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We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.

Zieria buxijugum , Z. formosa , and Z. parrisiae are three closely related, Critically Endangered species of questionable taxonomic validity that occur within six kilometres of each other on the south coast of New South Wales, Australia. We investigated genetic relationships and diversity of these species, along with two related but taxonomically distinct congeners, Z. granulata and Z. tuberculata , and a possible undescribed taxon, Z. aff. tuberculata. Double-digest restriction-site associated sequencing (ddRADseq) was used to generate anonymous genomic loci that were used for phylogenetic, network, and genetic structure analyses, and for estimating genetic diversity of the threatened species. Our results support the current taxonomic status of Z. buxijugum , Z. formosa , and Z. parrisiae , and suggest that Z. aff. tuberculata warrants recognition as a distinct species. We detected no evidence of inbreeding in the three Critically Endangered species, and found their genetic diversity to be similar to that of the more widespread species Z. granulata and Z. tuberculata. Comparison of plant material held in ex situ collections at the Australian National Botanic Gardens with wild plants highlighted several genotypes of the Critically Endangered species that are not represented in the ex situ collection, and we provide suggestions for the future inclusion of those unrepresented genotypes. [ABSTRACT FROM AUTHOR]

Traits with intuitive names, a clear scope and explicit description are essential for all trait databases. The lack of unified, comprehensive, and machine-readable plant trait definitions limits the utility of trait databases, including reanalysis of data from a single database, or analyses that integrate data across multiple databases. Both can only occur if researchers are confident the trait concepts are consistent within and across sources. Here we describe the AusTraits Plant Dictionary (APD), a new data source of terms that extends the trait definitions included in a recent trait database, AusTraits. The development process of the APD included three steps: review and formalisation of the scope of each trait and the accompanying trait description; addition of trait metadata; and publication in both human and machine-readable forms. Trait definitions include keywords, references, and links to related trait concepts in other databases, enabling integration of AusTraits with other sources. The APD will both improve the usability of AusTraits and foster the integration of trait data across global and regional plant trait databases. [ABSTRACT FROM AUTHOR]

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]

Context. The Cumberland Plain Woodland (CPW) is a threatened ecological community that is expected to experience heatwaves of increasing intensity and frequency into the future. Given the central role that temperature plays in regulating seed germination, understanding the impacts of such heatwaves on key germination attributes is vital to identify potential impacts on plant community structure. Aims. To determine the impacts of increased heatwave intensity and frequency treatments on seed germination within and across 15 native species of the CPW. We also examined the influence of interspecific variation in life-history traits on germination responses. Methods. Seeds were exposed to seven heatwave treatments of increasing intensity and frequency. Life-history trait data were also collected for each species' dormancy type, fire response traits, life form and seed mass. Key results. There was evidence within the study species of a significant effect of heatwave treatment. Germination duration was prolonged for the two most extreme simulated heatwave events. Life-history traits could not explain germination responses after heatwave treatments, however, larger seeded species had quicker germination onset and shorter periods of germination over small-seeded species; and trees had lower proportions of germination than any other life form. Conclusions. Increases in heatwave intensity and frequency have an impact on seed germination responses in native species of the CPW. Life-history traits could not explain germination responses across species along the heatwave gradient. Implications. Projected increases in heatwave intensity and frequency are likely to impact seed germination, and thus community composition, in species from the CPW. [ABSTRACT FROM AUTHOR]

The crises of biodiversity loss, climate change and food security are challenges faced by the conservation and agriculture sectors.We outline, via presentations from the Australasian Seed Science Conference, how seed science is addressing these challenges. Research is focused on practical solutions for seed bank management, seed use and biodiversity conservation. Emerging trends include understanding the role of seed microbiota on plant performance and the roles of seeds in society and culture. [ABSTRACT FROM AUTHOR]

Context. Seeding is common practice for ecological restoration, but establishment rates can be low. For seeds to successfully establish they must transition through early life stages of germination, emergence, and (initial) survival. Examining these demographic processes for seeds sown under a range of abiotic conditions can identify failure points and inform techniques to improve seed use. Aims. Here we quantified seed and seedling life-stage transitions in five reconstructed soils across four varying levels of simulated rainfall using five species (Acacia hilliana, Acacia inaequilatera, Indigofera monophylla, Triodia pungens, and Triodia wiseana) commonly seeded for mined land restoration of the Pilbara bioregion in north-west Western Australia. Methods. Germination, emergence, and survival were measured over a 6 week period and transition probabilities between each life-stage transition were modelled for each treatment combination. Key results. For four species, both rainfall amount and/or soil substrate significantly influenced germination probability. Rainfall was the more significant determinant, with germination greatest under the higher rainfall regimes of 120-280 mm, irrespective of soil type. Following germination, emergence of both Acacia spp. was positively influenced by soils containing topsoil, suggesting the microenvironment of soils containing topsoil was most favourable during this emergence phase. The effect of substrate was less clearcut for I. monophylla and Triodia spp, where emergence was most limited in substrates comprised solely of overburden waste material and the lowest rainfall regime exacerbated emergence failure, relative to germination success. When compared to the well-watered, 100% topsoil substrate, seedling survival of all species was most constrained in the 100% overburden waste, demonstrating these reconstructed mining substrates compromise seedling recruitment. Conclusions. This study underscores that successful seedling recruitment in this ecosystem is dependent on frequent, and repeated, rainfall events above a certain threshold (≥120 mm) and highlights the beneficial effects of sowing seeds in a substrate containing topsoil. Implications. Future seeding technologies should focus on improving the moisture relations of the microsite to offset the recruitment challenges experienced by seeds sown in hostile growing environments such as the overburden wastes tested here. [ABSTRACT FROM AUTHOR]

Context. Australia's tropical montane cloud forests (TMCF) exhibit exceptional species richness and endemism. Determinants of regeneration via seed of these species are next to unknown, limiting our ability to quantify and project their vulnerability to climate change. The ratio of red to far-red light (R:FR) has been shown to influence seed germination of many tropical species. Aims. We investigated germination of six previously unstudied TMCF species in relation to the presence or absence of light (light/dark) and light quality (R:FR). We hypothesised that increased R:FR would lead to increased germination and that small-seeded species would be more likely to have a light requirement and be less sensitive to R:FR compared to larger-seeded species. Methods. Sunlight and polyester filters were used to create a gradient of R:FR ranging from0.1 to 1.14. Seeds were also sown in constant darkness. Key results. Across species we saw varying germination responses. Three of the four smallest-seeded species exhibited an absolute light requirement for germination and did not discriminate between different R:FR. Germination of the small-seeded TMCF endemic Dracophyllum increased exponentially with increasing R:FR. Germination of the largest-seeded species was inhibited by both low and high R:FR, and germination was higher in constant darkness than diurnal light/dark. All six species were able to germinate at remarkably low R:FR values. Conclusions. Light affects seed germination of Australia's TMCF plant species in a variety of ways. Implications. The findings of this study provide insights into plant recruitment in situ, and the acclimation potential of these species under reduced R:FR predicted for the future. [ABSTRACT FROM AUTHOR]

Context. Seeds harbour a diversity of microbes, which in some plants aid with germination and establishment. Seeds form a critical part in the lifecycle of plants and a role in many conservation and restoration activities. Aims. Because this is an emerging field in seed biology, we aim to highlight the key research gaps of interest to seed on the basis of restoration and ex situ conservation. Methods. We identify knowledge gaps associated with the seed endophytic microbiome of native Australian plants through undertaking a literature review. Additionally, culturing methods were used to identify the fungal seed endophytes of five native Australian species. Key results. We identified a diversity of taxa within the native seed and show three taxa that are common to all study hosts. Sampling seed from additional hosts at a site and additional sites of a host species showed new fungal diversity. Our literature review showed that little information is available on native seed microbiomes and we identified four key areas where research gaps exist, linking with seed-based restoration practices. Conclusions. We provide evidence that there is a complex and diverse seed microbiome within some Australian native plants and suggest ways that it could be integrated into restoration and conservation practices. Implications. We propose that by taking into consideration the presence of a seed microbiome and its potential impacts on plant health, seed microbiomes could be used as one method to restore microbial diversity into an ecosystem and to contribute to the seedling microbiome and plant health at restored sites. [ABSTRACT FROM AUTHOR]

Context. Fifty per cent of Australian rainforest species produce orthodox seeds, but little is known about their longevity in storage. Aims. To (1) estimate the longevity of seeds of 33 rainforest species using artificial aging; (2) assess the influence of habit, habitat range (restricted to rainforest or more broadly distributed), seed characteristics (endospermy, dry weight), and collection environment (e.g. precipitation, elevation and average temperature) on longevity; (3) compare longevity of rainforest seeds to previously assessed species from non-rainforest habitats; (4) compare longevity in artificial aging to real-time longevity in storage. Methods. Seeds were aged at 60% relative humidity and 45°C, and tested at pre-determined intervals until germination was reduced to zero. The time taken for germination to decline to 50% (p50AA) was calculated by probit analysis. Ordinary least-squares regression was used to model p50AA for rainforest and non-rainforest species against predictor variables. Values for p50AA were then compared with the actual longevity in storage at -20°C (p50RT) using Pearson's correlation. Key results. Species restricted to rainforest exhibited a significantly lower p50AA than species with a wider distribution or those restricted to non-rainforest habitats. Collection elevation had a significant negative influence on p50AA. In all, 14 of 33 species showed a significant decline in viability after ≤12 years in storage. Values of p50AA were not correlated with p50RT. Conclusions. Rainforests contain a high proportion of potentially, and actually, short-lived species; however, p50AA is not a good predictor of their real-time longevity. Implications. Rainforest species should be managed as short-lived, with viability checked at least every 5 years, until real-time longevity data indicate otherwise. [ABSTRACT FROM AUTHOR]

Seed science is a vital field of research that contributes to many areas of knowledge in fundamental ecology and evolution, as well as in applied areas of food production, and the conservation and restoration of native plants. A large amount of novel information, technologies and processes in seed science research are being produced and developed by early to middle career researchers (EMCRs) in academic, government and private science sectors. This breadth and novelty of research by EMCRs was evident at the second Australasian Seed Science Conference held online in September 2021. EMCRs represented almost one-third of the presenting delegates at the conference and covered research in areas including functional seed trait relationships, responses of seed traits and germination to environmental change, managing seeds in ex-situ seed and germplasm collections and using seeds as food sources. As future environmental, social and economic challenges arise, EMCR seed scientists will be at the forefront of emerging fundamental ecological and evolutionary seed science knowledge, as well as the development of technologies and processes for the conservation of native species, the utilisation of seeds in agriculture and food production, and many new ideas yet to be discovered. [ABSTRACT FROM AUTHOR]

The article discusses the ex situ conservation breakthrough at the Australian National Botanic Gardens, highlighting the successful acquisition of viable seeds for the highly exceptional species, the Endangered Muehlenbeckia tuggeranong, through a combination of living collections and seed biology research. This achievement has opened up various research avenues to further support the conservation of this unique species.

Context: Seed dormancy is one issue hindering implementation of conservation actions for rainforest species. Aims: We studied dormancy and germination in Tasmannia sp. Mt Bellenden Ker and Tasmannia membranea , two tropical montane rainforest species threatened by climate change, to develop a better understanding of dormancy in the species and the genus. Methods: Dormancy was classified for T. sp. Mt Bellenden Ker on the basis of an imbibition test, analysis of embryo to seed length (E:S) ratios and germination in response to the following four dormancy-breaking treatments: (1) scarification of the seedcoat near the micropylar end; (2) removal of the seedcoat; (3) application of 100 mg L−1 or (4) 500 mg L−1 gibberellic acid. The most effective treatment was then tested on T. membranea. The requirement for light for germination was also assessed. Key results: Both scarified and intact seeds imbibed water. Initial E:S ratios were <0.22 for both species and increased up to 0.74 after 40 days, just before radicle emergence, for T. sp. Mt Bellenden Ker. Germination proportions were significantly higher in Treatments 1 and 2 than the remaining treatments for T. sp. Mt Bellenden Ker; T. membranea responded similarly well to Treatment 1. Germination under alternating light/dark conditions was slightly, but not significantly, greater than germination in the dark alone. Conclusions: Both species have morphophysiological dormancy and treatments that remove seedcoat resistance to embryo growth facilitate germination. These treatments may improve germination in other species from the genus Tasmannia. Implications: This knowledge will aid the germination of seeds to implement conservation strategies for Tasmannia spp. This study investigates seed dormancy and germination in the genus Tasmannia. Two Australian species endemic to tropical rainforest, namely T. sp. Mt Bellenden Ker and T. membranea , were used as representatives of the genus. The distribution of T. sp. Mt Bellenden Ker is restricted to tropical montane cloud forests in far-northern Queensland (FNQ). This habitat is highly susceptible to climate change; therefore, studies that contribute to implementing conservation strategies are essential to preserving its unique flora. [ABSTRACT FROM AUTHOR]

Ploidy and species range size or threat status have been linked to variation in phenotypic and phenological seed and seedling traits, including seed size, germination rate (speed) and seedling stature. There is surprisingly little known about the ecological outcomes of relationships between ploidy, key plant traits and the drivers of range size. Here we determined whether ploidy and range size in Pomaderris , a genus of shrubs that includes many threatened species, are associated with variation in seed and seedling traits that might limit the regeneration performance of obligate seeders in fire-prone systems. We experimentally quantified seed dormancy and germination processes using fire-related heat treatments and evaluated seedling performance under drought stress. We also examined the association of seed size with other seed and seedling traits. Polyploids had bigger seeds, a faster germination rate and larger and taller seedlings than diploids. There was a lack of any clear relationship between range size and seed or seedling traits. The ploidy effects observed for many traits are likely to be indirect and associated with the underlying seed size differences. These findings indicate that there is a higher potential competitive advantage in polyploid than diploid Pomaderris during regeneration, a critical stage in the post-fire environment. This insight to the regeneration phase may need to be considered when planning and prioritising management of threatened species. [ABSTRACT FROM AUTHOR]

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]

The article explores international meeting followed on from the National Seed Science Forum of 2016 and presented the latest advances in seed science across the conservation and agricultural sectors. . it discusses that The Authors would also like to acknowledge the ASSC 2021 Scientific and Organising Committees for their efforts to synthesise the vast amount of information presented throughout the various conference sessions.

Global warming is affecting plant phenology, growth and reproduction in complex ways and is particularly apparent in vulnerable alpine environments. Warming affects reproductive and vegetative traits, as well as phenology, but seldom do studies assess these traits in concert and across the whole of a plant's life cycle, particularly in wild species. Thus, it is difficult to extrapolate from such effects to predictions about the persistence of species or their conservation and management. We assessed trait variation in response to warming in Oreomyrrhis eriopoda , an Australian native montane herb, in which populations vary in germination strategy (degree of dormancy) and growth characteristics as a function of ecological factors. Warming accelerated growth in the early stages of development, particularly for populations with non-dormant seed. The differences in growth disappeared at the transition to reproduction, when an accelerating effect on phenology emerged, to varying degrees depending on germination strategy. Overall, warming reduced flower and seed production and increased mortality, indicating a reduction in reproductive opportunities, particularly for populations with dormant seed. Developmental condition affected germination strategy of the next generation seed, leading to increased degree of dormancy and slowed germination rate. But there were no whole-scale shifts in strategy or total germination percent. Following through the life cycle reveals that warming will have some potentially positive effects (early growth rates) and some negative effects (reduced reproductive output). Ultimately, warming impacts will depend on how those effects play out in the field: early establishment and an accelerated trajectory to seed maturity may offset the tradeoff with overall seed production. Small differences among germination strategies likewise may cascade to larger effects, with important implications for persistence of species in the alpine landscape. Thus, to understand and manage the response of wild species to warming takes a whole-of-life perspective and attention to ecologically significant patterns of within-species variation. [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]

Disturbance has been considered essential for maintaining biodiversity in temperate grassy ecosystems in Australia. This has been particularly well demonstrated for inter-tussock plant species in C4 Themeda -dominated grasslands in mesic environments. Disturbance is also thought crucial to maintain the structure of preferred habitat for some animals. Relationships between disturbance and diversity may be contingent on ecosystem productivity, but little is known about the generality of the disturbance-promoting-diversity paradigm across the range of temperate grasslands. To date, the disturbance-promoting-diversity paradigm has taken a univariate approach to the drivers of biodiversity; rainfall is seen as a key driver of productivity, which then drives diversity, mediated by disturbance. We argue that this framework is too simplistic as biodiversity drivers are multivariate. We suggest that the accumulation of phytomass (live and dead plant material) is an important determinant of diversity in grassy ecosystems and that phytomass accumulation is governed by multiple drivers (of which disturbance is just one). For fauna, it is structure – not biomass – that determines habitat suitability, and this can be moderated by both abiotic and biotic drivers. The assumption that there is a consistent effect of disturbance on diversity through the range of temperate grassland settings in southern Australia ignores the likelihood that biodiversity also responds to other factors such as spatial heterogeneity in the environment, resource availability and climatic variation. We developed a conceptual model of the multivariate drivers of grassland diversity that explores mechanisms underpinning patterns of species richness. Despite four decades of research, it is clear that our understanding of the multivariate drivers of diversity across the range of temperate grasslands in Australia is still incomplete. Further research into the conditions under which disturbance is required to maintain biodiversity in grasslands is integral to conservation planning in these endangered systems. We review the literature from temperate grasslands in south-eastern Australia to develop a conceptual model that proposes the key multivariate drivers that underpin diversity. In this model, accumulated biomass governs the structure of grasslands and this, in turn, affects diversity through its effects on resource availability. We outline the key direct drivers of diversity in temperate grasslands – disturbance, resources and regeneration – in an effort to better understand how grasslands vary ecologically across their range, and why structure, function and diversity are more than outcomes of the amount of biomass singularly. Despite four decades of research, it is clear that our understanding of the multivariate drivers of diversity across the range of temperate grasslands in Australia is still incomplete. We identify key research questions that must be addressed to advance the conservation management of these endangered ecosystems. [ABSTRACT FROM AUTHOR]

Conserving alpine ecosystems and the plant communities they contain using ex situ conservation requires an understanding of seed longevity. Knowledge of seed longevity may determine the effectiveness of ex situ seed banking for alpine plant conservation, and may provide insight into plant recruitment in situ. We sought to determine the influence of elevation and climatic variables, as well as plant and seed traits, on the seed longevity of 57 species inhabiting a unique biome, (sub-)alpine regions of mainland Australia. Seed longevity was estimated using controlled accelerated ageing tests to determine the time taken for seed viability to fall by 50%. We found that, across the study species, like alpine seeds elsewhere in the world, Australian alpine seeds are relatively short-lived and overall shorter-lived than Australian plants in general. Seed mass and elevation explained most of the variation in seed longevity among the Australian alpine species considered. Species with larger seed mass, and collections made at higher elevations, were found to have relatively short-lived seeds. Phylogeny, however, explained very little of the variation in longevity. Our results suggest that viability testing for Australian alpine seeds in ex situ seed banks should be conducted with shorter intervals than for the non-alpine flora. This study highlights how seed longevity in the Australian Alps is not dictated primarily by evolutionary lineage but rather by a complex combination of environmental variables and intrinsic seed characteristics. Potential implications for conservation ex situ and in situ in the context of climate change are discussed. [ABSTRACT FROM AUTHOR]

Seed science is fundamental to many fields of endeavour, from agricultural production, to restoration, and conservation of threatened species and communities. This is especially the case in Australia which has seen hugely increased involvement and outputs from seed scientists across many sectors over the last three decades. This escalation in research is reflected in the program and outcomes of the first National Seed Science Forum that was held in March 2016 and was attended by delegates representing many scientific institutions, industry, non-government organisations and volunteer groups. There were delegates from nine countries, and keynote presentations and workshops by global leaders in seed science. A key outcome of the Forum was the unique opportunity for discussion and collaboration across sectors. Another key outcome of the Forum, the Seed Science Special Issue of the Australian Journal of Botany, captures some of the emerging topical research and themes seed scientists are working on. Of particular note is the growth in germplasm conservation of native and agricultural floras, in line with, and at the forefront of, international collaborative efforts. The other strong theme across the Forum is the increasingly sophisticated use of seeds in restoration and the enabling technological advances. Future potential advances in Australian seed science are discussed. [ABSTRACT FROM AUTHOR]

Restoration is vital for the re-establishment and maintenance of biodiversity of temperate grassy woodlands, but limited understanding of species' reproductive biology restricts the efficiency of restoration practice. The present study aimed to explore germination cues and seed dormancy of Dianella longifolia R.Br., Dianella revoluta R.Br., and Stackhousia monogyna Labill., three native Australian forb species that have been difficult to germinate in large-scale restoration projects. A series of experiments investigated the effect of various dormancy-alleviation or germination-promoting treatments on germination of these three species. Significant interactions were found between some treatments and germination temperatures for D. longifolia and S. monogyna, but no significant interactions were observed for D. revoluta. At optimal temperatures, scarification treatment produced the highest mean germination for D. longifolia and S. monogyna, and this was significantly higher than for control seeds. Storage conditions (ambient, dry, frozen) did not decrease viability after 10 weeks of storage, suggesting that seeds of all species are likely to be orthodox. To maximise the effectiveness of seed use in restoration programs, it is recommended that scarification of D. longifolia and S. monogyna seed be undertaken to improve field germination. Further work should focus on how to scale up application of the scarification treatment, optimise methods for alleviating dormancy in D. revoluta, and examine the ecological cues that naturally alleviate dormancy and promote germination of these three species. [ABSTRACT FROM AUTHOR]

Intraspecific ploidy variation is an important component of angiosperm biodiversity; however, this variation is rarely considered in conservation programs. This is of particular concern when conservation activities include augmentation, reintroduction or ecological restoration because there are potentially negative consequences when ploidy variants are unintentionally mixed within populations. We surveyed regional ploidy variation in the Lepidosperma costale Nees species complex (Schoeneae: Cyperaceae) in the South West Australian Floristic Region, an international biodiversity hotspot. Several L. costale sensu lato populations are threatened by iron-ore extraction, including the rare L. gibsonii R.L.Barrett, and these populations are the subject of ecological restoration programs. The DNA ploidy of 2384 individuals from 28 populations across the range of the species complex was determined and four DNA ploidy levels were discovered, namely, diploid, triploid, tetraploid and pentaploid. Diploids and tetraploids were the most common cytotypes and were largely geographically segregated, even at an exhaustively studied contact zone. Triploids were found at a low frequency in two populations. The rarity of triploids suggests substantial interploidy sterility, and that mixing of ploidy variants should, therefore, be avoided when restoring L. costale s.l. populations. These data provide a guide for L. costale s.l. germplasm collection and suggest that polyploidy may be an important driver of diversification in these sedges. [ABSTRACT FROM AUTHOR]

The article describes the participation of two members of the Australian National Botanic Garden's (ANBG) National Seed Bank team at the International Society for Seed Science conference held in Spain, it presents their research on seed germination in rare species of conservation concern and the importance of light on the germination of Australia's tropical mountain cloud forest species.

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]

Dispersal of plant propagules by ocean currents can result in long-distance dispersal and is important for the persistence of coastal species. However, the ability of such species to disperse via the ocean is often unknown because there is relatively little evidence that demonstrates that seeds or fruits can float and survive for extended periods in seawater. Furthermore, the seed or fruit traits, and intraspecific variation in these traits, that facilitate buoyancy remain largely unidentified. The genus Scaevola (L.) contains several widespread coastal species that may be capable of oceanic dispersal, such as S. crassifolia (Labill). We collected fruits of S. crassifolia along 700 km of a latitudinal environmental gradient. These fruits were used to determine the influence of fruit morphology and anatomy on fruit buoyancy. Morphological and anatomical variation in S. crassifolia was associated with dispersal potential. Our empirical data demonstrated that fruits with larger aeriferous mesocarp layers have greater buoyancy and, therefore, enhanced capacity for long range oceanic dispersal. Of three characters hypothesised to affect buoyancy (aeriferous mesocarp, air pockets in empty locules, and number of vascular cavities), only the properties of the mesocarp were significant. Intraspecific variation can significantly affect dispersal potential, and should not be overlooked in dispersal ecology. Seed dispersal is important for the persistence of plant species. Here, we investigated the amount of within-species variation in fruit morphology of a coastal species, and the effect this had on buoyancy. We found that fruits with larger aeriferous mesocarp layers had the greatest buoyancy, and therefore greater capacity for oceanic dispersal. Intraspecific variation that imparts greater buoyancy and promotes oceanic dispersal may facilitate range shifts and assist coastal species to persist through climate change. [ABSTRACT FROM AUTHOR]

Seeds of many coastal plants can survive exposure to seawater and may be dispersed long distances by the ocean. The salt tolerance or avoidance strategies of seeds are poorly understood, even though these traits may fundamentally influence dispersal and recruitment in coastal dunes. This research aimed to demonstrate how salt exclusion or localization within germinating seeds may affect salt tolerance. To determine the response of seeds to external salinity during imbibition (water uptake), it was necessary to quantify uptake and spatially resolve the internal distribution of salt. Flame photometry was used to quantify salt concentration in imbibing seeds and a new application of full-spectrum X-ray mapping allowed visualization of the spatial distribution and relative abundance of salt. As external salinity increased, salt-sensitive Spyridium globulosum ( Rhamnaceae) seeds accumulated sodium and chlorine in the seed embryo, while potassium was increasingly displaced and germination was reduced. Conversely, salt-tolerant Ficinia nodosa ( Cyperaceae) seeds avoided ion uptake and germination was not affected by imbibition in high sodium chloride ( NaCl) concentrations. These results provide insight into mechanisms of salt tolerance/avoidance during imbibition and early germination and suggest that oceanic dispersal can be a viable explanation for the distribution of some plant species. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173, 129-142. [ABSTRACT FROM AUTHOR]

Manycoastal plant species are widely distributed, including several pan-global species. Long-distance dispersal and physiological resilience of diaspores (i.e. the plant dispersal unit encompassing the seed and any additional surrounding or attached tissues at dispersal) to adverse environmental conditions are possible contributors to the presence of species over hundreds of kilometres of coastline. Dispersal by water (hydrochory) may occur in coastal habitats. This study investigated diaspore traits considered important for oceanic hydrochorous dispersal, including morphology, buoyancy and survival in seawater, and germination under saline conditions for 13 species common to Holocene dune communities in Western Australia. Of the diaspores of 13 species dominant in this coastal community, 11 floated in seawater, with 7 having >50% of diaspores buoyant after 14 days and some diaspores remaining buoyant for 70 days. Of the 10 species that germinated, diaspores of 9 survived exposure to seawater for up to 70 days. Germination of physiologically dormant seeds contained within indehiscent woody fruits and physically dormant seeds was least affected by time in seawater. The effects of varying concentrations of NaCl (0-500 mM) on germination differed between species, but most were able to recover and germinate when transferred to non-saline water. Three different patterns of salt response were observed. It appears likely a combination of diaspore traits, rather than a single factor, facilitate oceanic hydrochorous dispersal. [ABSTRACT FROM AUTHOR]