Australian Plant Research Articles

Soil density specification ranges to optimise plant water use and root growth for phytocapping and urban greening projects

Soil density or compaction is one of the key variables that need to be specified for designed soil profiles as part of urban greening. Examples include land rehabilitation (mining), waste containment (phytocapping), stormwater infrastructure (bioretention basins) and green infrastructure (green roofs and street trees). This study investigates the impact of a range of specified soil densities on plant water use and root development. Native Australian plant species selected for the study include: the C4 and C3 grasses, Themeda triandra and Microlaena stipoides respectively; the Eucalyptus trees, E. camaldulensis and E. cladocalyx; and the nitrogen-fixing pioneer trees, Acacia mearnsii and Allocasuarina verticillata. The plants were established at four soil density (compaction) levels: 72, 77, 82, and 87 % MDD (maximum dry density) in tall cylinders with weekly plant water use measurement over 8 months. Root growth was analysed using WinRhizo image analysis. The experimental results were used to create generalisable models for root length density (RLD), root diameter and plant water use. The models for RLD and plant water use were parabolic in nature, revealing clear optimum ranges that could be used to guide soil density specification. Root diameter provided additional insight into the allocation of resources to root thickening above a threshold soil density of 87 % MDD, indicating plant allocation of resources towards penetrating highly compacted soils. There were correlations between plant water use and RLD that were moderate and significant, particularly for grasses. Notably, T. triandra had the greatest mean RLD, thickest roots and plant water use at 16.8cm/cm3, 0.18 mm and 10mm/week, respectively. Findings demonstrate that RLD and plant water use can be optimised together within practically achievable soil density specification ranges that are sensitive to the pitfalls of both excessively low and excessively high soil densities. Recommended soil density specification ranges include: 75–82 % MDD with plant performance within 5 % of optimum (considered excellent), 74–84 % MDD with plant performance within 10 % of optimum (considered good) and 73–85 % MDD with plant performance within 15 % of optimum (considered fair). Within these ranges, plant water use and root growth performance is well balanced with practical achievement of the soil density ranges. Due to the use of %MDD, the modelled results can be usefully generalised for any soil type. Implementation of these specifications for urban greening and phytocap projects will optimise plant growth, transpiration and hydrological function while maintaining root networks essential for establishing and maintaining resilient living infrastructure.

Bio-functional properties of Jilungin (Terminalia canescens).

Jilungin (Terminalia canescens) is a native Australian plant and the Indigenous "Nyul Nyul" people of the Kimberleyregion of Western Australia use its leaves to make herbal tea. Due to the rise in the popularity of drinking Jilungin tea among the consumers in Australia and internationally, it is important to study the nutritional and health-beneficial properties as well as safety of Jilungin leaves. This study aims to determine the nutritional composition, anti-nutritional factors, antimicrobial and antidiabetic properties of Jilungin leaves. Also, the phytochemical profiling using UHPLC-MS/MS (Ultra-performance liquid chromatographymass spectrometry) and antioxidant activity of Jilungin methanolic extracts and herbal infusion were investigated. The safety of the leaves and infusion was also investigated by using in vitro mammalian cell lines (Caco2, HT29, and HepG2) through cell viability assays. The leaves are rich in dietary fiber (43.9%) and linoleic acid (30.4% of total fatty acids). Phytochemical profiling revealed ellagic acid, geraniin, pedunculagin, and punicalagin as the major bioactive compounds. The results also demonstrated that Jilungin has strong antioxidant and antidiabetic activities. A significant (p<0.01) strong positive correlation was observed between the high antioxidant activity of Jilungin infusion with the major bioactive compounds. Jilungin extracts (50mg/mL) exhibited strong antimicrobial activity against Staphylococcus aureus and Bacillus cereus. Its infusion and methanolic extract were safe on the studied cell lines (Caco-2, HT29, and HepG2) at higher concentrations of 66.6 and 98mg/mL, respectively. Therefore, Jilungin teas or infusions could be a safe and effective way to promote health and well-being. PRACTICAL APPLICATION: Jilungin tea is very popular among consumers in Australia and is gaining popularity worldwide. The current study will increase knowledge on the nutritional aspects and safety of the Jilungin use.

Mobilizing International Australian Collections Locally for Global Benefit

From the earliest days of Australian colonization and exploration, botanical collections have been sent to herbaria overseas for western scientific study. Where there is a duplicate set, collections have been repatriated back to Australia with time, but many specimens remain housed overseas. These specimens document the floral diversity of Australian ecoregions that have now been altered, and of species that have not yet been described and may now have been lost to our ecosystems. Many such collections have type specimens, and others have historical exploration and botanical significance, many of which are not readily available for taxonomic and cultural research. One such collection, the Cambridge University Herbarium (CGE), is the fourth largest herbarium in the United Kingdom (Gardiner 2018) and contains more than 13,700 specimens of Australian origin. A collaborative project between the Western Australian Herbarium (PERTH) and CGE, supported by The Winston Churchill Memorial Trust, Australia, has enabled Australian collections to be located, updated, digitized, mobilized, and shared—decolonization and repatriation in digital form. With only five weeks to undertake collection-based activities at CGE, the effort focused on the Australian vascular plant collections. These were systematically located and retrieved from the CGE world collections of flowering plants and ferns (conveniently geographically arranged), and the John Lindley and Charles Fox Bunbury collections, which were only partially incorporated into the world collecitons. Curation was limited to significant repairs and incorporation of loose specimens into the collections. Annotated type specimens were placed within separate folders for easy future identification and curation. Barcodes were adhered to each sheet, and basic metadata was gathered prior to imaging (taxonomic name on the sheet, storage location, type status). Sheets were imaged using two Nikon D850 45.7MP digital single-lens reflex cameras in a lightboxes; image files were converted to 16-bit TIFF for archival storage, full-sized JPGs, and 1MB JPGs for online delivery. With approximately half of the specimens transcribed in September, 2024, preliminary findings include the following: The majority of the Australian collections in CGE are from Western Australia, Tasmania, New South Wales, and South Australia with significantly fewer collections from other Australian states and territories. The majority of specimens were collected in the 1800s and early 1900s, with dominant collectors being James Drummond (collecting in Western Australia), Ronald Gunn (collecting in Tasmania), William Philip Hiern, John Lhotsky, Joseph Jackson Lister, Sir Thomas Livingstone Mitchell, Georgiana Molloy, Fredrick Stimpson Salisbury, and William John Swainson. Prominent individual personal herbarium collections represented included those of Charles Morgan Lemann (1806–1852), John Lindley (1799–1865), John Stevens Henslow (1796–1861) and Charles Edward Moss (1870–1930). Most specimens have little locality information (e.g, "New Holland", "Van Diemen's Land", "Swan River"). More than 475 type specimens have been identified. More than 145 vascular plant families, 875 genera, and ca. 4500 (many non-current) species are housed within the collections (representing approximately 15% of Australian vascular plants). The majority of the Australian collections in CGE are from Western Australia, Tasmania, New South Wales, and South Australia with significantly fewer collections from other Australian states and territories. The majority of specimens were collected in the 1800s and early 1900s, with dominant collectors being James Drummond (collecting in Western Australia), Ronald Gunn (collecting in Tasmania), William Philip Hiern, John Lhotsky, Joseph Jackson Lister, Sir Thomas Livingstone Mitchell, Georgiana Molloy, Fredrick Stimpson Salisbury, and William John Swainson. Prominent individual personal herbarium collections represented included those of Charles Morgan Lemann (1806–1852), John Lindley (1799–1865), John Stevens Henslow (1796–1861) and Charles Edward Moss (1870–1930). Most specimens have little locality information (e.g, "New Holland", "Van Diemen's Land", "Swan River"). More than 475 type specimens have been identified. More than 145 vascular plant families, 875 genera, and ca. 4500 (many non-current) species are housed within the collections (representing approximately 15% of Australian vascular plants). Full transcription of label data (collector, collection date, collection number, locality information, and other collection information) and taxonomic curation is ongoing. Data and high resolution images will be made available soon to the scientific community, historians, and the public for data curation and annotation through the Atlas of Living Australia and other digital platforms. Access to these specimens will be invaluable for botanical research in this age of accelerated biodiversity loss, and as travel to, or shipping of, physical specimens is increasingly fraught and costly.

Harmonising Terminology and Records of Plant Invasion Status Across Federally Managed Countries

Plant invasions are a major threat worldwide, posing significant ecological and economic threats. In federally managed countries—where policy implementation is divided among various jurisdictions under a central federal government—alien plant species pose an even more difficult challenge for management at the national scale due to the fragmented nature of information provided by independent jurisdictions. This has led to inconsistencies in the terminology used to describe species status along the introduction-naturalisation-invasion continuum and disparities in the classification reported by each jurisdiction. Such contrasting information impedes data interoperability at the national level, hampering efficient management and biosecurity actions. This highlights the urgent need for a harmonised framework to ensure data interoperability on biological invasions. Australia, with its rich endemism and federal structure, provides a robust case to harmonise disparate data sources. We first reviewed the different terminology frameworks proposed for biological invasions (either ecologically- or policy-based, emphasising, respectively, species' ability to overcome ecological barriers, and impact). We then integrated such frameworks to develop a harmonised framework of invasion terminology for Australia, while also considering the language used by states' Australian herbaria (Martín-Forés et al. 2024). To do so, we developed an R script to compare existing Australian data sources for vascular plant taxa, including the Australian Plant Census (APC), state and territory censuses, and the Australian Global Register of Introduced and Invasive Species (GRIIS). The script consists of a harmonised workflow that identifies mismatches in definitions and records among these sources, enabling us to propose prioritisation procedures to tackle these, and subsequently integrate information into a unified status for each species at the national scale (Martín-Forés et al. 2023b). The integration of these contrasting data culminated in the creation of a standardised dataset at the Australian national scale, the Alien Flora of Australia (AFA) (Martín-Forés et al. 2023a, Martín-Forés et al. 2023c). The AFA poses a significant advancement in the management of alien flora. The up-to-date information presented in the AFA can aid in early warning of species introduction, facilitate decision-making at various levels, and enhance national biosecurity. The associated script is ready to be implemented into new versions of the AFA with updated releases of any of the data sources, streamlining future efforts to track alien flora across Australia. The benefits of improving alien species data interoperability are numerous and far-reaching. Ensuring consistency in terminology and classification across jurisdictions is crucial for effective communication and collaboration among stakeholders and across different policy levels. Standardised data allow for more accurate monitoring and reporting of alien species, supporting the development of strategies at different jurisdictional levels for managing alien species, leading therefore to better-informed management decisions. Early detection and rapid response are critical components of effective biosecurity, and the AFA-harmonised dataset enables these actions by providing timely and accurate information at the Australian national scale. The implementation of the AFA and the associated R script represents a significant step forward in the harmonisation of data sources for detecting biological invasions in Australia. By ensuring consistency in terminology and classification, facilitating early detection and rapid response, and supporting collaborative efforts, harmonised data can enhance the effectiveness of management practices and facilitate conservation initiatives. However, this is just the beginning, as the workflows and script can be modified to suit any other federally managed country, alleviating the complex interplay of biosecurity regulations at different scales and among jurisdictions, enhancing the effectiveness of biosecurity measures. By adopting similar approaches, countries around the world can improve their capacity to manage alien species and protect their unique biodiversity. The model facilitates the sharing of information and best practices among jurisdictions within a given country, and among countries, thus fostering a collaborative approach to biosecurity both at national and international scales. Harmonising information on biological invasions also has important ecological implications, as alien species can disrupt ecosystems, outcompete native species, and alter habitat structure and function. By improving our ability to monitor and manage alien species, we can help protect biodiversity and maintain ecosystem services. Besides, the economic benefits are also significant, as alien species can cause substantial damage to agriculture, forestry, fisheries, and other sectors, leading to costly control measures and economic losses. By providing a robust framework for data interoperability on biological invasions, we can reduce the economic impact of alien species by enabling synergies among jurisdictions, and therefore more efficient and targeted management efforts. Thus, harmonisation on biological invasions is crucial for effective biosecurity at the national and international levels. The creation of the AFA demonstrates the benefits of data interoperability, providing a model that can be adapted and implemented in other contexts.

A comprehensive analysis and risk evaluation of microplastics contamination in Australian commercial plant growth substrates: Unveiling the invisible threat

In Australia, quality standards for composts and potting mixes are defined by AS4454-2012 and AS3743-2012. These standards outline key parameters, including physicochemical properties, nutrient content, and plant toxicity. However, they do not address emerging pollutants like microplastics (< 1mm). This study investigates the prevalence and characteristics of MPs in commercial plant growth substrates (PGS), including nineteen potting mixes and five composts, revealing a significant occurrence of MPs, with concentrations ranging from 233 to 7367 particles Kg-1 and an average of 1869 ± 109 particles Kg-1. MPs categorized by shape, size, and color, with fragments (491 ± 34 particles Kg-1), white colour (3700 ± 917 particles Kg-1), and size 500µm being predominant. The polymer composition was diverse, with polyethylene being the most prevalent, followed by polypropylene and others. Polyterpene, Polyalkene, Pentaerythritol, and Propylene glycol were identified in PGS for the first time. The structural equation model showed that physicochemical properties like pH, EC, TOC, and heavy metals influence MPs abundance and characteristics. The Polymer Risk Index and Pollution Load Index indicated varying risk levels among the samples. These findings highlight the need to address MPs contamination in PGS to ensure ecosystem safety and human health. Environmental ImplicationsThe study reveals significant microplastic contamination in Australian commercial PGS, with compost exhibiting higher levels than potting mixes. Application of these contaminated substrates can lead to microplastic release, which can further alter soil properties, disrupt microbial communities, and leach environmental toxins. Current regulations primarily target larger plastic items, neglecting the issue of microplastics (<1mm). The findings underscore the necessity for updated standards and quality controls for commercial PGS. Enhancing public awareness and improving waste sorting are crucial steps to mitigate contamination. Effective source separation is essential for producing high-quality compost and potting mixes. Collaborative efforts among policymakers, industries, and communities are vital for advancing waste management practices and environmental protection.

Ultra-Short-Term Photovoltaic Power Prediction by NRGA-BiLSTM Considering Seasonality and Periodicity of Data

Photovoltaic (PV) power generation is highly stochastic and intermittent, which poses a challenge to the planning and operation of existing power systems. To enhance the accuracy of PV power prediction and ensure the safe operation of the power system, a novel approach based on seasonal division and a periodic attention mechanism (PAM) for PV power prediction is proposed. First, the dataset is divided into three components of trend, period, and residual under fuzzy c-means clustering (FCM) and the seasonal decomposition (SD) method according to four seasons. Three independent bidirectional long short-term memory (BiLTSM) networks are constructed for these subsequences. Then, the network is optimized using the improved Newton–Raphson genetic algorithm (NRGA), and the innovative PAM is added to focus on the periodic characteristics of the data. Finally, the results of each component are summarized to obtain the final prediction results. A case study of the Australian DKASC Alice Spring PV power plant dataset demonstrates the performance of the proposed approach. Compared with other paper models, the MAE, RMSE, and MAPE performance evaluation indexes show that the proposed approach has excellent performance in predicting output power accuracy and stability.

Antibacterial and Antibiofilm Properties of Native Australian Plant Endophytes against Wound-Infecting Bacteria.

The wound management field faces significant challenges due to antimicrobial resistance (AMR) and the complexity of chronic wound care. Effective wound treatment requires antimicrobial dressings to prevent bacterial infections. However, the rise of AMR necessitates new antimicrobial agents for wound dressings, particularly for addressing bacterial pathogens like methicillin-resistant Staphylococcus aureus (MRSA). Endophytic fungi, known for producing diverse bioactive compounds, represent a promising source of such new agents. This study tested thirty-two endophytic fungi from thirteen distinct Australian native plants for their antibacterial activity against S. aureus. Ethyl acetate (EtOAc) extracts from fungal culture filtrates exhibited inhibitory effects against both methicillin-sensitive S. aureus ATCC 25923 (MIC = 78.1 µg/mL) and MRSA M180920 (MIC = 78.1 µg/mL). DNA sequence analysis was employed for fungal identification. The most active sample, EL 19 (Chaetomium globosum), was selected for further analysis, revealing that its EtOAc extracts reduced S. aureus ATCC 25923 biofilm formation by 55% and cell viability by 57% to 68% at 12 × MIC. Furthermore, cytotoxicity studies using the brine shrimp lethality test demonstrated low cytotoxicity up to 6 × MIC (25% mortality rate) with an LC50 value of 639.1 µg/mL. Finally, the most active sample was incorporated into polycaprolactone (PCL) fiber mats via electrospinning, with resultant inhibition of S. aureus species. This research underscores the potential of endophytic fungi from Australian plants as sources of substances effective against common wound pathogens. Further exploration of the responsible compounds and their mechanisms could facilitate the development of wound dressings effective against MRSA and innovative biofilm-resistant electrospun fibers, contributing to the global efforts to combat AMR.

Extraction and Surface Activity of Australian Native Plant Extracts: Alphitonia excelsa

Saponin surfactants extracted from plants have significant potential applications in many industries. The interfacial properties of extracts of Alphitonia excelsa, a native Australian plant rich in saponins, have been characterised to assess their suitability as dual-purpose foaming and antibacterial additives. Two sources of the plant (Adelaide Botanic Gardens and homelands of Chuulangun Aboriginal Corporation) were investigated to look for alteration of properties as a result of differences in cultivation and geographic location. Two methods of saponin extraction (water and water/ethanol mixtures) were investigated to determine differences in extraction efficiency and performance. Distinct differences were observed between the traditional analytical analysis (for saponin content) of the extracts based on source and extraction method; however, these differences were not as stark when considering the effect of the extracts on air–water interfacial tension and dilatational rheology, with extraction method proving to be the single biggest factor in extract efficacy. The data obtained point toward the presence of an altered array of surface-active species (different relative amounts of particular saponins in the water/ethanol extracted material) as a function of the extraction method. All extracts presented some antibacterial effect, albeit modest. This work highlights that the extraction method needs to be carefully considered and tailored for a given application.

Morphological Seed Traits Predict Early Performance of Native Species to Pelletized Seed Enhancement Technologies.

Native seeds are a finite resource, and their inclusion in revegetation is vital for supporting restoration outcomes that are both effective and scalable. Pelletized seed enhancement technologies (SETs) offer a promising solution to improve seed use efficiency in ecological restoration. Yet, knowledge of how diverse suites of native species perform when pelletized is required to optimize the application of SETs to the many species and ecosystems where restoration is required. Using a greenhouse trial of 64 Australian plant species, we assessed species performance to pelleting by evaluating (1) overall species amenability to pelleting based on total emergence and survival and (2) how pelleting modifies the rate of emergence based on average time to emergence, emergence rate index, and time spread of emergence. We investigated the potential for using morphological seed traits (seed endosperm:seed ratio, seed length, seed area, and seed coat thickness) to predict performance outcomes, by identifying traits that may aid in the prediction of species amenability to pelleting and emergence speed when pelletized. We found that some species demonstrate high amenability to pelleting and that pelleting can modify the emergence rates for many species. This work advances our understanding of the applicability of SETs for diverse native species, demonstrating the application of such technologies for meeting ecological restoration goals.

Identification and expression analysis of Phosphate Transporter 1 (PHT1) genes in the highly phosphorus-use-efficient Hakea prostrata (Proteaceae).

Heavy and costly use of phosphorus (P) fertiliser is often needed to achieve high crop yields, but only a small amount of applied P fertiliser is available to most crop plants. Hakea prostrata (Proteaceae) is endemic to the P-impoverished landscape of southwest Australia and has several P-saving traits. We identified 16 members of the Phosphate Transporter 1 (PHT1) gene family (HpPHT1;1-HpPHT1;12d) in a long-read genome assembly of H. prostrata. Based on phylogenetics, sequence structureand expression patterns, we classified HpPHT1;1 as potentially involved in Pi uptake from soil and HpPHT1;8 and HpPHT1;9 as potentially involved in Pi uptake and root-to-shoot translocation. Three genes, HpPHT1;4, HpPHT1;6and HpPHT1;8, lacked regulatory PHR1-binding sites (P1BS) in the promoter regions. Available expression data for HpPHT1;6 and HpPHT1;8 indicated they are not responsive to changes in P supply, potentially contributing to the high P sensitivity of H. prostrata. We also discovered a Proteaceae-specific clade of closely-spaced PHT1 genes that lacked conserved genetic architecture among genera, indicating an evolutionary hot spot within the genome. Overall, the genome assembly of H. prostrata provides a much-needed foundation for understanding the genetic mechanisms of novel adaptations to low P soils in southwest Australian plants.

Ant mimicry in Australian plant bugs: a new genus (Heteroptera: Miridae: Austromirini: Carenotus gen. nov.), eight new species, myrmecomorphic traits, host plants and distribution.

The Australian plant bug tribe Austromirini consists of ant-mimetic taxa which are poorly known, with no information of their phylogenetic relationships and ant-mimetic traits. In this study, we examined nearly 1000 ingroup specimens and developed a comprehensive morphological dataset comprising 37 characters, which was analysed both weighted and unweighted, using 'Tree analysis using New Technology' (TNT ) software. A single minimal length phylogenetic tree was found, comprising a monophyletic group of ant-mimetic taxa, that included Myrmecoroides rufescens , Myrmecoridea sp., Kirkaldyella spp. and eight species of a new genus, Carenotus gen. nov. The myrmecomorphic traits of Carenotus and allied ant-mimetic taxa are documented and analysed phylogenetically, in conjunction with genitalic characters. Carenotus is defined by the myrmecomorphic colour patterning of the abdominal venter, whereas the ingroup species relationships are supported by genitalic characters alone. Carenotus is described as new with eight included species as follows: C. arltunga sp. nov., C. louthensis sp. nov., C. luritja sp. nov., C. pullabooka sp. nov., C. scaevolaphilus sp. nov., C. schwartzi sp. nov., C. tanami sp. nov. and C. yuendumu sp. nov. Host plant associations are also documented, ranging from host plant specificity and genus-group preferences to host plant generalism. The distribution of Carenotus species is documented with reference to phytogeographic subregions, with all species being semi-arid and arid dwelling. The male and female genitalia of Kirkaldyella pilosa and K. rugosa are described and illustrated, for comparative and phylogenetic purposes. This research expands our knowledge on the plant bug tribe Austromirini and has broader implications for myrmecomorphic research in the suborder Heteroptera. ZooBank: urn:lsid:zoobank.org:pub:2FF9BE23-38A6-42B4-8488-74F216D8237F.

Triplinones A-H: Anti-Inflammatory Arylalkenyl α,β-Unsaturated-δ-Lactones Isolated from the Leaves of Australian Rainforest Plant Cryptocarya triplinervis (Lauraceae).

Our ongoing exploration of Australian rainforest plants for the biodiscovery of anti-inflammatory agents led to the isolation and structural elucidation of eight new arylalkenyl α,β-unsaturated-δ-lactones, triplinones A-H (1-8), from the leaves of the Australian rainforest plant Cryptocarya triplinervis B. Hyland (Lauraceae). The chemical structures of these compounds were established by NMR spectroscopic data analysis, while their relative and absolute configurations were established using a combination of Mosher ester analysis utilizing both Riguera's and Kishi's methods, ECD experiments, and X-ray crystallography analysis. Compounds 1-8 exhibited good inhibitory activities toward nitric oxide (NO) production in lipopolysaccharide (LPS) and interferon (IFN)-γ induced RAW 264.7 macrophages, in particular compounds 1-3 and 5, with IC50 values of 7.3 ± 0.5, 6.0 ± 0.3, 5.6 ± 0.3, and 5.4 ± 2.5 μM, respectively.

Woody plant phytolith morphology and representation in surface sediments across the Northern Territory, Australia

Phytoliths are a good tool for investigating vegetation change in northern Australia. However, there is a lack of phytolith reference material across the Australian continent, particularly for woody plants. The development of reference material from woody plants is critical to understand regional patterns of phytolith production and preservation. This study analyses phytolith material from 40 woody plants to examine morphological and anatomical variation in phytolith production among Australian plant families. This is paired with phytolith assemblages from nine surface sediment samples to assess the representation and preservation of woody plant phytolith morphotypes. All woody plant species examined produce identifiable phytolith morphotypes, but most morphotypes cannot be differentiated between woody eudicots, monocots, and conifers. However, some woody plant morphotypes do have good potential for taxonomic or anatomical discrimination of plant groups. The analysis of surface sediment phytolith assemblages reveals that not all woody plant morphotypes preserve equally in surface sediments, potentially restricting their ability for taxonomic discrimination. Finally, the relevance of phytolith morphotypes for palaeoecological reconstruction is discussed.

Drought and mycorrhizal inoculation affect growth and morphology of Australian stormwater biofilter plants

This study evaluated the effect of mycorrhizal inoculation on six common Australian biofilter plant species using a pot experiment. We divided 120 pots planted with six common biofilter species into four treatments: control water-deficit, inoculated water-deficit, control well-watered, and inoculated well-watered. Inoculated treatments were inoculated with a commercially available blend of arbuscular mycorrhizal fungi spores. While well-watered pots were watered to pot capacity daily, water-deficit pots were subjected to a simulated drought that lasted six weeks until harvesting. All plants inoculated with arbuscular mycorrhizal fungi developed greater total root surface area, plant biomass, and plant relative growth rate. Which are associated with better stormwater nutrient removal. Mycorrhizal inoculation also increased the average root diameter, total length, and surface area of thick roots (diameter > 1 mm) of six species, which are essential to maintain the infiltration rates and hydraulic functions of biofilter systems. Moreover, an increase in shoot biomass following inoculation was also observed across six species, potentially contributing to higher water loss and stormwater volume reduction. Although the water-deficit condition greatly limited the effects of mycorrhizal inoculation on other morphological traits, we still observed the benefits of inoculation on total root length and surface area in well-watered J. pallidus and C. appressa. As drought stress imposes limitations on the effects of inoculation, we recommend inoculation should be carried out in advantageous times, such as during wet periods before the drought season for the optimal colonization and plant biomass and morphological responses. Additionally, selecting mycorrhizae-responsive species like C. appressa, J. pallidus, and G. sieberiana can result in favorable outcomes.

Seasonal Patterns and Allergenicity of Casuarina Pollen in Sydney, Australia: Insights from 10 Years of Monitoring and Skin Testing

Casuarina (Australian pine, She-oak) is native to Australia and South East Asia and is known for its abundant wind-borne pollen. Despite not being considered a major aeroallergen, some patients report respiratory symptoms upon exposure, with positive skin prick tests (SPT) to Casuarina pollen extract. This study investigates Casuarina pollen dispersal patterns in Sydney, Australia, over a 10-year period, from 2008 to 2018, revealing a bimodal distribution of pollen from September to October (southern hemisphere spring) and February to March (mid-late summer). Analysis of historical SPT data shows 20% of individuals with respiratory allergies reacting positively to Casuarina pollen extract, with almost 90% of these also reacting to grass pollen, suggesting potential cross-reactivity. Notably, there are no exclusive reactions to Casuarina pollen. Understanding the prolonged pollen season underscores the importance of year-round monitoring for accurate characterization. Currently lacking are commercially available skin test extracts or specific IgE assays for Casuarina sensitization, necessitating challenge studies to confirm clinical symptoms directly attributable to Casuarina pollen. By elucidating the seasonal dynamics and meteorological drivers of Casuarina pollen dispersion, alongside the potential allergenicity suggested by skin prick tests, this study paves the way for improved management of Casuarina-related allergies and highlights the critical need for further research on native Australian plant allergens.

APCalign: an R package workflow and app for aligning and updating flora names to the Australian Plant Census

Here we present ‘APCalign’, an R package and accompanying browser-sourced application to align and update scientific names for Australian vascular plants to the most likely currently accepted name in the Australian Plant Census (APC) or a name in the Australian Plant Names Index (APNI). Scientific names are the label assigned to unique taxon concepts by the scientific community, but this common terminology is most useful if a taxon concept is consistently referred to by the same name. These links can be broken because of either spelling mistakes or taxonomic changes. Automated tools are required to resolve taxon lists, aligning and updating long lists of possibly erroneous scientific names to the most likely currently accepted names. It is essential that tools specific to the APC/APNI be developed, because these lists specify an endorsed national-level nomenclature used in government legislation and include the uniquely Australian concept of phrase names, absent in global taxonomic datasets. To align input names to names within the APC or APNI, ‘APCalign’ works progressively through a sequence of checks that combine different permutations of the input name, exact versus fuzzy matches, matches that consider the entire name input versus a subset of words, and character strings that indicate a name can be resolved only to a genus or family. The aligned names are then, when possible, updated to a currently accepted taxon concept within the APC. This package should facilitate all research outputs that require diverse scientific name lists to be merged or outdated lists to be updated.

A near-complete dataset of plant growth form, life history, and woodiness for all Australian plants

Tabular records of plant-trait data are essential for diverse research purposes. Here we present scorings for a trio of core plant traits, plant growth form, woodiness and life history, for nearly all (&gt;99%) accepted taxon concepts included in the Australian Plant Census (APC). This dataset is predominantly derived from Australia’s state and national floras, supplemented by the taxonomic literature and diverse web resources. In total, 29,993 species and infraspecific taxa were scored for plant growth form, 30,279 for woodiness and 30,056 for life history, with taxa scored as displaying a single or multiple trait values, as appropriate. We provide sample R code that shows how to access and interrogate the dataset. This resource will enable rapid assessment of plant responses to disturbance events and new biogeographic analyses of trait distributions, better understandings of evolutionary trajectories, and ecological strategies.

Exploring the Anti-Inflammatory Potential of Australian Native Plants Based on their Ethnopharmacological Knowledge.

Inflammation represents the inherent protective reaction of the human body to various harmful agents and noxious stimuli. Standard anti-inflammatory therapy including nonsteroidal anti-inflammatory drugs are associated with several side effects. In the past decades, people rely on medicinal plants for the treatment of inflammation. The traditional utilization of medicinal plants is regarded as a safe, cost-effective, and broadly accepted approach. In this study, anti-inflammatory activity of plants traditionally utilized by the D'harawal people in Australia has been assessed in vitro. Eighty Australian native plants were screened based on the Dharawal Pharmacopeia for their inhibitory effect on the nitric oxide (NO) production in lipopolysaccharides (LPS) and interferon (IFN)-γ stimulated RAW 264.7 murine macrophages for their anti-inflammatory activity. From the eighty ethanolic extracts screened, seventeen displayed potent NO inhibition with an IC50 recorded below 15 μg/mL. The aim of this review was to utilise the ethnopharmacological knowledge and to correlate the anti-inflammatory activity of the seventeen plants with either their known or unknown phytochemicals reported in the literature. In doing so, we have created a snapshot of Australian native plant candidates that warrant further chemical investigation associated with their anti-inflammatory activity.

Constraints of commercially available seed diversity in restoration: Implications for plant functional diversity

Societal Impact StatementLarge quantities of diverse native seeds are required to scale up global restoration efforts. However, it remains unclear for many ecosystems how the diversity of available seed in commercial stocks reflects the composition of the ecosystems where vegetation is being remade. This study highlights existing shortfalls in the diversity of seed presently available for use in restoration and identifies gaps in the seed supply chain while providing a new method for optimising species selection given these constraints. This work underscores how improved collaboration between stakeholders is required to strengthen the seed supply chain and help remake functionally diverse vegetation.Summary Restoration using native seed is frequently implemented to restore degraded ecosystems. However, it remains unclear how constraints on the diversity of germplasm available for use in restoration may limit the recovery of both species and plant functional diversity. Using a dataset of seed availability for Australia's major vegetation types, we explore variation in the diversity and breadth of functional traits (leaf mass per area, seed mass, plant height) for species where seed is available on commercial markets relative to unavailable. Using these data, we simulate theoretical seed mixes derived from two species pools: (1) constrained by the current market of commercially available seed, and (2) assuming all native species can be planted; then we compare differences in functional diversity (dispersion) as an exercise to explore possible limitations within the current seed supply. Seed from only 12% of Australian plant species (2992 species) is presently available for immediate purchase. Seed was more frequently available for trees and shrubs than for understorey species. Available species were on average taller, with thicker, longer‐lived leaves than unavailable species. Overall, functional dispersion was lower for seed mixes generated using available seed compared with those drawn from all species. Solutions are required to address seed shortfalls so that plantings are not only species rich but also functionally diverse. We develop two options: (1) quantifying and addressing gaps in the seed supply chain that currently limit the capacity for practitioners to restore diverse vegetation; and (2) applying a trait‐informed species‐selection method to plantings that maximises functional diversity using available seed.

Evaluating the risk to Australia’s flora from Phytophthora cinnamomi

Context Phytophthora cinnamomi Rands is a destructive pathogen of Australian native vegetation, often causing permanent damage to ecosystems and threatening the survival of rare, susceptible species. Despite that, much information about the effects of P. cinnamomi on plant species remains unpublished and the risk of extinction to most species is unknown. Aims We aimed to classify the risk of extinction from P. cinnamomi to Australian native plants. Methods We used available data and personal knowledge about P. cinnamomi effects on plants, spatial data on plant species distribution and habitat suitability of P. cinnamomi to assign an extinction-risk category of low, moderate, high or very high. Key results There are currently 65 plant species at a very high risk of extinction in Australia as a result of P. cinnamomi infection. The genera Andersonia, Banksia, Darwinia, Daviesia, Epacris, Gastrolobium, Grevillea, Hibbertia, Isopogon, Lambertia, Latrobea, Leucopogon, Phebalium and Styphelia have multiple species at a very high risk of extinction, most of which occur in south-western Western Australia. Conclusions The available data confirmed the high risk to the Australian flora from P. cinnamomi and identified species in plant families not previously known to be affected, highlighting data gaps (e.g. lack of knowledge about effects and risk in orchids and grasses). Implications Much more work is required to fully understand the risk from P. cinnamomi (and other Phytophthora species) to the Australian flora.