seed traits to add new understanding on plant niches, population dynamics and community assembly. The diversity of seed traits and functions provides an important challenge that will require international collaboration in three areas of research. First, we present a conceptual framework for a seed ecological spectrum that builds upon current understanding of plant niches. We then lay the foundation for a seed‐trait functional network, the establishment of which will underpin and facilitate trait‐based inferences. Finally, we anticipate novel insights and challenges associated with incorporating diverse seed traits into predictive evolutionary ecology, community ecology and applied ecology. If the community invests in standardized seed‐trait collection and the implementation of rigorous databases, major strides can be made at this exciting frontier of functional ecology. [ABSTRACT FROM AUTHOR]

It has been almost 15 years since concerns about the limited capacity of remnant native vegetation to supply the volumes of seed required to meet increasing restoration demands were first raised. Since that time little progress has been made towards addressing this constraint with the ongoing decline of native vegetation communities, especially since 2000, further challenging seed supply. We provide examples of the size of this demand for seed, as well as major issues associated with seed sourcing. We also discuss how invoking the concept of market forces to drive seed supply and demand is inappropriate and highlight the need for an industry body to oversee seed collection and utilisation standards. We further propose key actions that are required to secure the seed supply chain within the next 20 years to meet existing and future restoration targets. We argue that concerted, coordinated action at Commonwealth, State and regional levels are required to underpin effective future restoration outcomes. [ABSTRACT FROM AUTHOR]

Species' movements affect their response to environmental change but movement knowledge is often highly uncertain. We now have well‐established methods to integrate movement knowledge into conservation practice but still lack a framework to deal with uncertainty in movement knowledge for environmental decisions. We provide a framework that distinguishes two dimensions of species' movement that are heavily influenced by uncertainty: knowledge about movement and relevance of movement to environmental decisions. Management decisions can be informed by their position in this knowledge‐relevance space. We then outline a framework to support decisions around (1) increasing understanding of the relevance of movement knowledge, (2) increasing robustness of decisions to uncertainties and (3) improving knowledge on species' movement. Our decision‐support framework provides guidance for managing movement‐related uncertainty in systematic conservation planning, agri‐environment schemes, habitat restoration and international biodiversity policy. It caters to different resource levels (time and funding) so that species' movement knowledge can be more effectively integrated into environmental decisions. [ABSTRACT FROM AUTHOR]