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Background and aims: Phosphorus (P) is an essential plant nutrient and integral for crop yield. However, plants adapted to P-impoverished environments, such as Hakea prostrata (Proteaceae), are often sensitive to P supplies that would be beneficial to other plants. The strategies for phosphate uptake and transport in P-sensitive species have received little attention. Methods: Using a recently-assembled transcriptome of H. prostrata, we identified 10 putative members of the PHOSPHATE TRANSPORTER1 (PHT1) gene family, which is responsible for inorganic phosphate (Pi) uptake and transport in plants. We examined plant growth, organ P concentrations and the transcript levels for the eight PHT1 members that were expressed in roots of H. prostrata at Pi supplies ranging from P-impoverished to P-excess. Key results: Hakea prostrata plants suppressed cluster root growth above ecologically-relevant Pi supplies, whilst non-cluster root mass ratios were constant. Root P concentrations increased with increasing Pi supply. Of the eight H. prostrata PHT1 genes tested, four had relatively high transcript amounts in young roots suggesting important roles in Pi uptake; however, a maximum five-fold difference in expression between P-impoverished and P-excess conditions indicated a low P-responsiveness for these genes. The HpPHT1;8 and HpPHT1;9 genes were paralogous to Pi-responsive Arabidopsis thaliana PHT1;8 and PHT1;9 orthologues involved in root-to-shoot translocation of P, but only HpPHT1;9 was P responsive. Conclusions: An attenuated ability of H. prostrata to regulate PHT1 expression in response to Pi supply is likely responsible for its low capacity to control P uptake and contributes to its high P sensitivity. [ABSTRACT FROM AUTHOR]

Context: Obligate-seeding woody plants with long reproductive maturity periods and no soil seed banks are threatened with decline as climate change drives more frequent and severe fires, such as the extensive 2019–2020 wildfires in south-eastern Australia. Aims: This study aimed to investigate the effects of fire intervals and severity on the persistence of one such species, Banksia cunninghamii (Hairpin Banksia), in temperate forests. Methods: We measured post-fire seedling recruitment of B. cunninghamii at 25 sites in Victoria, burned at various severities in the 2019–2020 wildfires and with differing prior fire intervals. A Bayesian framework was used to model the relationship between seedling numbers, fire severity and fire interval. A spatial analysis compared a species distribution model for B. cunninghamii with fire severity and fire intervals. Key results: There was a low chance of B. cunninghamii recruitment (<25%) at sites that either had burned eucalypt canopies or a preceding fire interval of less than 12 years. Sixty-seven percent of its distribution in the south-east of the state of Victoria was mapped as burned at high severity (burned eucalypt canopies) between 1998 and 2020, or burned at shorter than 12 year intervals between 1960 and 2020, although some B. cunninghamii populations will have persisted due to the patchiness of past burns. Conclusions: Banksia cunninghamii is vulnerable to local extinctions in the wildfire-affected areas if fires occur again before plants reach maturity, or if high fire severity destroys seeds. Implications: More frequent and severe wildfires mean that burn planning needs to consider the reproductive cycles of serotinous obligate-seeding plants. Populations of Banksia cunninghamii are declining as climate change drives more frequent, severe and widespread fires. Research on this species after south-eastern Australia's 2019–2020 wildfires found that plants are killed by fire, with a low chance of seedling regeneration where severe fires burned eucalypt canopies, or the previous fire was less than 12 years ago. Large areas are no longer likely to support Banksia cunninghamii , and management is needed to protect juvenile plants until they produce seed cones. Photograph by Annette Muir. [ABSTRACT FROM AUTHOR]

Numerous phosphorus (P)‐acquisition and ‐utilisation strategies have evolved in plants growing in severely P‐impoverished environments. Although these strategies have been well characterised for certain taxa, like Proteaceae, P‐poor habitats are characterised by a high biodiversity, and we know little about how species in other families cope with P scarcity. We compared the P‐acquisition and leaf P‐allocation strategies of Fabaceae and Myrtaceae with those of Proteaceae growing in the same severely P‐impoverished habitat. Myrtaceae and Fabaceae exhibited multiple P‐acquisition strategies: P‐mining by carboxylates or phosphatases, P uptake facilitated by carboxylate‐releasing neighbours, and dependence on the elevated soil P availability after fire. Surprisingly, not all species showed high photosynthetic P‐use efficiency (PPUE). Highly P‐efficient species showed positive correlations between PPUE and the proportion of metabolite P (enzyme substrates), and negative correlations between PPUE and phospholipids (cellular membranes) and nucleic acid P (mostly ribosomal RNA), while we found no correlations in less P‐efficient species. Overall, we found that Myrtaceae and Fabaceae used a wider range of strategies than Proteaceae to cope with P scarcity, at both the rhizosphere and leaf level. This knowledge is pivotal to better understand the mechanisms underlying plant survival in severely nutrient‐impoverished biodiverse ecosystems. SUMMARY STATEMENT: Rather than depending solely on mycorrhizal symbioses, Myrtaceae and Fabaceae showed multiple P‐acquisition strategies growing in severely P‐impoverished environments as did Proteaceae. High investment of metabolite P and low investment of nucleic acid P was associated with high P‐use efficiency. [ABSTRACT FROM AUTHOR]

Macadamia trees are potentially at risk of many diseases especially those caused by latent pathogens. The Botryosphaeriaceae and Diaporthaceae species are among the most important latent pathogens, with widespread distribution across many climate zones and regions. Due to many recent reports of branch dieback in macadamia trees in South Africa this study aimed to: (i) identify the causal fungal species; (ii) examine the aggressiveness of the species obtained; (iii) evaluate the reaction of macadamia cultivars against the most aggressive species; (iv) evaluate the effectiveness of fungicides on disease development and (v) understand pathogens distribution in nurseries as well as common woody plants surrounding macadamia orchards. The samples were collected from trees showing symptoms in 12 orchards and the obtained isolates were identified by DNA sequence data for the rDNA‐ITS and TEF1‐α loci. Seven Botryosphaeriaceae species (Diplodia eriobotryicola, D. pseudoseriata, Lasiodiplodia theobromae, L. pseudotheobromae, Neofusicoccum parvum, N. kwambonambiense and Pseudofusicoccum olivaceum) and two Diaporthaceae species (Diaporthe ilicicola and Di. macadamiae) were identified. While L. theobromae was the most aggressive species, it produced significantly shorter lesions on the cultivars A4 and Nelmak2 than on Beaumont when their tolerance and susceptibility were evaluated. Out of the 14 commercial tested fungicides in the laboratory, greenhouse and field, five fungicides were confirmed to be effective against L. theobromae. In the survey of pathogen distribution, one species of Diaporthaceae was found to be common between trees in orchards and those in the nursery, while three species of Botryosphaeriaceae were common between trees in orchards and surrounding trees. This study highlights the risks posed by Botryosphaeriaceae and Diaporthaceae species to the macadamia crop. The evaluation of cultivar tolerance and efficacy testing of fungicides provide valuable insights for disease management and mitigation strategies in macadamia orchards, emphasising the need for proactive measures in preserving tree health and productivity. [ABSTRACT FROM AUTHOR]

Fungal diseases of macadamia fruit in South Africa have the potential to cause notable economic damage in this rapidly growing industry. To improve our understanding of the species involved in husk rot in macadamia orchards, a survey was conducted over two consecutive growing seasons to identify Colletotrichum, Diaporthe and Calonectria spp. that are associated with husk rot-infected macadamia fruits, and to investigate the occurrence of these fungi in asymptomatic and symptomatic fruits at the four stages of fruit development. Of the 425 fungal isolates obtained from the survey, Colletotrichum and Diaporthe were the most frequently isolated genera confirming the important role that these causal agents play in the husk rot epidemics. The detection of Calonectria species was low, only from symptomatic fruits and limited to a few locations in the main macadamia-producing provinces in South Africa. Colletotrichum and Diaporthe species were detected throughout the season at different stages of fruit development and in both symptomatic and asymptomatic fruits. The study confirmed that three fungal pathogens cause husk rot of macadamia in South Africa, with Colletotrichum and Diaporthe species that may have a latent phase in macadamia fruit. Studies of the growth characteristics of the husk rot pathogens revealed varied optimal growth temperatures, which may influence their prevalence in the different provinces in South Africa where macadamia is grown. The significance of the varied prevalence and biology of the causal agents in husk rot epidemics are discussed, which may be helpful management strategies. [ABSTRACT FROM AUTHOR]

Root growth, nutrient uptake, and nutrient use efficiency of a plant is influenced by the nutrient availability in its growing environment. The aim of this study was to investigate the root morphology, nutrient uptake and use efficiency of Grevillea robusta grown in nitrogen (N)- and phosphorus (P)-limited conditions. A hydroponic experiment was conducted for three months in a glasshouse with four nutrient treatments; (i) N-deficient, (ii) P-deficient, (iii) N/P-deficient (co-limitation of N and P), and (iv) control (sufficient amounts of N, P, and other nutrients in the growth medium). The composition and the concentration of each nutrient in the control solution were custom-made based on the growth requirement of G. robusta. N and P concentration in nutrient-deficient media were maintained at 2 ppm. The impact of N- or P-deficiency and their co-limitation on cluster root formation, organ-specific dry matter and nutrient accumulation, N and P uptake and their use efficiencies were measured. P-deficient conditions produced the highest number of cluster roots (24 ± 4) which was comparatively lower than those of N- and N/P-deficient conditions indicating that P-deficiency is the primary factor influencing the formation of cluster roots in G. robusta. The use efficiency of N and P in biomass formation was significantly (p < 0.05) enhanced when their uptake was reduced in response to N- and P-limitation. The efficient internal use of P by G. robusta under N- and N/P-deficiency is indicated by the significant increase in P-remobilization efficiency under these nutrient-deficient conditions. [ABSTRACT FROM AUTHOR]

Summary: In severely phosphorus (P)‐impoverished environments, plants have evolved to use P very efficiently. Yet, it is unclear how P allocation in leaves contributes to their photosynthetic P‐use efficiency (PPUE) and position along the leaf economics spectrum (LES). We address this question in 10 species of Banksia and Hakea, two highly P‐efficient Proteaceae genera.We characterised traits in leaves of Banksia and Hakea associated with the LES: leaf mass per area, light‐saturated photosynthetic rates, P and nitrogen concentrations, and PPUE. We also determined leaf P partitioning to five biochemical fractions (lipid, nucleic acid, metabolite, inorganic and residual P) and their possible association with the LES.For both genera, PPUE was negatively correlated with fractional allocation of P to lipids, but positively correlated with that to metabolites. For Banksia only, PPUE was negatively correlated with residual P, highlighting a strategy contrasting to that of Hakea. Phosphorus‐allocation patterns significantly explained PPUE but were not linked to the resource acquisition vs resource conservation gradient defined by the LES.We conclude that distinct P‐allocation patterns enable species from different genera to achieve high PPUE and discuss the implications of different P investments. We surmise that different LES axes representing different ecological strategies coexist in extremely P‐impoverished environments. [ABSTRACT FROM AUTHOR]

Background: Spatial clumping of plants results in intense competition. Aims: We analysed the extent of clumping of Proteaceae seedlings across the Cape Floristic Region after fire. Methods: To demonstrate the extent of clumping in 23 species, we analysed the seedling and adult densities in 290 post-fire surveys each of 100 × 1 m2 plots using standard indices of clumping. Key results: We detected clumping of Cape Proteaceae seedlings, whereas parent plants were less clumped. The clumping is not due to limited safe sites for seedlings because the number of plots at a site with at least one seedling was positively related to the number of seedlings at the site. Sites with seedlings were enriched in nutrients relative to those without. Conclusions: The possible benefits of clumping are saturation of granivores and co-location of buried seeds with nutrient-rich patches of fire-derived ash and debris. A cause of clumping is seeds sticking together. Clumping, which is strongly intraspecific, has implications for trait evolution and the dominance of reseeders over resprouters. Strong clumping reduces the usefulness of the widely used seedling:parent index to determine whether fires were favourable or not. Implications: Clumping has implications for understanding seed dispersal distances, seedling versus adult traits, fire responses and demography. Seedlings of Cape Proteaceae tend to occur in clumps and these clumps thin out with time to produce adult stands that are less clumped. We analysed seedling and adult densities and discuss the implications for trait evolution and dominance of reseeders over resprouters of strongly intra-specific clumping. [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]

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Yield in many crops is affected by abscission during the early stages of fruitlet development. The reasons for fruitlet abscission are often unclear but they may include genetic factors because, in some crops, self-pollinated fruitlets are more likely to abscise than cross-pollinated fruitlets. Pollen parentage can also affect final fruit size and fruit quality. Here, we aimed to understand the effects of pollen parentage on fruitlet retention and nut quality in orchards of macadamia (Macadamia integrifolia Maiden & Betche). We identified the pollen parent of macadamia 'cultivar '816' embryos by analysing single nucleotide polymorphisms (SNPs) in their DNA using customised MassARRAY and Single Allele Base Extension Reaction (SABER) methods. This allowed us to determine the proportions of self-fertilised and cross-fertilised progeny during premature fruit drop at 6 weeks and 10 weeks after peak anthesis, as well as at nut maturity. We determined how pollen parentage affected nut-in-shell (NIS) mass, kernel mass, kernel recovery, and oil concentration. Macadamia trees retained cross-fertilised fruitlets rather than self-fertilised fruitlets. The percentage of progeny that were cross-fertilised increased from 6% at 6 weeks after peak anthesis to 97% at nut maturity, with each tree producing on average 22 self-fertilised nuts and 881 cross-fertilised nuts. Three of the four cross-pollen parents provided fruit with significantly higher NIS mass, kernel mass, or kernel recovery than the few remaining self-fertilised fruit. Fruit that were cross-fertilised by '842', 'A4', or 'A203' had 16–29% higher NIS mass and 24–44% higher kernel mass than self-fertilised fruit. Nuts that were cross-fertilised by 'A4' or 'A203' also had 5% or 6% higher kernel recovery, worth approximately $US460–540 more per ton for growers than self-fertilised nuts. The highly selective abscission of self-fertilised fruitlets and the lower nut quality of self-fertilised fruit highlight the critical importance of cross-pollination for macadamia productivity. [ABSTRACT FROM AUTHOR]

Threatened species in rainforests may be vulnerable to climate change, because of their potentially narrow thermal tolerances, small population sizes, restricted distributions and limited dispersal. We investigated the relative influence of potential climate change on the population viability of Triunia robusta (Proteaceae), an endangered rainforest shrub endemic to southeast Queensland, Australia. A spatially explicit, stochastic population model with seven stage classes was developed and linked with the species distribution model (SDM) to explore a variety of hypothetical climate change simulations over a 90‐year period from 2010 to 2100: (1) constant population dynamics, (2) changes in habitat distributions as trend in carrying capacity and (3) changes in habitat distributions, precipitation and temperature regime as relative change in seedling survival and fecundity. The results revealed high vulnerability of small populations to local extinction regardless of geographical location or climatic stressors, while some larger populations located in the southern end of the species distribution range showed persistence in‐situ. Triunia robusta was found to be sensitive to reduced precipitation and increased temperature, limiting the species reproductive activities and seedling establishment and reducing the overall abundance consequently. Integration of population models and SDM allowed for the evaluation of multiple climatic stressors that may affect habitat distributions and population dynamics of T. robusta and ultimately suggest potential implications for future conservation and management planning with respect to climate change. [ABSTRACT FROM AUTHOR]

Aim: Climate change influences species distribution in space and time, but predicting the overlap in the range of interacting species under different climate scenarios remains a challenge. Here, we explore how climate change influences shifts in species ranges among mutualists. Location: Cape Floristic Region (CFR), South Africa. Taxon: Proteaceae and Passeriformes. Methods: We used machine‐learning algorithms (random forest and boosted‐regression trees) and regression model (generalized additive models) to predict range shifts of 11 bird‐pollinated Proteaceae species, combined occurrence prediction of 71 bird‐pollinated Proteaceae and their two most important, endemic, pollinator bird species. We determined the degree of overlap in geographical ranges of nectar‐feeding birds and Proteaceae under different climate scenarios. Species ranges were projected to the years 2050 and 2070 using representative concentration pathways (RCP) 4.5 and 8.5 and three global climate models. Results: The majority of Proteaceae species in our model are predicted to experience range contractions, which ranged from 1% under 2050 RCP 4.5 CCSM4 to 79% under 2070 RCP 8.5 CNRM‐CM5 climate scenarios, leading to 55% and 62% range loss for Cape sugarbird and orange‐breasted sunbird, respectively, under extreme climate scenarios. Proteaceae species are predicted to experience least overlap with nectar‐feeding birds in the northern and eastern range under future climate scenarios. Main Conclusion: Climate change threatens species occupying the mountain range of the northern limit and other regions of the CFR. Reduced range overlap of mutualists may have significant implications for the reproduction and persistence of Proteaceae. We suggest active monitoring of Proteaceae populations in regions where species are predicted to lose their range, particularly so for threatened species with small ranges. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the facilitation effects of an aluminum (Al) hyperaccumulator species bearing cluster roots, Gevuina avellana, on the seedling growth and performance of an Al-intolerant and phosphorus (P)- deficient-sensitive plant, Vaccinium corymbosum. For this, seedlings of G. avellana and V. corymbosum were grown alone or together as follows: i) two G. avellana seedlings, ii) one G. avellana + one V. corymbosum and iii) two V. corymbosum, in soil supplemented with Al (as Al2(SO4)3) and in the control (without Al supplementation). We determined relative growth rate (RGR), photosynthetic rate, chlorophyll concentration, lipid peroxidation and Al and nutrient concentration [Nitrogen (N), P, potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), and sulfur (S)] in leaves and roots of both species. The results showed that, in general, G. avellana did not assist V. corymbosum to enhance its RGR nor reduce its Al uptake. However, G. avellana assisted V. corymbosum in enhanced N acquisition and, consequently, to increase its chlorophyll concentration and photosynthetic rate. Besides, V. corymbosum had lower lipid peroxidation in leaves when grown in the soil with high Al supplementation in association with G. avellana. Our results suggest a facilitating effect of G. avellana to V. corymbosum when grown in soils with high Al concentration, by enhancing chlorophyll concentrations and photosynthetic rate, and decreasing the oxidative damage to lipids. [ABSTRACT FROM AUTHOR]

Morphological variation is common within widely distributed plant species and often raises interesting taxonomic and evolutionary questions. We sampled eight typical inland populations and two coastal dwarf populations of Banksia occidentalis to assess whether the coastal variant warrants taxonomic recognition. Genomic (single nucleotide polymorphisms) and morphometric analyses were undertaken to assess the variation within and between variants. Genetically, the coastal populations were more closely related to geographically adjacent populations of the typical variant than they were to each other, indicating that each coastal population has originated independently. Morphologically, the coastal populations also did not represent a cohesive phenotypic group, with both falling outside the range of variation for the typical variant, but also not overlapping each other. Wide morphological, but not genomic, variation was identified along a coastal–inland transect. Combined, these data indicate that the morphological variation in these coastal populations is the result of parallel ecotype evolution from experiencing similar environmental conditions and does not represent the diversification of a distinct evolutionary lineage that would have warranted taxonomic recognition. Our study highlights the consequences of strong selection pressures in marginal environments and provides fascinating insight to the long evolutionary history of the flora in this ancient Australian landscape. [ABSTRACT FROM AUTHOR]

Background and Aims The prevailing view from the areocladogenesis of molecular phylogenies is that the iconic South African Cape Proteaceae (subfamily Proteoideae) arrived from Australia across the Indian Ocean during the Late Cretaceous (100–65 million years ago, Ma). Since fossil pollen indicates that the family probably arose in North-West Africa during the Early Cretaceous, an alternative view is that it migrated to the Cape from North-West-Central Africa. The plan therefore was to collate fossil pollen records throughout Africa to determine if they are consistent with an African (para-autochthonous) origin for the Cape Proteaceae, and to seek further support from other palaeo-disciplines. Methods We used palynology (identity, date and location of records), molecular phylogeny and chronogram preparation, biogeography of plate tectonics, and palaeo-atmospheric and ocean circulation models. Key Results Our collation of the rich assemblage of Proteaceae palynomorphs stretching back to 107 Ma (Triorites africaensis) in North-West Africa showed its progressive overland migration to the Cape by 75–65 Ma. No key palynomorphs recorded in Australia–Antarctica have morphological affinities with African fossils but specific clade assignment of the pre-Miocene records is not currently possible. The Cape Proteaceae encompass three molecular-based clades (tribes) whose most recent apparent ancestors are sisters to those in Australia. However, our chronogram shows that the major Adenanthos / Leucadendron -related clade, originating 54–34 Ma, would have 'arrived' too late as species with Proteaceae affinities were already present ~20 million years earlier. The Franklandia / Protea -related clade arose 118–81 Ma so its distinctive pollen should have been the foundation for the scores of palynomorphs recorded at 100–80 Ma, but it was not. Also, the prevailing winds and ocean currents trended away from South Africa rather than towards, as the 'out-of-Australia' hypothesis requires. Based on the evidence assembled here, we list three points favouring an Australian origin and nine against; four points favouring an Antarctic origin and seven against; and nine points favouring a North-West-Central African origin and three against. Conclusions We conclude that a gradual migration of the Proteaceae from North-West-Central Africa southeast→south→southwest to the Cape and its surroundings occurred via adaptation and speciation during the period 95–70 Ma. We caution that incorrect conclusions may be drawn from literal interpretations of molecular phylogenies that neglect the fossil record and do not recognize the possible confounding effects of selection under matched environments leading to parallel evolution and extinction of bona fide sister clades. [ABSTRACT FROM AUTHOR]

Background and aims: Hakea prostrata (Proteaceae) is a highly phosphorus-use-efficient plant native to southwest Australia. It maintains a high photosynthetic rate at low leaf phosphorus (P) and exhibits delayed leaf greening, a convergent adaptation that increases nutrient-use efficiency. This study aimed to provide broad physiological and gene expression profiles across leaf development, uncovering pathways leading from young leaves as nutrient sinks to mature leaves as low-nutrient, energy-transducing sources. Methods: To explore gene expression underlying delayed greening, we analysed a de novo transcriptome for H. prostrata across five stages of leaf development. Photosynthesis and respiration rates, and foliar pigment, P and nitrogen (N) concentrations were determined, including the division of P into five biochemical fractions. Key results: Transcripts encoding functions associated with leaf structure generally decreased in abundance across leaf development, concomitant with decreases in foliar concentrations of 85% for anthocyanins, 90% for P and 70% for N. The expression of genes associated with photosynthetic function increased during or after leaf expansion, in parallel with increases in photosynthetic pigments and activity, much later in leaf development than in species that do not have delayed greening. As leaves developed, transcript abundance for cytosolic and mitochondrial ribosomal proteins generally declined, whilst transcripts for chloroplast ribosomal proteins increased. Conclusions: There was a much longer temporal separation of leaf cell growth from chloroplast development in H. prostrata than is found in species that lack delayed greening. Transcriptome-guided analysis of leaf development in H. prostrata provided insight into delayed greening as a nutrient-saving strategy in severely phosphorus-impoverished landscapes. [ABSTRACT FROM AUTHOR]

Background and aims: Proteaceae are a prominent plant family in south-western Australia. Most Proteaceae are 'calcifuge', occurring exclusively on old phosphorus (P)-impoverished acidic soils, with a few 'soil-indifferent' species also found on young P-richer calcareous soils. Calcium (Ca)-enhanced P toxicity explains the calcifuge habit of Proteaceae. However, previous research has so far been focused exclusively on the roles of Ca and P in determining Proteaceae distribution, and consequently there is little knowledge on how other soil-based strategies influence this distribution. We aimed to study the effects of young calcareous soils on four soil-grown Proteaceae and assess differences between calcifuge and soil-indifferent Proteaceae to better understand their natural distribution. Methods: Two calcifuge and two soil-indifferent Proteaceae from south-western Australia were grown in six contrasting soils, including young calcareous, and old acidic soils. Results: When grown in calcareous soils all species showed root growth inhibition, micronutrient deficiency, Ca-enhanced P toxicity, and negative impacts on physiology. Calcifuge species were more sensitive to calcareous soils than soil-indifferent ones, although this varied between genera. Soil-indifferent species tended to produce more cluster roots, release more carboxylates per root mass, and allocate less Ca to their leaves, compared with calcifuges; they also had smaller seeds and were less sensitive to Ca-enhanced P toxicity. Conclusion: We surmise that a combination of these traits allows soil-indifferent species to tolerate calcareous soils. This study provides insight into how Proteaceae respond to young calcareous soils and how this influences their distribution. [ABSTRACT FROM AUTHOR]

Background and aims: In extremely low-phosphorus (P) environments, most Proteaceae exude carboxylates from cluster roots. These carboxylates mobilise inorganic P which leads to a relatively high leaf manganese concentration ([Mn]). However, we found that Adenanthos cygnorum (Proteaceae) in a low-P habitat did not invariably have a high leaf [Mn] in south-western Australia. We aimed to explore how A. cygnorum acquires P in severely P-impoverished habitats. Methods: We determined soil P concentrations and leaf [Mn] of A. cygnorum growing within 1 m and more than 10 m away from other large Proteaceae. We also grew plants in a glasshouse to determine its root carboxylate exudation and rhizosheath phosphatase activity. Results: Adenanthos cygnorum did not produce functional cluster roots. It depended on carboxylates released by a P-mobilising neighbour, Banksia attenuata (Proteaceae), to acquire P when growing in severely P-impoverished soil (< 8 mg P kg− 1 dry soil). In slightly less P-impoverished soil (> 11 mg P kg− 1 dry soil), phosphatases released by A. cygnorum hydrolysed sufficient organic P that was relatively mobile. Conclusion: The reliance on facilitation of P acquisition in A cygnorum depended strongly on location. We demonstrated the exudation of phosphatases, which mobilise inorganic P; this P was adequate for growth when there was sufficient organic P in soil. Facilitation of P acquisition by B. attenuata allowed A. cygnorum to extend its range into severely P-impoverished habitats where it cannot exist without facilitation. This knowledge provides a better understanding of the diversity of P-acquisition strategies in severely P-impoverished environments. [ABSTRACT FROM AUTHOR]

Background and Aims Soils in south-western Australia are severely phosphorus (P) impoverished, and plants in this region have evolved a variety of P-acquisition strategies. Phosphorus acquisition by Adenanthos cygnorum (Proteaceae) is facilitated by P-mobilizing neighbours which allows it to extend its range of habitats. However, we do not know if other Adenanthos species also exhibit a strategy based on facilitation for P acquisition in P-impoverished environments. Methods We collected leaf and soil samples of Adenanthos barbiger , A. cuneatus , A. meisneri, A. obovatus , A. sericeus and Adenanthos sp. Whicher Range (G.J. Keighery 9736) growing in their natural habitats at different locations within the severely P-limited megadiverse environment of south-western Australia. Hydroponic experiments were conducted to collect the carboxylates exuded by cluster roots. Pot experiments in soil were carried out to measure rhizosheath phosphatase activity. Key Results We found no evidence for facilitation of P uptake in any of the studied Adenanthos species. Like most Proteaceae, A. cuneatus , A. meisneri , A. obovatus , A. sericeus and Adenanthos sp. Whicher Range (G.J. Keighery 9736) expressed P-mining strategies, including the formation of cluster roots. Cluster roots of A. obovatus were less effective than those of the other four Adenanthos species. In contrast to what is known for most Proteaceae, we found no cluster roots for A. barbiger. This species probably expressed a post-fire P-acquisition strategy. All Adenanthos species used P highly efficiently for photosynthesis, like other Proteaceae in similar natural habitats. Conclusions Adenanthos is the first genus of Proteaceae found to express multiple P-acquisition strategies. The diversity of P-acquisition strategies in these Proteaceae, coupled with similarly diverse strategies in Fabaceae and Myrtaceae, demonstrates that caution is needed in making family- or genus-wide extrapolations about the strategies exhibited in severely P-impoverished megadiverse ecosystems. [ABSTRACT FROM AUTHOR]

Global fruit and nut yields are affected by shortfalls in pollinator populations, and pollen limitation is most prevalent among tropical, bee-pollinated and self-incompatible plants. Macadamia is a subtropical, bee-pollinated crop in which some cultivars have been found to be highly outcrossing. We aimed to determine the extent of outcrossing and its effects on nut quality across a wide range of international macadamia cultivars in three countries. We sampled fruit from 19 macadamia cultivars across 23 sites in Australia, Brazil and South Africa. We used genotype-by-sequencing and MassARRAY methods to assign paternity to individual fruit and we assessed pollen-parent effects on nut quality. Macadamia was highly outcrossing, producing 80–100% of fruit by cross-pollination, at 17 of the 23 sites. Mixed mating (41–72% outcrossing) was identified at five sites, and low outcrossing (10%) was identified in one cultivar at one site where it was isolated from other flowering macadamia trees. Outcrossed fruit often had significantly better quality than selfed fruit, with 1.61–3.39 g higher nut-in-shell mass, 0.53–1.55 g higher kernel mass, 3.3–6.4% higher kernel recovery, and 3.0–3.5% higher oil concentration. The differences in kernel recovery equated to differences in value of USD 433–841 per ton of nut-in-shell at prices of USD 3000 per ton. In summary, macadamia cultivars were mostly highly outcrossing, and outcrossed nuts often had higher quality than selfed nuts. Growers should consider interplanting different cultivars more closely and distributing bee hives more widely to maximise cross-pollination, produce high yields, and optimise nut quality. [ABSTRACT FROM AUTHOR]

Context. The Southwest Australian Floristic Region has exceptional plant evolutionary complexity for fire, nutrition and pollination traits. Aims. Our aim was to allocate pollination strategies to all vascular plants in this biodiversity hotspot by analysing existing and new data. Methods. Here we assigned a flower syndrome to ~8800 plants in this region, using floral traits and visitation records for insects, birds or mammals, which were well correlated. Key results. Specific insect relationships were most common (3383), especially with native bees (2410), including buzz pollination (450). Others were pollinated by wind (1054 plants), water (35) or had relatively unspecialised flowers visited by diverse insects (3026). Specific associations with flies (588) or butterflies and moths (165) were less common. Approximately 14% were primarily pollinated by birds (601) or birds and insects (583) - with much larger flowers (corresponding with bird bill lengths), and less insect-attracting colours (e.g. red or green). Nonflying mammals, especially honey possums, visit certain flowers along with birds. Pollination complexity peaked in the Myrtaceae (11% bird, 25% bird and insect), Fabaceae (2% bird, 46% bee, 2% buzz pollination) and Proteaceae (40% birds, 31% specific insects). Bird pollination also has multiple origins in the Ericaceae (8%), Haemodoraceae (20%), Rutaceae (16%), Pittosporaceae (14%) and Eremophila (45%). Extreme specialisations included secondary pollen presentation (1231), post-pollination colour change (72), mobile columns (310), explosive pollen release (137) and visual (209) or sexual (171) deception in orchids. Pollination trait complexity included >275 evolutionary transitions, especially from insects to birds (130), more specific insects (100), or wind (15). These followed similar morphological pathways within families but differed between them. Conclusions. This complexity appears to be globally unique, and peaks in highly speciose plant families with diversity centred in the region. Implications. This has ecological and genetic consequences, especially for rare flora management, ecosystem restoration and assessing plant vulnerability to habitat degradation, fire and climate change. [ABSTRACT FROM AUTHOR]

The Australian genus Isopogon (Proteaceae) consists of approximately 39 species, most of which occur in southwestern Australia, a region of considerable endemism and biodiversity. Unresolved taxonomic issues exist for two species complexes (nine suspected taxa) allied to I. spathulatus and I. polycephalus. There is uncertainty in how to delimit species in these two complexes due to unclear or overlapping morphological characters, although recognition of four phrase‐named taxa provide starting hypotheses for potential new taxa. We used a genomic approach (ddRAD) to generate SNPs for 146 samples from 32 populations across the two complexes to evaluate the genomic distinction of taxa and delimit species. We used an optimised ipyrad assembly of the sequenced libraries, followed by custom filtering of samples and SNPs for ordination, genetic structure, distance and concatenation and coalescent phylogenetic analyses. Population genetic and phylogenetic analyses consistently supported three geographically overlapping yet genomically distinct groups, two of which showed additional genomic divergence consistent with multiple distinct species. Existing morphological hypotheses were congruent with genomic groupings in some cases but discordant in others, where genomic admixture suggested existing taxa were conspecific. Evaluating morphological characters, geographic distribution and genomic distinction, we recognise five species and three subspecies from nine original taxa. We provide a key to species in the complexes and related taxa, updated descriptions for existing taxa, and describe two new species, I. elatus sp. nov. and I. pallidus sp. nov., and two new subspecies, I. spathulatus subsp. obovatus stat. nov. and I. spathulatus subsp. elongatus subsp. nov. [ABSTRACT FROM AUTHOR]

Tingid classification has been problematic since the recognition of the family. The exaggerated ornamentation of many tingids has caused confusion in morphology-based phylogenies due to convergence. Also, some genera, like Ulonemia , lack exaggerated structures and their diagnoses rely on reduced morphology, making identification difficult. The relationship between these genera is of great interest, as several species of Ulonemia have recently become pests of Macadamia , and several of these genera are found on other Proteaceae. We used 16S, COI , 18S, and 28S to determine genus-level relationships of Ulonemia and other Australian Tingidae using maximum likelihood (ML) and Bayesian inference. We also analysed a morphological dataset using maximum parsimony. The parsimony analysis yielded numerous morphological homoplasies, and most deep clades lacked support. The ML and Bayesian analyses had strong support and returned a paraphyletic Ulonemia with three strongly supported clades. Two new genera, Cercotingis gen. nov. and Proteatingis gen. nov. are erected and Ulonemia redescribed to account for the observed phylogenies. Three new species of Cercotingis (C. croajingolong sp. nov. C. namadgi sp. nov. and C. tasmaniensis sp. nov.) and four new species of Proteatingis (Pr. astibosetes sp. nov. Pr. howardi sp. nov. Pr. minuta sp. nov. and Pr. xouthos sp. nov.) are described, with keys to species of Cercotingis and Proteatingis. [ABSTRACT FROM AUTHOR]

Aims This study aimed to evaluate and describe the functional differences of cultivable bacteria and fungi inhabiting the leaves of Gevuina avellana Mol. (Proteaceae) in an urban area with high levels of air pollution and in a native forest in the southern Andes. Methods and results Phyllosphere microorganisms were isolated from the leaves of G. avellana , their plant growth-promoting capabilities were estimated along with their biocontrol potential and tolerance to metal(loid)s. Notably, plants from the urban area showed contrasting culturable leaf-associated microorganisms compared to those from the native area. The tolerance to metal(loid)s in bacteria range from 15 to 450 mg l−1 of metal(loid)s, while fungal strains showed tolerance from 15 to 625 mg l−1, being especially higher in the isolates from the urban area. Notably, the bacterial strain Curtobacterium flaccumfaciens and the fungal strain Cladosporium sp. exhibited several plant-growth-promoting properties along with the ability to inhibit the growth of phytopathogenic fungi. Conclusions Overall, our study provides evidence that culturable taxa in G. avellana leaves is directly influenced by the sampling area. This change is likely due to the presence of atmospheric pollutants and diverse microbial symbionts that can be horizontally acquired from the environment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Botanical Research Institute of Texas is the property of Journal of the Botanical Research Institute of Texas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of the Botanical Research Institute of Texas is the property of Journal of the Botanical Research Institute of Texas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent decades, natural plant-based foods have been increasingly used to improve human health due to unhealthy modern dietary patterns, such as the consumption of foods high in sugar and fat. Many indigenous species have been used by Aboriginal peoples for their food and therapeutic properties. Thus, it is important to understand the health-enhancing bioactive profile of Australian indigenous species. The Proteaceae family, such as the genera of Protea, Macadamia, and Grevillea, have been commercially used in the horticulture and food industries. Researchers have reported some findings about Persoonia species, one of the genera in the Proteaceae family. The aim of this review was to provide an overview of the family Proteaceae and the genus Persoonia, including distribution, traditional and commercial uses, phytochemicals, bioactive properties, potential opportunities, and challenges. In this review, bioactive compounds and their properties related to the health benefits of the Proteaceae family, particularly the Persoonia genus, were reviewed for potential applications in the food industry. [ABSTRACT FROM AUTHOR]

Banksia L.f., an iconic genus of the Proteaceae, is endemic to Australia, with its highest species richness and phylogenetic diversity (PD) in southwestern Western Australia. Analysis of the phylogenetic component of richness and endemism uncovered important patterns of Banksia evolutionary history that are not seen at the species level. We found that Banksia is significantly phylogenetically clustered in this region, likely due to recent evolutionary radiations. We also found significant concentrations of phylogenetic endemism in this region, both neoendemism (short, range‐restricted evolutionary branches) and paleoendemism (long, range‐restricted evolutionary branches). There is a striking northwest to southeast divide in phyloturnover in southwestern Western Australia. The majority of the variation in turnover patterns can be explained by environmental factors, with climate representing the largest covariate. This study adds to the growing body of evidence that indicates the importance of integrating phylogenetic and biodiversity data to inform conservation planning. [ABSTRACT FROM AUTHOR]

Southern Patagonia contains several Eocene fossiliferous deposits that have only been superficially explored and studied. One of these corresponds to the La Marcelina Formation with outcrops in the south-western slope of the Deseado Massif, Santa Cruz Province, Argentina. No detailed palynological studies have been performed so far in this unit. Here we estimate the age, palaeoenvironment, and climatic conditions based on the analysis of terrestrially derived spores, algae cysts, and pollen grains. The recovered association supports an Eocene age and concurs with a mixed flora, including Gondwanan and Neotropical elements, dominated by Podocarpaceae, Nothofagaceae, and Proteaceae, and that probably developed under a temperate and humid climate. Overall, these results expand our understanding of the composition of Eocene floras from the highest latitudes of South America, as well as provide new evidence of past paleoclimates for the area. [ABSTRACT FROM AUTHOR]

Well-preserved leaf fossils from the Middle Eocene Anglesea site in Victoria are assigned to a new species of Megahertzia (M. paleoamplexicaulis R.J.Carp. & Rozefelds), a genus of Proteaceae now represented by a single species, M. amplexicaulis A.S.George & B.Hyland, in the Wet Tropics rainforests of Queensland. Megahertzia -like cuticular remains also occur in the Eocene Mount Hotham assemblage of Victoria, and pollen closely conforming to Megahertzia (i.e. Proteacidites latrobensis W.K.Harris) occurs widely in Cenozoic sediments of Australia and in New Zealand. All these records add to other fossil evidence that many species of Australian rainforest Proteaceae are the last vestiges of formerly much more widespread lineages. The fossil leaves are near-identical in architecture and cuticular features to lobed leaves of M. amplexicaulis , including that they have small teeth, stomata in well-defined areoles, and fine cuticular striations. Moreover, where preserved, the leaf fossils show amplexicaul bases, a unique (apomorphic) trait of the extant species. The apparent absence at Anglesea of simple (unlobed) leaves in Megahertzia and two other taxa of fossil Proteaceae is discussed; this leaf type could have evolved convergently in response to forest canopy heat increase as Australia drifted towards the Equator. The World Heritage Queensland Wet Tropics support an amazing 15 endemic genera of the Gondwanan Proteaceae family, including Megahertzia from the Daintree rainforest. Megahertzia -like fossil leaves were first collected from the Anglesea coal mine (Victoria, 3000 km away!) over 30 years ago, but have never been described. New fossil studies show the sole living species of Megahertzia as the last vestige of a formerly much more widespread lineage, and underscore the imperative need for conserving Australia's unique rainforest biota. [ABSTRACT FROM AUTHOR]

Flower diseases threaten macadamia production, but there is a limited understanding of their aetiology. This study was undertaken to establish the ecology of the causal agents in commercial orchards in Australia. Raceme samples at different developmental stages were collected from 42 commercial macadamia orchards during the 2018–2020 flowering seasons. Morphological and molecular phylogenetic analyses of the isolates obtained from the samples with symptoms revealed that 16 fungal species, including two Botrytis spp., six Cladosporium spp., six Neopestalotiopsis spp. and two Pestalotiopsis spp., were associated with the flower blights. Twelve of the fungal species were identified as new records in macadamia. A comparison of the fungal genera showed that Neopestalotiopsis spp. (48%) and Cladosporium spp. (47%) were the most prevalent in the majority of macadamia production regions and were obtained from all four raceme developmental stages. The genus Botrytis was more commonly distributed (16%) in the production areas where humidity was high and was mostly isolated from the mature developmental raceme stages. Based on in planta infection assays under field conditions, the fungal pathogens varied in aggressiveness on macadamia racemes, with B. cinerea, B. macadamiae, C. cladosporioides, C. devikae, N. drenthii, N. macadamiae, N. maddoxii, N. vheenae, P. macadamiae and P. telopeae as the most aggressive and C. angulosum and C. proteacearum as the least aggressive. This study improves our understanding of the aetiology and distribution of the causal agents of flower blight complex in macadamia. [ABSTRACT FROM AUTHOR]

Dating back to the late Early Cretaceous, the macrofossil record of the iconic lotus family (Nelumbonaceae) is one of the oldest of flowering plants and suggests that their unmistakable leaves and nutlets embedded in large pitted receptacular fruits evolved relatively little in the 100 million years since their first known appearance. Here we describe a new fossil from the late Barremian/Aptian Crato Formation flora (NE Brazil) with both vegetative and reproductive structures, Notocyamus hydrophobus gen. nov. et sp. nov., which is now the oldest and most complete fossil record of Nelumbonaceae. In addition, it displays a unique mosaic of ancestral and derived macro- and micromorphological traits that has never been documented before in this family. This new Brazilian fossil-species also provides a rare illustration of the potential morphological and anatomical transitions experienced by Nelumbonaceae prior to a long period of relative stasis. Its potential plesiomorphic and apomorphic features shared with Proteaceae and Platanaceae not only fill a major morphological gap within Proteales but also provide new support for their unexpected relationships first suggested by molecular phylogenies. [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]

Morphologically variable species complexes can present significant challenges to conservation when taxonomic boundaries, and therefore conservation units, are ambiguous. In such cases, the definition of Evolutionarily Significant Units (ESUs) based on high-resolution genomic data can be an effective method to clarify genetic divergence and inform conservation actions. Here, we employ a population genomic approach using SNP data to delineate conservation units in a morphologically ambiguous plant species complex (Conospermum caeruleum; Proteaceae) from a global biodiversity hotspot. Over 200 individuals representing five subspecies and three informal morphological forms were sampled across a wide geographic range. Phylogenomic (ML tree and SplitsTree network) and population genomic (STRUCTURE, PCoA, FST) analyses resolved three divergent genetic groups that were incongruent with the current taxonomy, but consistent with geographic distribution. One ESU was comprised of three genetic subgroups, and these can be considered Management Units (MUs) to conserve population genetic structure and diversity. These MUs were surprisingly incongruent with the current subspecies-level taxonomy, but one MU was consistent with a recently documented morphological form, and all were consistent with ecogeographic distribution. We recommend a full taxonomic revision of the Conospermum genus based on a phylogenomic approach to assess any wider incongruence with morphology, and that conservation strategies should be informed by genetic data. Our study exemplifies the application of genomics to the conservation of a morphologically ambiguous species complex, enabling and enhancing the practical conservation of appropriate units of biodiversity. [ABSTRACT FROM AUTHOR]

Objective: Heliciopsis terminalis (Kurz.) Sleum (family Proteaceae) is distributed in India, Mianma, Thailand, Cambodia, Vietnam, and China. In Vietnamese traditional medicine, it is used as an antidote for detoxifying the liver and detoxifying alcohol, a contraceptive, and to treat infections. The purpose of this study is to determine the chemical constituents of the plant, as well as their in vitro hepatoprotective and antioxidant activities. Methods: The dried powdered sample was ultrasonically extracted with MeOH, and the extract was fractionated by various chromatographic methods, including high-performance liquid chromatography. The structures of the isolated compounds were identified by NMR, high-resolution electrospray ionization mass spectrometry, and CD spectral analysis, and then screened for their in vitro hepatoprotective and antioxidant activities. Results: One new phenolic glycoside, named helitermioside (1), and eight known compounds (2-9) were isolated from the trunk and branches of H terminalis. All of the isolates were reported from H terminalis for the first time. Compound 6 showed antioxidant activity in thiobarbituric acid reactive substances (TBARS) lipid peroxidation inhibition assays, with an IC50 value of 61.16 ± 1.17 µg/mL, compared to that of Trolox (positive control), IC50 = 7.06 ± 0.11 µg/mL. At a concentration of 100 µg/mL, none of the isolates exhibited hepatocellular protective activity. Conclusion: Nine phenolic compounds (1–9) were recorded from H terminalis. Of these, compound 1 was new. Compound 6 exhibited moderate antioxidant activity in TBARS lipid peroxidation inhibition assays, but none of the compounds exhibited hepatocellular protective activity against CCl4-induced toxicity. [ABSTRACT FROM AUTHOR]

Floral chemical defence strategies remain under-investigated, despite the significance of flowers to plant fitness. We used cyanogenic glycosides (CNglycs)—constitutive secondary metabolites that deter herbivores by releasing hydrogen cyanide, but also play other metabolic roles—to ask whether more apparent floral tissues and those most important for fitness are more defended as predicted by optimal defence theories, and what fine-scale CNglyc localisation reveals about function(s)? Florets of eleven species from the Proteaceae family were dissected to quantitatively compare the distribution of CNglycs within flowers and investigate whether distributions vary with other floral/plant traits. CNglycs were identified and their localisation in florets was revealed by matrix-assisted laser desorption ionisation mass spectrometry imaging (MALDI-MSI). We identified extremely high CNglyc content in floral tissues of several species (>1% CN), highly tissue-specific CNglyc distributions within florets, and substantial interspecific differences in content distributions, not all consistent with optimal defence hypotheses. Four patterns of within-flower CNglyc allocation were identified: greater tissue-specific allocations to (1) anthers, (2) pedicel (and gynophore), (3) pollen presenter, and (4) a more even distribution among tissues with higher content in pistils. Allocation patterns were not correlated with other floral traits (e.g. colour) or taxonomic relatedness. MALDI-MSI identified differential localisation of two tyrosine-derived CNglycs, demonstrating the importance of visualising metabolite localisation, with the diglycoside proteacin in vascular tissues, and monoglycoside dhurrin across floral tissues. High CNglyc content, and diverse, specific within-flower localisations indicate allocations are adaptive, highlighting the importance of further research into the ecological and metabolic roles of floral CNglycs. [ABSTRACT FROM AUTHOR]

A new species, Helicia danlagunzadii, from the mossy forest of the Mt. Mantalingahan Protected Landscape (MMPL) in southern Palawan, Philippines is described and illustrated. The new species is distinct from the other known species of Helicia in the Philippines because of its ramiflorous flowering, very short inflorescences (less than 4 cm), and yellow color. Helicia danlagunzadii is the sixth species of the genus recorded in the Philippines. Following the assessment criteria of IUCN, the species is assessed as Critically Endangered. [ABSTRACT FROM AUTHOR]

Background and aims: Proteaceae species strongly acidify their rhizosphere to increase soil phosphorus (P) availability, which also inadvertently increases the availability of other elements, such as manganese and rare earth elements (REE). This study aimed to investigate REE (hyper) accumulation in the Proteaceae genus Helicia from Queensland, Australia, from a systematic assessment of REE concentrations in herbarium specimens and verification with field collected samples. Methods: Herbarium X-ray fluorescence (XRF) scanning (using yttrium as a proxy for REEs) was undertaken on selected Helicia species (Proteaceae) at the Queensland Herbarium, followed by Inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis and field collection of H. glabriflora samples to confirm the XRF findings. Results: The herbarium XRF analysis revealed highly anomalous REE concentrations in some Helicia species, reaching ~ 1300 µg Y g-1 in H. australasica and H. glabriflora. The ICP-AES analysis of the herbarium specimens revealed total REE concentrations (REE) of up to 2300 µg g-1 in H. australasica and H. glabriflora, with relatively higher light REEs (~ 70%) and yttrium (~ 20%) concentrations, compared to heavy REEs (~ 10%). The field collected H. glabriflora material had relatively higher total REE concentrations in the mature leaves (~ 850 µg REE g-1) and stems (~ 675 µg REE g-1), compared to young leaves (~ 130 µg REE g-1), roots (~ 220 µg REE g-1) and soil (~ 90 µg REE g-1). Conclusion: The discovery of REE (hyper)accumulation in these Helicia species suggests that the Proteaceae family may host several other REE hyperaccumulators that are hitherto undiscovered. This calls for systematic assessment of the Proteaceae using the same approach as used in this study. The findings have potential implications for (i) discovery of REE hyperaccumulator plants, (ii) investigation of REE uptake and accumulation in plants and (iii) biogeochemical exploration of buried REE ore deposits. [ABSTRACT FROM AUTHOR]

Phosphite has been sprayed on threatened natural plant communities in southwestern Australia for the past 25 years to mitigate the impact of the globally widespread plant pathogen, Phytophthora cinnamomi. Of concern is that this may result in an increase in phosphorus concentrations in naturally nutrient deficient soils, causing the loss of plant species that are sensitive to increased phosphorus levels. The impact of aerial spraying phosphite on soil and Proteaceae species richness and abundance was measured at three sites within the Southeast Coastal Province of Western Australia. Healthy and diseased vegetation which had been sprayed with phosphite for 14–26 years was compared with nonsprayed healthy and diseased vegetation. Contrary to expectations, there was no evidence that spraying is doing harm to Proteaceae species at the three sites studied. Healthy‐nonsprayed and Healthy‐sprayed areas had generally similar levels of soil total P, and this was associated with similar values for Proteaceae species richness and abundance in these areas. Phosphite spraying of diseased vegetation benefited Proteaceae plant diversity and abundance by preventing the disappearance of some species. Given these results, it was recommended that phosphite spraying be continued as a management action for controlling Phytophthora cinnamomi while research into alternative solutions continues. [ABSTRACT FROM AUTHOR]

Taxonomic review of the monotypic Australian endemic lycaenid genus Cyprotides Tite, 1963, based on comparative evidence of adult and juvenile morphology and biology, indicates that it comprises three allopatric and ecologically distinct species: C. pallescens Tite, 1963 stat. rev., C. cyprotus (Olliff, 1886) and C. maculosussp. nov.Cyprotides cyprotus is considered to comprise three subspecies: C. cyprotus cyprotus (Olliff, 1886) in the Sydney Sandstone region; C. cyprotus lucidusssp. nov. in the semi‐arid zone of inland central New South Wales, north‐western Victoria, South Australia, and south‐western Western Australia; and C. cyprotus aridusssp. nov. in the arid zone of southern Northern Territory and Western Australia. In contrast, C. maculosussp. nov. appears to be a narrow‐range endemic, restricted to subalpine areas in south‐eastern Australia (~1100–1500 m asl). Information on the distribution, ecology and biology is reviewed and summarised for each of these five taxa, with additional data provided on the habitat and conservation status of C. maculosussp. nov., which is considered to be Endangered under IUCN Red List Criteria. All three species appear to be characterised by predominantly univoltine life cycles but with variable pupal diapause that may last up to 2–3 years, larval polymorphism, facultative associations with ants, pupal stridulation and rapid larval development involving only four instars. It is hypothesised that speciation within this genus has occurred recently, driven by reinforcement following secondary contact, leading to pre‐mating isolation and character displacement, resulting in divergent phenotypes. [ABSTRACT FROM AUTHOR]

Narrowly endemic species are particularly vulnerable to catastrophic events. Compared to widespread species, they may also be less capable of adapting to shifts in environmental pressures as a result of specialisation on a narrow range of local condition and limited ability to disperse. However, life-history traits, such as preferential outcrossing and high fecundity can maintain genetic diversity and evolutionary potential, and boost species resilience. The endangered Grevillea bedggoodiana (Enfield Grevillea) is an understorey shrub restricted to an area of ca. 150 km2 in south-eastern Australia with a legacy of large-scale anthropogenic disturbance. Prior to this study little was known about its biology and population structure. Here, its breeding system was assessed through a controlled pollination experiment at one of its central populations, and eight populations were sampled for genetic analysis with microsatellite markers. The species was found to be preferentially outcrossing, with no evidence of pollination limitation. In most populations, allelic richness, observed heterozygosity and gene diversity were high (Ar: 3.8–6.3; Ho: 0.45–0.65, He: 0.60 − 0.75). However, the inbreeding coefficients were significant in at least four populations, ranging from Fi -0.061 to 0.259 despite high outcrossing rates. Estimated reproductive rates varied among sampled populations but were independent of gene diversity and inbreeding. Despite its small geographic range, the species' populations showed moderate differentiation (AMOVA: FST = 0.123), which was largely attributable to isolation by distance. We interpret these results as suggesting that G. bedggoodiana is reproductively healthy and has maintained high levels of genetic diversity despite recent disturbance. [ABSTRACT FROM AUTHOR]

The taxonomy of three informally-named, conservation-listed subspecies of Lambertia orbifolia C.A.Gardner was assessed using genotypic data generated from microsatellites in concert with morphological information. They were found to warrant formal taxonomic recognition and individualised conservation management. Lambertia orbifolia subsp. vespera A.D.Webb, L.Monks & Wege, an Endangered taxon from the Scott River Plains, and L. orbifolia subsp. pecuniosa A.D. Webb, L.Monks & Wege, a recently discovered and apparently rare taxon from south-west of Bowelling, are newly described and comparative data are provided for L. orbifolia subsp. orbifolia, a Critically Endangered taxon found near Narrikup. A revised description of L. orbifolia is also provided. [ABSTRACT FROM AUTHOR]

Background: Sorocephalus imbricatus (Thunb.) R.Br. is a range-restricted species endemic to the Cape Floristic Region (CFR), South Africa. It is currently classified as Critically Endangered in accordance with the IUCN criteria. Like many other species endemic to the CFR, S. imbricatus is subjected to several major threats including habitat loss, habitat degradation and the impacts of invasive alien species. Sorocephalus imbricatus was recently identified as a species requiring improved representation in ex-situ collections. During field work undertaken to collect germplasm for this purpose, a concerning number of dead and dying plants were observed. Objectives: To determine the cause of rapid death of individuals in a remnant subpopulation of S. imbricatus. Method: A field visit to a subpopulation of the only extant population, Elandskloof, was conducted to examine the symptoms associated with S. imbricatus mortality, and to collect samples for isolation and identification of putative pathogens. Results: Dead and dying plants showed clear symptoms of root and collar rot, with Phytophthora cinnamomi Rands recovered from all samples. The collections highlighted the severe impact of P. cinnamomi on S. imbricatus, with the size of the subpopulation being reduced from 62 to 37 individuals (a 40% reduction) between October 2021 and May 2022. Conclusion: This study describes, for the first time, rapid mortality of the Critically Endangered Proteaceae species, S. imbricatus, likely caused by the invasive pathogen P. cinnamomi. This concerning discovery highlights the urgent need for greater recognition of the threat P. cinnamomi poses not only to S. imbricatus, but to the broader floristic diversity of the CFR. Importantly, it illustrates a need for a substantial body of work to be undertaken to address a significant lack of knowledge regarding the relative threat that P. cinnamomi poses to species of the CFR. [ABSTRACT FROM AUTHOR]

The range of larval host plants for Aphanasium australe (Boisduval) is expanded to include several species of Grevillea in the Sydney region. Adult A. australe were reared from several species of Grevillea, G. buxifolia (Sm.) R.Br., G. oleoides Sieber ex Schult. & Schult., G. sericea (Sm.) R.Br. and G. speciosa (Knight) McGill. An additional record for Hakea sericea Schrad. & J.C.Wendl. is provided. In Hakea, A. australe has been found to infest the stems and roots but in Grevillea, it appears to be confined to infestation of the root system. The only known larval host records for Aphanasium spp. are Hakea and Grevillea (Proteaceae). [ABSTRACT FROM AUTHOR]

The present review details in a first part the structures of secondary metabolites discovered in Proteaceae up to now. In a second part, biological activities of bis-5-alkylresorcinols, a typical group of metabolites from Proteaceae, and their cyclized analogues are summarized. The scientific data required to make the inventory were exclusively compiled from books and journals. Using the list of plant genus, the bibliographic references were collected from (i) The Dictionary of Natural Products (DNP) and (ii) SciFinder Chemical abstract services. More than 130 references were carefully analyzed to found about 327 secondary metabolites. The most important classes of metabolites in Proteaceae were found as phenol glycosides (31%), derivatives of 5-alkylresorcinols (30%) and tropane alkaloids (11%). [ABSTRACT FROM AUTHOR]

Ten phenolic constituents, including three new macrocyclic glycosides (1–3), a new phenolic glycoside (5), a new biphenyl glycoside (6), and five known compounds (4, 7–10), were isolated from a 70% MeOH extract of the leaves of Heliciopsis terminalis by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-guided molecular networking. The chemical structures of new compounds 1–3, 5 and 6 were established based on comprehensive spectroscopic data analysis, including 1D and 2D NMR and HRESIMS techniques. All isolated compounds (1–10) were evaluated for their stimulation of glucose uptake in differentiated 3T3-L1 adipocytes using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent glucose analog. Compounds 3, 6 and 8 showed stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells. Among them, compounds 3 and 6 activated the AMPK signaling pathway in differentiated C2C12 myoblasts. [ABSTRACT FROM AUTHOR]

Thousands of plants produce both extrafloral nectaries (EFNs) on their leaves and nutrient‐rich appendages on their diaspores (elaiosomes). Although their individual ecology is well‐known, any possible functional link between these structures has almost always been ignored. Here, we recognized their co‐presence in the shrub, Adenanthos cygnorum (Proteaceae), and studied their function and interaction. We observed that the same ants frequently visit both structures, seeds are attractive to vertebrate granivores but are released into a leafy cup from where they are harvested by ants and taken to their nests, from which seeds, lacking elaiosomes, germinate after fire. We showed that juvenile plants do not produce EFNs and are not visited by ants. We conclude that EFNs are not just an indirect adaptation to minimize herbivory via aggressive ant visitors (the role of a minority) but specifically enhance reproductive success in two ways: First, by inducing ants to visit the plant as a reliable food source throughout the year. Second, by promoting discovery of the seasonally available, elaiosome‐bearing seeds for transport to their nests (the majority of visitors), so avoiding the risk of granivory should seeds instead fall to the ground. Parasitoid wasps play a supporting role in controlling the main insect herbivore whose larvae devour the reproductive apices. Thus, the EFN‐elaiosome relationship has three components that enhance species fitness: foliage protection, seed transport, and granivore escape. A similar system has been described only once before (in an unrelated biome) and, consistent with the objectives of ecology as an integrative science, deserves wider study. [ABSTRACT FROM AUTHOR]

The South American temperate forests were subjected to drastic topographic and climatic changes during the Pliocene‐Pleistocene as a consequence of the Andean orogeny and glacial cycles. Such changes are common drivers of genetic structure and adaptation. Embothrium coccineum (Proteaceae) is an emblematic tree of the South American temperate forest (around 20°S of latitude) that has strongly been affected by topographic and climatic events. Previous studies have shown a marked genetic structure in this species, and distinct ecotypes have been described. Yet, little is known about their adaptive genetic responses. The main goal of this study was to investigate the effects of historical and contemporary landscape features affecting the genetic diversity and connectivity of E. coccineum throughout its current natural distribution. Using over 2000 single nucleotide polymorphisms (SNPs), we identified two genetic groups (a Northern and a Central‐Southern group) that diverged around 2.8 million years ago. The level of genetic structure was higher among populations within the Northern genetic group than within the Central‐Southern group. We propose that these differences in genetic structure may be due to differences in the assemblages of pollinators and in the evolutionary histories of the two genetic groups. Moreover, the data displayed a strong pattern of isolation by the environment in E. coccineum, suggesting that selection could have led to adaptive divergence among localities. We propose that in the Chilean temperate forest, the patterns of genetic variation in E. coccineum reflect both a Quaternary phylogenetic imprint and signatures of selection as a consequence of a strong environmental gradient. [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]