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Fungi in the genera Knoxdaviesia and Sporothrix dominate fungal communities within Protea flowerheads and seed cones (infructescences). Despite similar ecologies, they show strong host recurrence and often occupy the same individual infructescence. Differences in host chemistry explain their host consistency, but the factors that allow co-occupancy of multiple species within individual infructescences are unknown. Sporothrix splendens and K. proteae often grow on different senescent tissue types within infructescences of their P. repens host, indicating that substrate-related differences aid their co-occupancy. Sporothrix phasma and K. capensis grow on the same tissues of P. neriifolia suggesting neutral competitive abilities. Here we test the hypothesis that differences in host-tissues dictate competitive abilities of these fungi and explain their co-occupancy of this spatially restricted niche. Media were prepared from infructescence bases, bracts, seeds, or pollen presenters of P. neriifolia and P. repens. As expected, K. capensis was unable to grow on seeds whilst S. phasma could. As hypothesised, K. capensis and S. phasma had equal competitive abilities on pollen presenters, explaining their co-occupancy of this resource. Growth of K. proteae was significantly enhanced on pollen presenters while that of S. splendens was the same as the control. Knoxdavesia proteae grew significantly faster than S. splendens on all tissue types. Despite this, S. splendens was a superior competitor on all tissue types. For K. proteae to co-occupy infructescences with S. splendens for extended periods, it likely needs to colonize pollen presenters before the arrival of S. splendens and may consequently depend on different spore vectors.

Sporothrix and Knoxdaviesia fungi use pollinators to colonize Protea flowers at anthesis. These saprobes remain dominant in the nutrient-rich, fire-retardant Protea seed-cones (infructescences) for at least a year after flowering. We tested the hypothesis that they competitively exclude potentially detrimental fungi from infructescences during this time. We compared seed set and longevity of infructescences containing Sporothrix and Knoxdaviesia vs. those that contain 'contaminant' saprobes. Hereafter we evaluated their competitive abilities against the 'contaminant' saprobes. Infructescences devoid of Sporothrix and Knoxdaviesia were dominated by Penicillium cf. toxicarium, Cladosporium cf. cladosporoides and Fusarium cf. anthophilum. Sporothrix and Knoxdaviesia presence did not affect seed viability, but infructescences persisted longer than those colonised by 'contaminant' fungi. The 'contaminant' species were stronger competitors than Sporothrix and Knoxdaviesia. However, Sporothrix and Knoxdaviesia could defend captured space well against 'contaminant' species. This effect was enhanced when fungal taxa grew on media prepared from their usual Protea host species, clarifying their dominance and host consistency observed in the field. Sporothrix and Knoxdaviesia from Protea are therefore weak competitors against common saprobes, especially when growing on alternative hosts, and need to colonise flowers very early (before colonization by other fungi) to dominate in this environment. They may delay seed release from infructescences longer than if these are colonised by other saprobes, increasing chances of seed release to occur after fire, when conditions are more favourable for Protea recruitment.

The influence of invasive alien plants on plant community structure and above ground biomass in their novel range is poorly understood, as the magnitude and direction of these effects are often species and ecosystem specific. Here we compared community metrices of native plants and soil properties between study sites invaded by Hakea drupacea, uninvaded sites and cleared sites (sites formerly invaded by H. drupacea). A total of 129 plant species belonging to 75 genera were recorded across all study sites. Invasive Acacia saligna, A. longifolia, A. cyclops (Fabaceae) and Leptospermum laevigatum (Myrtaceae) co-occurred with H. drupacea in the invaded sites. Overall plant species richness, which constituted higher number of native plant species, was recorded in uninvaded sites compared to invaded and cleared sites. Plant species composition was similar between uninvaded and cleared sites, but species composition recorded in uninvaded and cleared sites were significantly different from species composition recorded at invaded sites. Litter depth was significantly higher in invaded sites compared to uninvaded and cleared sites. Hakea drupacea did not affect soil properties in invaded sites. Here we show that H. drupacea probably reduces the diversity of native plant species especially in invaded sites probably through the effect of litter production and canopy cover, pointing to a beneficial effect of removal of H. drupacea. We encourage active restoration of sites invaded by H. drupacea at early stages of invasion before the plants become established and suppress the growth of native species.

Pollination services are critical in entomophilous crops. Relationships between pollinator visits and fruit set and mass are complex and optimal strategies to improve pollination are poorly defined. We often do not understand what proportions of the crop result from self- or cross-pollination, how cross-pollination affects crop quality and how far cross-pollen is transported. We quantified proportions of self- and cross-paternity in nuts of the partially self-incompatible macadamia cultivar 816 at increasing distances from cross-pollen sources. We estimated the distance of effective pollen movement, evaluated how pollination by different parents affected nut size and nutritional quality, and assessed whether distance from a cross-pollen source determined proportions of cross-pollinated nuts, nut size and number of nuts harvested. Almost all nuts resulted from cross-pollination, even at 184 m (23 rows) from a cross-pollen source. The cross-pollen cultivars in closest proximity were usually the pollen parents. Cross-pollination increased nut size and altered kernel nutritional quality. The number of harvested nuts decreased with increasing distance from a cross-pollen source in one orchard. Nut size was generally not affected by distance from a cross-pollen source. Synthesis and applications. Macadamia nut production resulted almost entirely from cross-pollination. Crop production was dependent on across-orchard transport of cross pollen, sometimes over at least 184 m. This shows the importance of pollen genotype, not just pollen quantity, in ensuring an effective pollination service. The number of harvested nuts decreased at 24 m from a cross-pollen source, suggesting that different cultivars should be inter-planted more closely in macadamia orchards. We need to better understand pollinator behaviour, including what genotype of pollen the different flower visitors carry, and how far and in what direction they transport pollen across orchards, to optimise crop yield and quality.

Invasive alien plants often influence pollinator visitation to native plants when sharing pollinator guilds. It is of conservation concern when the invasive alien plant is characterized by floral resources that attract pollinators, thereby reducing the reproductive success of native species. This is well studied for insects, but whether the same is true for bird pollinators is largely unknown. We address this by considering the impact of an invasive alien plant (Banksia speciosa) on visitation rates of nectar-feeding bird pollinators to native Protea compacta in the Cape Floristic Region of South Africa. We determined bird pollinator visitation rate to B. speciosa and P. compacta over 21 h of observation at three sites. We also quantified how visitation rate influenced reproductive success of both study species through different breeding experiments. Sugarbird visitation to P. compacta was significantly lower in the presence of B. speciosa, while there was no effect for sunbirds as they mostly avoided B. speciosa. Protea compacta had higher nectar volumes and sucrose per flower than B. speciosa. Sucrose per hectare was higher in all P. compacta plots compared to B. speciosa. Neither study species is pollen limited and they are self-compatible to some extent. But pollinator visitation enhanced seed production in both species. We show here that the invasive alien B. speciosa flowers attract sugarbirds - but not sunbirds - away from native P. compacta. The long-term effect of reduced pollinator visitation may reduce the fitness of P. compacta, but the long-term demographic impact is unknown and would require further study.

The Endangered Macadamia jansenii (C.L. Gross & P.H. Western, 1992) was known only from one small populationand a reintroduction program was implemented from 2009 to increase the number of populations. Recently, new subpopulations were discovered. However, in 2019, fire directly affected M. jansenii and the surrounding habitat. This study aimed to examine the abundance and distribution of M. jansenii in the wild pre- and post-fire, as well as to assess the success of the reintroduction program and species population viability. We undertook genetic analysis, population viability analysis (PVA) and updated the existing habitat models. The known wild M. jansenii population increased in abundance from 59 in a single population to 200 individuals (including seedlings), across three subpopulations. Results from the post-fire survey suggest that 83% of the wild plants have survived, with many plants resprouting. The newly discovered subpopulations were within predicted suitable habitat in the Bulburin National Park. These subpopulations are genetically similar to the original known population. Novel alleles suggest the potential for more plants to be located. The reintroduction program successfully established 20 individuals. PVA results indicate that even with the effects of fire, the species is unlikely to become extinct in the next 150 years.

Accurate identification of the botanical components of honey can be used to establish its geographical provenance, while also providing insights into honeybee (Apis mellifera L.) diet and foraging preferences. DNA metabarcoding has been demonstrated as a robust method to identify plant species from pollen and pollen‐based products, including honey. We investigated the use of pollen metabarcoding to identify the floral sources and local foraging preferences of honeybees using 15 honey samples from six bioregions from eastern and western Australia. We used two plant metabarcoding markers, ITS2 and the trnL P6 loop. Both markers combined identified a total of 55 plant families, 67 genera, and 43 species. The trnL P6 loop marker provided significantly higher detection of taxa, detecting an average of 15.6 taxa per sample, compared to 4.6 with ITS2. Most honeys were dominated by Eucalyptus and other Myrtaceae species, with a few honeys dominated by Macadamia (Proteaceae) and Fabaceae. Metabarcoding detected the nominal primary source provided by beekeepers among the top five most abundant taxa for 85% of samples. We found that eastern and western honeys could be clearly differentiated by their floral composition, and clustered into bioregions with the trnL marker. Comparison with previous results obtained from melissopalynology shows that metabarcoding can detect similar numbers of plant families and genera, but provides significantly higher resolution at species level. Our results show that pollen DNA metabarcoding is a powerful and robust method for detecting honey provenance and examining the diet of honeybees. This is particularly relevant for hives foraging on the unique and diverse flora of the Australian continent, with the potential to be used as a novel monitoring tool for honeybee floral resources., We used pollen DNA metabarcoding to identify the botanical content of 15 honey samples from six Australian biogeographical regions. We sequenced ITS2 and trnL P6 loop, which in combination identified 55 plant families, 67 genera, and 43 species. The trnL marker was able to differentiate between eastern and western Australian honeys and cluster samples into biogeographical regions. ​

Processes driving the divergence of floral traits may be integral to the extraordinary richness of flowering plants and the assembly of diverse plant communities. Several models of pollinator-mediated floral evolution have been proposed; floral divergence may (i) be directly involved in driving speciation or may occur after speciation driven by (ii) drift or local adaptation in allopatry or (iii) negative interactions between species in sympatry. Here, we generate predictions for patterns of trait divergence and community assembly expected under these three models, and test these predictions in Hakea (Proteaceae), a diverse genus in the Southwest Australian biodiversity hotspot. We quantified functional richness for two key floral traits (pistil length and flower color), as well as phylogenetic distances between species, across ecological communities, and compared these to patterns generated from null models of community assembly. We also estimated the statistical relationship between rates of trait evolution and lineage diversification across the phylogeny. Patterns of community assembly suggest that flower color, but not floral phenology or morphology, or phylogenetic relatedness, is more divergent in communities than expected. Rates of lineage diversification and flower color evolution were negatively correlated across the phylogeny and rates of flower colour evolution were positively related to branching times. These results support a role for diversity-dependent species interactions driving floral divergence during the Hakea radiation, contributing to the development of the extraordinary species richness of southwest Australia., Evolution Letters, 5 (3)

Proteaceae are an ecologically distinctive family, with largest radiations in the sclerophyll vegetation types of Australia and South Africa. This brief paper comments on Hayes et al. (2021), who have mapped leaf phosphorus concentration on to the phylogenetic tree for the family. Considered across all seed plants worldwide, Proteaceae contribute most of the lowest leaf nitrogen (N) and phosphorus (P) concentrations known. Hayes et al. concluded that they have used low-phosphorus strategy from their origins ca. 100 My ago. Occasional excursions into higher leaf P have been relatively recent and have not produced many species. The family as a whole is an instance of phylogenetic niche conservatism. The conservatism arises not from trait inertia but from the intensity of competition in continental vegetation, giving Proteaceae competitive advantage within distinct niches and inhibiting them from radiating into other ways of life. When a distinct niche is concentrated into a single clade in this way, quantitative methods that test for replicate patterns across multiple clades will not detect strong signal. However, niche-conservative clades make important and distinctive contributions to the world’s ecology.

Plant species richness increases with declining soil phosphorus (P) availability, especially for Proteaceae in old infertile landscapes. This difference in richness might be attributed to faster diversification in lineages adapted to P-impoverished soils, i.e. species that possess specialised P-acquisition strategies, and have lower leaf P concentration ([P]) and higher seed [P]. Alternatively, a longer time for species accumulation might contribute to high species richness in low-P environments due to the geological stability of the landscapes in which they evolved. We assessed differences in diversification of Proteaceae in P-impoverished vs. nutrient-rich environments and whether these were linked to adaptations to P-impoverished soils. We explored mature leaf and seed [P] and investigated how these traits changed over the evolutionary history of the family, and within two species-rich genera (Banksia, Hakea). Faster diversification was correlated with lower leaf and higher seed [P] for species-rich genera across the Proteaceae. For Banksia and Hakea, diversification rates peaked at relatively low leaf [P], but not at the lowest leaf [P]. Ancestral state reconstructions indicated that low leaf [P] is a trait that was likely present in the early evolution of the Proteaceae, with recent transitions to higher leaf [P] across several species-poor rainforest genera. Diversification of Proteaceae correlated strongly with P-related traits. In an evolutionary context, functional cluster roots, low leaf [P] and high seed [P] were likely key innovations allowing diversification. Selection for low leaf [P] early in the evolutionary history of Proteaceae pre-adapted ancestors of this family to diversify into oligotrophic environments. We discuss how our findings are likely relevant for understanding diversification dynamics of other plant families that occur in P-impoverished environments.

Background and Aims Extreme drought conditions across the globe are impacting biodiversity, with serious implications for the persistence of native species. However, quantitative data on physiological tolerance are not available for diverse flora to inform conservation management. We quantified physiological resistance to cavitation in the diverse Hakea genus (Proteaceae) to test predictions based on climatic origin, life history and functional traits. Methods We sampled terminal branches of replicate plants of 16 species in a common garden. Xylem cavitation was induced in branches under varying water potentials (tension) in a centrifuge, and the tension generating 50 % loss of conductivity (stem P50) was characterized as a metric for cavitation resistance. The same branches were used to estimate plant functional traits, including wood density, specific leaf area and Huber value (sap flow area to leaf area ratio). Key Results There was significant variation in stem P50 among species, which was negatively associated with the species climate origin (rainfall and aridity). Cavitation resistance did not differ among life histories; however, a drought avoidance strategy with terete leaf form and greater Huber value may be important for species to colonize and persist in the arid biome. Conclusions This study highlights climate (rainfall and aridity), rather than life history and functional traits, as the key predictor of variation in cavitation resistance (stem P50). Rainfall for species origin was the best predictor of cavitation resistance, explaining variation in stem P50, which appears to be a major determinant of species distribution. This study also indicates that stem P50 is an adaptive trait, genetically determined, and hence reliable and robust for predicting species vulnerability to climate change. Our findings will contribute to future prediction of species vulnerability to drought and adaptive management under climate change.

Female plants not only flower but also produce resource-rich seeds, fruits, and cones. Thus, it is generally considered that female plants allocate more resources to sexual reproduction than male plants and that this allocation difference can explain vegetative dimorphism, such as greater leaf size in females. We found significant sexual vegetative differences in the dioecious and serotinous species, Aulax umbellata and A. cancellata. Plant height, annual branch length and canopy spread were greater in males whereas leaf size, branch thickness and branch number were greater in females. Sex ratios and basal stem area were, however, equal in the sexes. Equal sex ratios imply equal allocation to sexual reproduction and equal stem areas imply equal resource use and biomass, and thus allocation to vegetative growth. Given equal allocation to reproduction and resource use, we suggest that the vegetative dimorphism is driven by intra-male-competition to be more visually conspicuous to pollinators. This implies that plant architecture is both a vegetative and a reproductive trait.

Land clearing of habitat into smaller, isolated remnants is a major driver of plant and animal extinctions globally. In southeastern Australia, once widespread temperate savannas have been subjected to extensive land clearing since European settlement. Some small fragments have persisted, but declines in the dominant trees have been reported, with anecdotal observations of widespread recruitment bottlenecks and seed set failure. To test the hypothesis that populations of Banksia marginata are experiencing widespread recruitment bottlenecks, we examined tree size-class distribution and production of infructescences (cones) of 15 populations on the western plains of Victoria, Australia. We found no evidence of widespread recruitment bottlenecks or a failure to set seeds; most populations were recruiting, though we did find evidence of declining recruitment with population size, suggesting evidence of an Allee effect. The proportion of trees without cones varied between populations; three populations had large numbers of trees (> 40%) lacking mature fertile cones. Managers should focus on minimising threats to seedling survival and augment populations below 100 individuals to improve recruitment and maintain stand persistence in the landscape.

Significance Forecasts of global change impacts on biodiversity often assume that the current geographical distributions of species match their ecological niches. Here we examine this assumption using an extensive dataset of large-scale variation in demographic rates that enables us to quantify demography-based ecological niches of 26 plant species. Contrasting these niches with the species’ geographic distributions reveals that niche–distribution mismatches can be large and depend on key life-history traits: poorly dispersed species are absent from suitable sites, and species with high persistence ability are present in sites that are currently unsuitable for them. Such niche–distribution mismatches need to be accounted for to improve forecasts of biodiversity dynamics under environmental change., The ecological niche of a species describes the variation in population growth rates along environmental gradients that drives geographic range dynamics. Niches are thus central for understanding and forecasting species’ geographic distributions. However, theory predicts that migration limitation, source–sink dynamics, and time-lagged local extinction can cause mismatches between niches and geographic distributions. It is still unclear how relevant these niche–distribution mismatches are for biodiversity dynamics and how they depend on species life-history traits. This is mainly due to a lack of the comprehensive, range-wide demographic data needed to directly infer ecological niches for multiple species. Here we quantify niches from extensive demographic measurements along environmental gradients across the geographic ranges of 26 plant species (Proteaceae; South Africa). We then test whether life history explains variation in species’ niches and niche–distribution mismatches. Niches are generally wider for species with high seed dispersal or persistence abilities. Life-history traits also explain the considerable interspecific variation in niche–distribution mismatches: poorer dispersers are absent from larger parts of their potential geographic ranges, whereas species with higher persistence ability more frequently occupy environments outside their ecological niche. Our study thus identifies major demographic and functional determinants of species’ niches and geographic distributions. It highlights that the inference of ecological niches from geographical distributions is most problematic for poorly dispersed and highly persistent species. We conclude that the direct quantification of ecological niches from demographic responses to environmental variation is a crucial step toward a better predictive understanding of biodiversity dynamics under environmental change.

RESUMEN Se estudió la propagación por semillas y por estacas de Orites myrtoidea (“Radal enano”), un arbusto con potencial ornamental de la familia Proteaceae, nativo de Chile y Argentina. A partir de material recolectado en otoño en la cordillera de la comuna de Pinto, Región de Ñuble, se evaluó el efecto en la germinación de semillas de 4 niveles de estratificación húmeda a 10° C (0, 7, 14 y 21 días), más uno de ácido giberélico (250 ppm) como control positivo, y el porcentaje y grado de enraizamiento de estacas con 5 niveles de inmersión rápida en solución de Ácido Indol Butírico (AIB) (0, 1.000, 2.000, 3.000 y 4.000 ppm) y un nivel de AIB en formulación en polvo (1.500 ppm). Los mayores porcentajes de germinación se obtuvieron con estratificación por 21 días y con inmersión en ácido giberélico, 80 y 92%, respectivamente. En la propagación vegetativa el porcentaje de enraizamiento superó el 90% en todos los tratamientos, sin embargo, todas las estacas tratadas con AIB presentaron un enraizamiento moderado a abundante, superior al control, en el cual se obtuvo un enraizamiento escaso a moderado.

SummaryMacadamia, a recently domesticated expanding nut crop in the tropical and subtropical regions of the world, is one of the most economically important genera in the diverse and widely adapted Proteaceae family. All four species of Macadamia are rare in the wild with the most recently discovered, M. jansenii, being endangered. The M. jansenii genome has been used as a model for testing sequencing methods using a wide range of long read sequencing techniques. Here we report a chromosome level genome assembly, generated using a combination of Pacific Biosciences sequencing and Hi-C, comprising 14 pseudo-molecules, with a N50 of 58 Mb and a total 758 Mb genome assembly size of which 56% is repetitive. Completeness assessment revealed that the assembly covered 96.9% of the conserved single copy genes. Annotation predicted 31,591 protein coding genes and allowed the characterization of genes encoding biosynthesis of cyanogenic glycosides, fatty acid metabolism and anti-microbial proteins. Re-sequencing of seven other genotypes confirmed low diversity and low heterozygosity within this endangered species. Important morphological characteristics of this species such as small tree size and high kernel recovery suggest that M. jansenii is an important source of these commercial traits for breeding. As a member of a small group of families that are sister to the core eudicots, this high-quality genome also provides a key resource for evolutionary and comparative genomics studies.

The Jurien Bay dune chronosequence in south‐western Australia’s biodiversity hotspot comprises sites differing in nutrient availability, with phosphorus (P) availability declining strongly with increasing soil age. We have explored the exceptionally high photosynthetic P‐use efficiency (PPUE) of Proteaceae in this region, triggering the question what the PPUE of co‐occurring species in other families might be along the Jurien Bay chronosequence. We explored how traits associated with PPUE, photosynthetic nitrogen (N)‐use efficiency (PNUE) and leaf respiration might converge along the chronosequence, and whether Proteaceae and non‐Proteaceae species differ in leaf traits associated with nutrient use. Seven to 10 species were sampled at three sites differing in nutrient availability (ranging from N‐ to P‐limited). Measurements of leaf light‐saturated photosynthesis and dark respiration were integrated with measurements of total N and P concentration in both mature and senesced leaves, and leaf mass per unit area (LMA). Contrary to what is known for other chronosequences, rates of photosynthesis and respiration did not decrease with increasing soil age and LMA along the Jurien Bay chronosequence. However, they increased when expressed per unit leaf P. Both N and P were used much more efficiently for photosynthesis on nutrient‐poor sites, in both Proteaceae and non‐Proteaceae species. Proteaceae had the fastest rate of photosynthesis per unit leaf P, followed by species that preferentially allocate P to mesophyll cells, rather than epidermal cells. Synthesis. Our results show that with declining soil P availability, photosynthetic P‐use efficiency of all investigated species from different families increased. Plants growing on the oldest, most nutrient‐impoverished soils exhibited similar rates of CO₂ exchange as plants growing on more nutrient‐rich younger soils, and extraordinarily high photosynthetic P‐use efficiency. This indicates convergence in leaf traits related to photosynthetic nutrient use on severely P‐impoverished sites.

Habitat fragmentation affects landscape connectivity, the extent of which is influenced by the movement capacity of the vectors of seed and pollen dispersal for plants. Negative impacts of reduced connectivity can include reduced fecundity, increased inbreeding, genetic erosion and decreased long-term viability. These are issues for not only old (remnant) populations, but also new (restored) populations. We assessed reproductive and connective functionality within and among remnant and restored populations of a common tree, Banksia menziesii R.Br. (Proteaceae), in a fragmented urban landscape, utilising a genetic and graph theoretical approach. Adult trees and seed cohorts from five remnants and two restored populations were genotyped using microsatellite markers. Genetic variation and pollen dispersal were assessed using direct (paternity assignment) and indirect (pollination graphs and mating system characterisation) methods. Restored populations had greater allelic diversity (Ar = 8.08; 8.34) than remnant populations (Ar range = 6.49–7.41). Genetic differentiation was greater between restored and adjacent remnants (FST = 0.03 and 0.10) than all other pairwise comparisons of remnant populations (mean FST = 0.01 ± 0.01; n = 16 P = 0.001). All populations displayed low correlated paternity (rp = 0.06–0.16) with wide-ranging realised pollen dispersal distances (

PREMISE OF THE STUDY Plant traits are often associated with the environments in which they occur, but these associations often differ across spatial and phylogenetic scales. Here we study the relationship between microenvironment, microgeographical location, and traits within populations using co-occurring populations of two closely related evergreen shrubs in the genus Protea. METHODS We measured a suite of functional traits on 147 plants along a single steep mountainside where both species occur, and we used data-loggers and soil analyses to characterize the environment at 10 microsites spanning the elevational gradient. We used Bayesian path analyses to detect trait-environment relationships in the field for each species. We used complementary data from greenhouse grown seedlings derived from wild collected seed to determine whether associations detected in the field are the result of genetic differentiation. KEY RESULTS Microenvironmental variables differed substantially across our study site. We found strong evidence for six trait-environment associations, although these differed between species. We were unable to detect similar associations in greenhouse-grown seedlings. CONCLUSIONS Several leaf traits were associated with temperature and soil variation in the field, but the inability to detect these in the greenhouse suggests that differences in the field are not the result of genetic differentiation.

Phosphorus (P) fertilisers, made from rock phosphate, are used to attain high crop yields. However, rock phosphate is a finite resource and excessive P fertilisers pollute our environment, stressing the need for more P-efficient crops. Some Proteaceae have evolved in extremely P-impoverished environments. One of their adaptations is to curtail the abundance of ribosomal RNA, and thus protein, and tightly control the acquisition and assimilation of nitrogen (N) and sulfur. This differs fundamentally from plants that evolved in environments where N limits plant productivity, but is likely common in many species that evolved in P-impoverished landscapes. Here, we scrutinise the relevance of these responses towards developing P-efficient crops, focusing on plant species where 'P is in the driver's seat'.

Protea cynaroides (king protea) is a flowering plant that belongs to the Proteaceae family. This multi-stemmed shrub is the national flower of South Africa and has important economic and medicinal values. Traditionally, the main therapeutic benefits of this plant species include the treatment of cancer, bladder, and kidney ailments. There are very limited reports on the isolation of phytochemicals and their biological evaluation from P. cynaroides. In this study, the leaves of P. cynaroides were air-dried at room temperature, powdered, and extracted with 80% methanol followed by solvent fractionation (hexane, dichloromethane, ethyl acetate, and butanol). The ethyl acetate and butanol extracts were chromatographed and afforded four new (1–4) and four known (5–8) compounds, whose structures were characterized accordingly as 3,4-bis(4-hydroxybenzoyl)-1,5-anhydro-D-glucitol (1), 4-hydroxybenzoyl-1,5-anhydro-D-glucitol (2), 2-(hydroxymethyl)-4-oxo-4H-pyran-3-yl-6-O-benzoate-β-D-glucopyranoside (3), 3-hydroxy-7,8-dihydro-β-ionone 3-O-β-D-glucopyranoside (4), 4-hydroxybenzoic acid (5), 1,5-anhydro-D-glucitol (6), 3,4-dihydroxybenzoic acid (7), and 3-hydroxykojic acid (8). The structural elucidation of the isolated compounds was determined based on 1D and 2D NMR, FTIR, and HRMS spectroscopy, as well as compared with the available literature data. The tyrosinase inhibitory activities of the extracts and isolated compounds were also determined. According to the results, compounds 7 and 8 exhibited potent competitive tyrosinase inhibitory activity against L-tyrosine substrates with IC50 values of 0.8776 ± 0.012 and 0.7215 ± 0.090 µg/mL compared to the control (kojic acid, IC50 = 0.8347 ± 0.093), respectively. This study is the first chemical investigation of compounds 1–4 from a natural source and the first report of the biological evaluation of compounds 1–5 against the tyrosinase enzyme. The potent anti-tyrosinase activity exhibited by P. cynaroides constituents will support future exploration of the plant in the cosmetic field upon further biological and clinical investigations.

Grevillea hortiorum Olde, a species in the Triloba Group sensu Flora of Australia (2000), is here described for the first time. Its nearest relative is certainly also a member of the Triloba Group, based on shared morphological characters, and it may be related to Grevillea acrobotrya Meisn. Numerous morphological differences distinguish it, but it has not been tested phylogenetically. Subsequent to its initial discovery when it was thought to be rare, both its distribution and population have been greatly expanded, almost exclusively due to the efforts of its eponymous collectors. It was initially thought to be uncommonly associated with open wandoo woodland but later collections have been gathered in open heath as well. An interim key to the species is provided.

In pollination systems with a diverse community of floral visitors, qualitative and quantitative variations in pollination effectiveness can lead to a system in which higher effectiveness results from the synergetic contribution of multiple pollinators. By employing a series of field and laboratory experiments in the south Andes of Ecuador, we compared the effectiveness of hummingbirds and nocturnal mammals visiting Oreocallis grandiflora, an Andean member of the Proteaceae. Pollinator effectiveness was measured with a quantitative component that assessed visitation rates to inflorescences and number of contacted stigmas per visit, and with a qualitative component that counted the number of deposited pollen grains in stigmas. Effectiveness estimates were complemented with controlled pollination experiments that contrasted fruit and viable seed set among flowers exposed to either diurnal or nocturnal pollination, self-pollinated flowers, and a control group with flowers exposed to naturally occurring pollination. Four species of hummingbirds and two species of nocturnal mammals visited the flowers of O. grandiflora. Hummingbirds outperformed nocturnal mammals in the quantitative components of pollination, while mammals were more effective than hummingbirds in the qualitative component. Pollination success was higher for the control group than for the other treatments, while hummingbirds and mammals performed similarly. Our findings suggest a case of functional complementarity in pollination: hummingbirds’ quantitative effectiveness complements nocturnal mammals’ qualitative effectiveness. Furthermore, our study demonstrates that pollination success in plants can be greater when flowers are visited by the whole diversity of pollinators.

The diverse bacterial communities in and around plants provide important benefits, such as protection against pathogens and cycling of essential minerals through decomposition of moribund plant biomass. Biodiverse fynbos landscapes generally have limited deadwood habitats due to the absence of large trees and frequent fire. In this study, we determined the effect of a fire disturbance on the bacterial communities in a fynbos landscape dominated by the shrub Protea repens using 16S ribosomal RNA amplicon sequencing. The bacterial community composition in newly formed fruiting structures (infructescences) and soil at a recently burnt site was different from that in an unburnt site. Bacteria inhabiting P. repens infructescences were similar to well-known taxa from decomposing wood and litter. This suggests a putative role for these aboveground plant structures as reservoirs for postfire decomposer bacteria. The results imply that inordinately frequent fires, which are commonplace in the Anthropocene, are a significant disturbance to bacterial communities and could affect the diversity of potentially important microbes from these landscapes.

Understanding the timescales that shape spatial genetic structure is pivotal to ascertain the impact of habitat fragmentation on the genetic diversity and reproductive viability of long-lived plant populations. Combining genetic and ecological information with current and past fragmentation conditions allows the identification of the main drivers important in shaping population structure and declines in reproduction, which is crucial for informing conservation strategies. Using historic aerial photographs, we defined the past fragmentation conditions for the shrub Conospermum undulatum, a species now completely embedded in an urban area. We explored the impact of current and past conditions on its genetic layout and assessed the effects of genetic and environmental factors on its reproduction. The historically high structural connectivity was evident in the genetics of the species. Despite the current intense fragmentation, we found similar levels of genetic diversity across populations and a weak spatial genetic structure. Historical connectivity was negatively associated with genetic differentiation among populations and positively related to within-population genetic diversity. Variation partitioning of reproductive performance explained ~ 66% of the variance, showing significant influences for genetic (9%), environmental (15%), and combined (42%) fractions. Our study highlights the importance of considering the historical habitat dynamics when investigating fragmentation consequences in long-lived plants. A detailed characterization of fragmentation from 1953 has shown how low levels of genetic fixation are due to extensive gene flow through the non-fragmented landscape. Moreover, knowledge of the relationships between genetic and environmental variation and reproduction can help to implement effective conservation strategies, particularly in highly dynamic landscapes.

Protea caffra is used as a diarrhoeal remedy in South African herbal medicine, however, its pharmacological properties remain largely unknown. In the present study, extracts from different Protea caffra organs were screened against drug-sensitive and -resistant diarrhoeagenic pathogens using the microdilution assay (minimum inhibitory concentration, MIC). Twig extracts (70% methanol, MeOH) of the plant were purified and the resultant fractions screened for antibacterial properties (MIC). The chemical profiles of the fractions were determined by Gas Chromatography-Mass Spectrometry (GC-MS), while ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used to quantify the phenolic acids in the plant. The mutagenic properties of bioactive extracts were assessed using the Ames test. The extracts demonstrated weak-moderate antibacterial properties (MIC: 0.3–0.6 mg/mL). A cold ethyl acetate fraction of MeOH twig extract exhibited significant antibacterial properties (MIC = 0.078 mg/mL) against Enterococcus faecalis. The presence of antibacterial compounds (1-adamantane carboxylic acid, heptacosanol, levoglucosan, nonadecanol) in the plant was putatively confirmed based on GC-MS analysis. Furthermore, UHPLC-MS/MS analysis revealed varying concentrations of phenolic acids (0.08–374.55 µg/g DW). Based on the Ames test, the extracts were non-mutagenic thereby suggesting their safety. To a certain degree, the current study supports the traditional use of Protea caffra to manage diarrhoea among local communities in South Africa.

Recent studies on patterns of biological invasions in several plant families have confirmed general findings (e.g., taxa with larger native range sizes are more likely to become invasive; and taxa with longer residence time in new regions are more likely to naturalise) and highlighted some context-specific findings relevant for management (e.g., resistance to Phytophthora is a pre-requisite for successful naturalisation in Proteaceae). We explore these issues for the plant family Myrtaceae, specifically by contrasting taxa with fleshy fruits with those with dry fruits to develop hypotheses around the role of seed dispersal in the invasion process. To this end we: 1) compiled a comprehensive list of introduced Myrtaceae; 2) determined the degree of establishment of each species in its introduced range; 3) compared the distribution of native, introduced, and invasive ranges; 4) assessed traits associated with the degree of establishment; and 5) assessed the magnitude and types of impacts of invasive Myrtaceae. A slightly higher proportion of dry-fruited species have been introduced than fleshy-fruited species [170 out of 2257 (7.5%) vs. 236 out of 3741 (6.7%)], though the difference was not significant. However, introduced dry-fruited Myrtaceae have naturalised more frequently than fleshy-fruited taxa [90 out of 170 (53%) vs. 40 out of 236 (17%)], whereas naturalised dry-fruited taxa have become invasive at a lower rate [22 out of 90 (24%) vs. 18 out of 40 (46%)]. Invasions of fleshy-fruited taxa seem to be more common on islands. Although invasions by fleshy- and dry-fruited species had similar impact mechanisms and magnitudes, naturalised fleshy-fruited Myrtaceae are more likely to have impacts on islands than dry-fruited confamilials. Synthesis Fleshy- and dry-fruited taxa of Myrtaceae differ in rate of transition along the invasion continuum and where invasions and impacts occur. We speculate that seed dispersal abilities, lack of competitors, and the availability of areas suitable for germination might explain these differences.

Extreme drought conditions across the globe are impacting biodiversity with serious implications for the persistence of native species. However, quantitative data on drought tolerance is not available for diverse flora to inform conservation management. We quantified physiological drought tolerance in the diverse Hakea genus (Proteaceae) to test predictions based on climatic-origin, life history and functional traits. We sampled terminal branches of replicate plants of 16 species in a common garden. Xylem cavitation was induced in branches under varying water potential (tension) in a centrifuge and the tension generating 50% loss of conductivity (stem P50) was characterized as a metric for drought tolerance. The same branches were used to estimate plant functional traits, including wood density, specific leaf area, and Huber value (sap flow area to leaf area ratio). There was significant variation in stem P50 among species, which was negatively associated with the species climate-origin (rainfall and aridity). Drought tolerance did not differ among life histories; however, a drought avoidance strategy with terete leaf form and greater Huber value may be important for species to colonize and persist in the arid biome. Our findings will contribute to future prediction of species vulnerability to drought and adaptive management under climate change.

The female of Xiphodontus endroedyi Bartolozzi, 2005 is described for the first time. The new locality record for this species shows that it actually has a wide distribution range across the Cape Floral Region, in the Fynbos Biome. Both larvae and adults were found boring into dead wood at the base of senescent trunks of a variety of Proteaceae species, including the alien invasive Hakea sericea., Fragmenta Entomologica, Vol. 51 No. 2 (2019)

Automeris zozine (Druce) is a silk moth in the family Saturniidae whose larvae typically defoliate plants in the Fagaceae, Fabaceae, and Anacardiaceae families, but little is known about other host plants. We documented the species defoliating Macadamia integrifolia Maiden and Betche (Proteaceae) associated with a plantation of coffee (Coffea spp., Rubiaceae) in a mountainous mesophyll forest at Veracruz, Mexico.

International audience; Organisms have evolved a diversity of life-history strategies to cope with variation in their environment. Persistence as adults and/or seeds across recruitment events allows species to dampen the effects of environmental fluctuations. The evolution of life cycles with overlapping generations should thus permit the colonization of environments with uncertain recruitment. We tested this hypothesis in Leucadendron (Proteaceae), a genus with high functional diversity native to fire-prone habitats in the South African fynbos. We analyzed the joint evolution of life-history traits (adult survival and seed-bank strategies) and ecological niches (climate and fire regime), using comparative methods and accounting for various sources of uncertainty. In the fynbos, species with canopy seed banks that are unable to survive fire as adults display nonoverlapping generations. In contrast, resprouters with an underground seed bank may be less threatened by extreme climatic events and fire intervals, given their iteroparity and long-lasting seed bank. Life cycles with nonoverlapping generations indeed jointly evolved with niches with less exposure to frost but not with those with less exposure to drought. Canopy seed banks jointly evolved with niches with more predictable fire return, compared to underground seed banks. The evolution of extraordinary functional diversity among fynbos plants thus reflects, at least in part, the diversity of both climates and fire regimes in this region.

Evolutionary radiations are responsible for much of Earth's diversity, yet the causes of these radiations are often elusive. Determining the relative roles of adaptation and geographic isolation in diversification is vital to understanding the causes of any radiation, and whether a radiation may be labeled as “adaptive” or not. Across many groups of plants, trait–climate relationships suggest that traits are an important indicator of how plants adapt to different climates. In particular, analyses of plant functional traits in global databases suggest that there is an “economics spectrum” along which combinations of functional traits covary along a fast–slow continuum. We examine evolutionary associations among traits and between trait and climate variables on a strongly supported phylogeny in the iconic plant genus Protea to identify correlated evolution of functional traits and the climatic‐niches that species occupy. Results indicate that trait diversification in Protea has climate associations along two axes of variation: correlated evolution of plant size with temperature and leaf investment with rainfall. Evidence suggests that traits and climatic‐niches evolve in similar ways, although some of these associations are inconsistent with global patterns on a broader phylogenetic scale. When combined with previous experimental work suggesting that trait–climate associations are adaptive in Protea, the results presented here suggest that trait diversification in this radiation is adaptive.