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Fire-prone landscapes experience frequent fires, disrupting above-ground biomass and altering below-ground soil nutrient availability. Augmentation of leaf nutrients or leaf water balance can both reduce limitations to photosynthesis and facilitate post-fire recovery in plants. These modes of fire responses are often studied separately and hence are rarely compared. We hypothesized that under severe burning, woody plants of a coastal scrub ecosystem would have higher rates of photosynthesis (A net) than in unburned areas due to a transient release from leaf nutrient and water limitations, facilitating biomass recovery post-burn. To compare these fire recovery mechanisms in regrowing plants, we measured leaf gas exchange, leaf and soil N and P concentrations, and plant stomatal limitations in Australian native coastal scrub species across a burn sequence of sites at 1 year after severe fire, 7 years following a light controlled fire, and decades after any fire at North Head, Sydney, Australia. Recent burning stimulated increases in A net by 20% over unburned trees and across three tree species. These species showed increases in total leaf N and P as a result of burning of 28% and 50% for these macronutrients, respectively, across the three species. The boost in leaf nutrients and stimulated leaf biochemical capacity for photosynthesis, alongside species-specific stomatal conductance (g s) increases, together contributed to increased photosynthetic rates after burning compared with the long-unburned area. Photosynthetic stimulation after burning occurred due to increases in nutrient concentrations in leaves, particularly N, as well as stomatal opening for some species. The findings suggest that changes in species photosynthesis and growth with increased future fire intensity or frequency may be facilitated by changes in leaf physiology after burning. On this basis, species dominance during regrowth depends on nutrient and water availability during post-fire recovery. [ABSTRACT FROM AUTHOR]

Context: Phytophthora cinnamomi has been present in Two Peoples Bay Nature Reserve in Western Australia for decades, with impacts observed in susceptible plant communities. Aims: This study aimed to examine the past and present impact of P. cinnamomi on ecosystems. Methods: The distribution of P. cinnamomi was mapped 1983–1995 and reassessed in 2024. The long-term spread of the pathogen was measured. Plant densities were assessed, dry-weight biomass measured, and visits by avifauna quantified in infested and healthy vegetation. The persistence of chlamydospores was assessed. Key results: Mapping confirmed the widespread distribution of P. cinnamomi in the Reserve, with some areas mapped as disease-free up to 1995 now infested. Phytophthora dieback has spread in Banksia shrubland at an average of 1.5 m/year over a 33-year period. The density of species from the Proteaceae, Fabaceae, Ericaceae, and Hibbertia was significantly reduced; and the biomass of non-sedge species and visits by avifauna lower in infested compared with healthy Banksia shrubland. However, pockets of healthy habitat persist in infested areas and two highly susceptible Ericaceae (Leucopogon glabellus , Styphelia flavescens) were observed in high numbers in infested vegetation. Recovery of chlamydospores confirmed the persistence of the pathogen behind the dieback front. Conclusions: The impact of P. cinnamomi is long term and irreversible, however, some susceptible species may have mechanisms to ensure their persistence through prolific seed production. Implications: Protection of areas of healthy susceptible habitat from the introduction and spread of P. cinnamomi , the implementation of existing control measures and research into alternative measures continue to be a priority. Plant disease caused by the root pathogen Phytophthora cinnamomi has resulted in significant changes to susceptible plant communities in Two Peoples Bay Nature Reserve. The long history of the pathogen in the Reserve, with studies on disease distribution and impact dating from the 1980s, provides an opportunity to examine the past and present impact of P. cinnamomi on ecosystems. This article belongs to the Collection The Natural History of Two Peoples Bay Nature Reserve, Western Australia. [ABSTRACT FROM AUTHOR]

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. The magnitude of the extinction risk to Australia's flora from Phytophthora cinnamomi is poorly known. Using available data, we found that 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 because of this pathogen. As many as 269 plant species may be at a very high risk of extinction on the basis of phylogenetic patterns. Photographs by Keith McDougall. [ABSTRACT FROM AUTHOR]

Honeys produced by Apis mellifera from different flowering plants can vary widely in their characteristics. Some floral sources yield honeys with especially high antibacterial and/or antioxidant activity, which may be candidates for further evaluation as therapeutic agents. This study investigated 115 honeys harvested from three Western Australian coastal bioregions: the Swan coastal plain, Geraldton sandplains and Dampierland. Honeys were derived from a range of floral sources, including Agonis, Banksia, Calothamnus, Callistemon, Eucalyptus, Leptospermum and Melaleuca, and several multifloral honeys including wildflower honey were also included. HPTLC fingerprinting was used to analyse the phenolics fractions of all honeys and fingerprints were analysed to attempt to verify the floral source of each honey. Typical fingerprints were discernible for the four honeys derived from Agonis flexuosa, Banksia sessilis, Banksia menziesii and Calothamnus. Antibacterial and anti-oxidant activity was quantified for all honeys and showed that Calothamnus honeys had the highest activity for both, and also contained the highest levels of phenolics. Hydrogen peroxide, colour and water content were also determined. Data obtained for all 115 honeys were analysed by principal component analysis to investigate broad trends, and showed that colour, total phenolics and antioxidant activity correlated strongly, whereas antibacterial activity was not strongly correlated with any other factors. Data obtained for individual floral sources were analysed by one-way analysis of variance and revealed significant differences between some honey types, supporting the hypothesis that honeys derived from different floral sources vary in important characteristics such as antibacterial and antioxidant activity. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to evaluate the effects of storage and different temperatures on the antibacterial activity and physicochemical characteristics of several types of honey. Methods and results: Honeys stored for 16 weeks at 37 and 45◦C showed significant declines in antibacterial activity determined by minimum inhibitory concentrations, the loss of hydrogen peroxide, decreases in honey pH, and increases in honey colour, with changes most pronounced at 45◦C. In contrast, honeys stored for 16 weeks at ambient (∼22◦C) and cold (4, −20, and −80◦C) temperatures showed only minor changes. In a second set of 12 honeys stored for 16–32 months at ambient temperature and then 4◦C, honeys showed minor changes in antibacterial activity, increases in colour, and decreases in pH. For a third set of 17 honeys stored for five years at ambient temperature, the honeys showed almost complete loss of hydrogen peroxide and were all significantly darker in colour, but showed varied changes in antibacterial activity. Conclusions: Heat was detrimental to the antibacterial activity of honeys, as was long-term storage at ambient temperatures for some honeys but not others. [ABSTRACT FROM AUTHOR]

The frequency and intensity of drought events are predicted to increase because of climate change, threatening biodiversity and terrestrial ecosystems in many parts of the world. Drought has already led to declines in functionally important tree species, which are documented in dieback events, shifts in species distributions, local extinctions, and compromised ecosystem function. Understanding whether tree species possess the capacity to adapt to future drought conditions is a major conservation challenge. In this study, we assess the capacity of a functionally important plant species from south-eastern Australia (Banksia marginata, Proteaceae) to adapt to water-limited environments. A water-manipulated common garden experiment was used to test for phenotypic plasticity and genetic adaptation in seedlings sourced from seven provenances of contrasting climate-origins (wet and dry). We found evidence of local adaptation relating to plant growth investment strategies with populations from drier climate-origins showing greater growth in well-watered conditions. The results also revealed that environment drives variation in physiological (stomatal conductance, predawn and midday water potential) and structural traits (wood density, leaf dry matter content). Finally, these results indicate that traits are coordinated to optimize conservation of water under water-limited conditions and that trait coordination (phenotypic integration) does not constrain phenotypic plasticity. Overall, this study provides evidence for adaptive capacity relating to drought conditions in B. marginata, and a basis for predicting the response to climate change in this functionally important plant species. [ABSTRACT FROM AUTHOR]

The frequency and intensity of drought events are predicted to increase because of climate change, threatening biodiversity and terrestrial ecosystems in many parts of the world. Drought has already led to declines in functionally important tree species, which are documented in dieback events, shifts in species distributions, local extinctions, and compromised ecosystem function. Understanding whether tree species possess the capacity to adapt to future drought conditions is a major conservation challenge. In this study, we assess the capacity of a functionally important plant species from south-eastern Australia (Banksia marginata, Proteaceae) to adapt to water-limited environments. A water-manipulated common garden experiment was used to test for phenotypic plasticity and genetic adaptation in seedlings sourced from seven provenances of contrasting climate-origins (wet and dry). We found evidence of local adaptation relating to plant growth investment strategies with populations from drier climate-origins showing greater growth in well-watered conditions. The results also revealed that environment drives variation in physiological (stomatal conductance, predawn and midday water potential) and structural traits (wood density, leaf dry matter content). Finally, these results indicate that traits are coordinated to optimize conservation of water under water-limited conditions and that trait coordination (phenotypic integration) does not constrain phenotypic plasticity. Overall, this study provides evidence for adaptive capacity relating to drought conditions in B. marginata, and a basis for predicting the response to climate change in this functionally important plant species.

Context: As threatening processes continue to impact rare plant populations, the use of translocations is becoming increasingly frequent. The ultimate success of translocation, attaining long-term persistence, is determined by species' ability to reproduce, recruit, and maintain levels of genetic diversity that permits the capacity to adapt to environmental change. Aims: This study aimed to assess translocation success of Banksia brownii. Methods: We compared genetic diversity, reproductive output and aspects of the mating system of a translocated population with four reference wild populations. Key results: We found that the use of multiple source populations for the translocation resulted in levels of genetic diversity comparable to reference populations of high diversity. Reproductive output was highest in the translocated population and a positive relationship between plant size and number of flowers across all populations was evident. However, mating system analysis revealed a large difference in outcrossing rates between populations in different habitats despite common pollinators, with the translocated population having the highest rates of selfing. Conclusion: Whilst genetic diversity and reproductive output were comparable or higher in the translocated population than in the reference populations, assessing translocation outcomes by these measures alone can potentially mask the longer-term erosion of genetic diversity through unfavourable patterns of mating. Implications: We recommend using multiple metrics of reproductive, recruitment and genetic diversity to properly assess plant translocation success. Genetic diversity and the processes that maintain it are key considerations for translocation success. Here we compare genetic diversity, mating systems, pollination and reproductive output of a translocated population of Banksia brownii with wild populations. Genetic diversity and reproductive output were comparable or higher in the translocated population than in the reference populations indicating success, however the translocated population had the highest levels of selfing. As such we recommend incorporating both genetic monitoring and demographic assessment when evaluating translocation outcomes. Image: Rebecca Dillon. Photo credit: Rebecca Dillon. [ABSTRACT FROM AUTHOR]

Seed fungal endophytes play an important beneficial role in the formation of the seedling mycobiome and contribute to plant establishment, but can also occur as latent pathogens and saprotrophs. Current knowledge on the function and diversity of seed fungal endophytes has been gained through studies in agricultural systems whilst knowledge from natural systems is relatively less. We used two co-occurring species from the genus Banksia from four sites in Australia's Sydney Basin Bioregion to investigate the abundance and diversity of seed fungal endophyte communities present in natural ecosystem hosts. Based on results from culturing and DNA sequence analysis of multiple loci, we found that Banksia seeds house a diverse range of fungal endophyte species, that when assigned to functional guilds belonged to multiple trophic modes. Thirty-one of the fungal taxa identified had not been previously reported as endophytes. Amongst the 58 Operational Taxonomic Units identified, Leotiomycetes and Sordariomycetes were the dominant classes and Banksiamyces (Leotiomycetes) and Penicillium (Sordariomycetes) the dominant genera, with many of the species isolated recorded in the literature as having a limited distribution. The two Banksias shared few fungal endophyte species, which were not always present across all study sites. We revealed a 'hidden diversity' within seeds of Banksia from natural ecosystems and provided insights into the influence host species can have on the seed mycobiome. • Fifty-eight fungal taxa were isolated from Banksia ericifolia and B. serrata seed. • Thirty-one of the 58 seed fungi had not been recorded as seed endophytes previously. • Majority of isolated fungi were Banksiamyces and Penicillium. • Majority of seed fungi isolated were assigned as saprotrophs or multi-trophic ecologicalmodes. • The two Banksia species shared few fungal species, which were not always present across all study sites. [ABSTRACT FROM AUTHOR]

Premise: Understanding evolutionary history and classifying discrete units of organisms remain overwhelming tasks, and lags in this workload concomitantly impede an accurate documentation of biodiversity and conservation management. Rapid advances and improved accessibility of sensitive high‐throughput sequencing tools are fortunately quickening the resolution of morphological complexes and thereby improving the estimation of species diversity. The recently described and critically endangered Banksia vincentia is morphologically similar to the hairpin banksia complex (B. spinulosa s.l.), a group of eastern Australian flowering shrubs whose continuum of morphological diversity has been responsible for taxonomic controversy and possibly questionable conservation initiatives. Methods: To assist conservation while testing the current taxonomy of this group, we used high‐throughput sequencing to infer a population‐scale evolutionary scenario for a sample set that is comprehensive in its representation of morphological diversity and a 2500‐km distribution. Results: Banksia spinulosa s.l. represents two clades, each with an internal genetic structure shaped through historical separation by biogeographic barriers. This structure conflicts with the existing taxonomy for the group. Corroboration between phylogeny and population statistics aligns with the hypothesis that B. collina, B. neoanglica, and B. vincentia should not be classified as species. Conclusions: The pattern here supports how morphological diversity can be indicative of a locally expressed suite of traits rather than relationship. Oversplitting in the hairpin banksias is atypical since genomic analyses often reveal that species diversity is underestimated. However, we show that erring on overestimation can yield negative consequences, such as the disproportionate prioritization of a geographically anomalous population. [ABSTRACT FROM AUTHOR]

Serotinous plants that both release seed and resprout after fire are thought to be resistant to wildfires within the range of intensities that have been experienced up until now. However, the frequency and scale of intense wildfires is increasing under climate change. We studied annual flowering and fruit‐set in a large population of Banksia spinulosa plants in south‐eastern Australia from the early 1990s to 2006. The results led us to predict that there would be little recruitment from seedlings after the next fire but good resprouting from very long‐lived lignotubers. Our study population burned in the widespread, high‐intensity wildfires of December 2019, providing an opportunity to test the hypothesis. Most above‐ground stems and cones were reduced to ash, and only 15 cones (on 10 plants) remained after the fire. We found no seedlings in the 0.3 ha site that had initially contained over 350 adult plants. Little natural mortality had been observed pre‐fire, but by 5 months after the fire, nearly 25% of lignotubers had failed to resprout. We conclude that even common and widespread resprouting species will suffer population decline and reduced genetic diversity as high‐intensity fires become more extensive and frequent. [ABSTRACT FROM AUTHOR]

Context and aim: Stands of the critically endangered Banksia conferta in north-eastern New South Wales show low recruitment and were examined to elucidate whether pollinator absence or fire history best explained this. Methods: Motion-detection cameras were deployed at three sites to identify potential pollinators, and age structure within stands and past follicle production were assessed through tree measurements and follicle counts. Key results: In total, 691 fauna-triggered image sequences were recorded between June and December 2019. Six mammal and 10 bird species were detected, but only 10 of these were observed probing inflorescences. White-cheeked Honeyeater and Sugar Glider combined comprised 66% of all fauna interactions, and of all 400 Banksia probes, 45% were from White-cheeked Honeyeaters and 18% were by Sugar Gliders. Different size structures of B. conferta were evident at each site, consistent with older and younger populations post-fire. Significantly more Banksia individuals (5×) were present at the younger site, likely governing pollinator composition through interspecific competition within pollinator guilds, and past follicle production was also greater here. Conclusions: Pollinator absence is not the cause of low recruitment in this population, and current stand structure and follicle production reflect past fire history. The three sites differed in their dominant fauna foragers, suggesting that B. conferta is a pollinator-generalist. Birds appear to operate as the key pollinating species during the day but are replaced by small mammals at night. Follicle production is higher in younger post-fire plants. Implications: The absence of fire from older populations for over 55 years is of concern, and population decline seems likely without fire intervention. The critically endangered Banksia conferta, known in New South Wales from a single aging population in former production forests, has shown low seed production over recent years and is declining. Much of its habitat has remained unburnt for over 50 years, and it is unclear whether fire absence or low pollinator populations are driving this decline. Motion-detection cameras identified considerable pollinator activity, and when coupled with analysis of Banksia demography data, imply that fire is needed to replenish populations. [ABSTRACT FROM AUTHOR]

The cylindrical conflorescences of the Banksia spinulosa Sm complex have several different colour types, i.e., black, red, maroon, lemon, and yellow. It is unknown if colour variation is due to extrinsic factors, importantly soil pH. Recent morphological observations have indicated that style colour are not contiguous, so follow-up chemical and soil analysis was conducted to further characterize the colour difference with respect to putative taxa and abiotic factors. Conflorescences of all known colours were sampled from across the eastern Australian distribution of B. spinulosa , and the respective soils were sampled and analysed for pH and total nitrogen. Regression analyses of this data demonstrated that pH and nitrogen gave nil and limited predictability for style colour respectively, i.e., only the taxa with black styles demonstrated a correlation, which was to a soil with slightly higher nitrogen content (p < 0.05). Furthermore, differences of pH were more often between taxa with conflorescences of the same colour. For chemical characterisation, the coloured styles were removed from conflorescences, extracted, and analysed by liquid chromatography-mass spectrometry (HPLC-MS/MS-DAD). Ten anthocyanin and twelve flavonol monoglycosides were identified by mass spectral fragmentation patterns (MS1 and MS2) and retention times. The data demonstrates that style colour differences are caused by the concentration of anthocyanins and their specific chemistry. It remains to be determined if the differences of anthocyanin expression are caused by other abiotic factors, or if it is intrinsic to the respective taxon. [Display omitted] • Styles from flowers of Banksia demonstrate high anthocyanin/flavonoid diversity. • Diversity is within heterogeneous species aggregates. • Black styles are highly concentrated with several major anthocyanins/flavonoids. • Yellow styles contain flavonoids only. • The colour of flower was not related to pH. [ABSTRACT FROM AUTHOR]