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

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.

Two subfamilies of bee flies, Ecliminae and Lomatiinae, are first reported from China with the description of the following two new species: Lomatia shanguii sp. nov. and Thevenetimyia cingulata sp. nov. A key to the Chinese subfamilies of Bombyliidae and a key to the Palaearctic species of Thevenetimyia Bigot are also presented.

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.

We present a list of tree species of French Guiana, based on data collected from herbarium specimens and tree inventories, and verified against all available taxonomic literature to date. The list contains 1811 taxa representing 87 families and 421 genera, including 143 unnamed species which either may be species not previously recorded in French Guiana, or taxa new to Science. Original demographic data such as global abundance, local maximum frequency and geographic dispersion, are given for the 1293 species present in tree inventories. Our work has led to the recognition of certain taxonomic and nomenclatural novelties, including a new combination in Lecythis Loefl. (Lecythidaceae), several lectotypifications and new synonyms, as well as reinstatement of Sloanea acutiflora Uittien (Elaeocarpaceae), Eugenia sinemariensis Aubl. (Myrtaceae), and four species of Inga (Leguminosae). In addition, we provide the most comprehensive list available to date of corresponding vernacular names (4354 for 1157 species) in nine languages spoken in French Guiana: Palikur, Kali’na, Teko, Wayãpi, Wayana, Nengee tongo (Aluku/Ndjuka/Paramaka), Creole, French, and Brasilian Portuguese. The checklist is complemented by indexes of exsiccata, vernacular names and scientific names. The introductory part is available in French and English., Nous présentons une liste des espèces d’arbres de Guyane française, basée sur des données issues de spécimens d’herbiers et d’inventaires d’arbres. Les noms ont été vérifiés au regard de toute la littérature taxonomique disponible à ce jour. La liste contient 1811 taxons représentant 87 familles et 421 genres, dont 143 espèces non nommées qui peuvent être soit des espèces non répertoriées précédemment en Guyane française, soit des taxons nouveaux pour la Science. Des données démographiques originales telles que l’abondance globale, la fréquence maximale locale et la dispersion géographique, sont données pour les 1293 espèces présentes dans les inventaires d’arbres. Nos travaux ont conduit à la reconnaissance de quelques nouveautés taxonomiques et nomenclaturales, dont une nouvelle combinaison dans le genre Lecythis Loefl. (Lecythidaceae), plusieurs lectotypifications et nouveaux synonymes, ainsi que la réinstallation de Sloanea acutiflora Uittien (Elaeocarpaceae), d’Eugenia sinemariensis Aubl. (Myrtaceae), et de quatre espèces du genre Inga (Leguminosae). En outre, nous fournissons la liste la plus complète disponible à ce jour des noms vernaculaires correspondants (4354 pour 1157 espèces) dans neuf langues parlées en Guyane française : Palikur, Kali’na, Teko, Wayãpi, Wayana, Nengee tongo (Aluku/Ndjuka/Paramaka), Créole, Français, et Portugais du Brésil. Le catalogue est complété par des index des exsiccata, des noms vernaculaires et des noms scientifiques. La partie introductive est proposée en français et en anglais.

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.

As Proteaceae subfamily Proteoideae are richly represented in the Cape Floristic Region of southern Africa and in south-western Australia, it is a convenient group for comparative studies of evolution and adaptation of plants in widely separated areas with a Mediterranean-type climate. Although species of Proteoideae attract considerable attention of researchers, the structural diversity of wood in this group remains under-explored. The wood structure of 51 species of 14 African and Australian genera of Proteoideae (Proteaceae) has been studied. These taxa are uniform in their wood structure; the diversity patterns are more related to plant stature, climatic factors and fire-survival strategies than to the taxonomy or phylogeny of the subfamily. Increases in length and diameter of fibres and diameter of pits in fibre walls are associated with a shift from a semi-arid winter-dry climate to a milder climate with winter rainfall. These trends may imply the transition from non-conducting imperforate tracheary elements to conducting elements in Mediterranean-type climatic regions. This presumable gain of hydraulic function of imperforate tracheary elements could be explained by adaptation to freeze–thaw stress during the late Quaternary, at least in the Cape Region. Vessel grouping shows no correlations with climatic factors. The seeders have a higher vessel frequency and narrower and lower rays than sprouters. We hypothesize that the larger rays in overground stems of sprouters serve as the sites of epicormic buds that provide for resprouting after fire or other damage. The occurrence of sclerified cells and/or irregularly arranged (occasionally circular) tracheary elements in broad rays of some species are thought to be responses to excessive sucrose transport in secondary phloem.

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.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.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.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.

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.

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.

Pestalotiopsis blight and leaf spot in macadamia are caused by species of Pestalotiopsis and Neopestalotiopsis. Conidia produced by these pathogens are mostly dispersed by wind and rain splash and are the primary infecting propagules. Rapid detection and quantification of airborne conidia are essential to determine the seasonal dynamics of inoculum and critical infection periods in macadamia orchards. A quantitative PCR (qPCR) using a new primer pair and a hydrolysis probe was developed to detect and quantify airborne conidia of Pestalotiopsis and Neopestalotiopsis species. The amplification efficiency of the qPCR was 96.4% and the assay had a limit of detection of 400 fg of Pestalotiopsis/Neopestalotiopsis gDNA, which corresponds to approximately 10 conidia. The qPCR assay coupled with spore trapping was used to monitor airborne conidia dispersal under field conditions. The results showed that the assay is specific and sensitive for detecting and quantifying Pestalotiopsis/Neopestalotiopsis conidia in macadamia orchards. The detection and quantification of the pathogen inoculum will improve our understanding of disease epidemiology and the ability to manage these diseases in macadamia.

Protea caffra Meisn. subsp. kilimandscharica (Engl.) Chisumpa & Brummitt — Habit: Small tree or shrub. Habitat: UMF, HZ, AZ; 2 200–3 800 m. Distribution: IIIa. Voucher: Sirimon Track, near Old Moses Camp Site, Alt. 3 351 m, 8 Jan. 2014, SAJIT 001643 (HIB). References: Fries & Fries (1929), Schelpe (1951), Young & Peacock (1985), Brummitt & Marner (1993), Bussmann (1993, 1994, 2006), Beentje (1994)., Published as part of Zhou, Ya-Dong, Mwachala, Geoffrey, Hu, Guang-Wan & Wang, Qing-Feng, 2022, Annotated checklist of the vascular plants of Mount Kenya, East Africa, pp. 1-108 in Phytotaxa 546 (1) on page 42, DOI: 10.11646/phytotaxa.546.1.1, http://zenodo.org/record/6550464, {"references":["Fries, R. E. & Fries, T. C. E. (1929) Beitrage zur Kenntnis der Flora des Kenia, Mt. Aberdare und Mt. Elgon. XII. Notizblatt des Koniglichen Botanischen Gartens und Museums zu Berlin 10 (96): 594 - 621. https: // doi. org / 10.2307 / 3994784","Schelpe, E. A. C. L. E. (1951) The Pteridophyta of Mount Kenya. American Fern Journal 41 (3): 65 - 74. https: // doi. org / 10.2307 / 1545044","Young, T. P. & Peacock, M. M. (1985) Vegetative key to the alpine vascular plants of Mount Kenya. Journal of the East Africa National History Society & National Museum 75 (185): 1 - 9. https: // doi. org / 10.1111 / j. 1365 - 2028.2004.00514. x","Brummitt, R. K. & Marner, S. K. (1993) Proteaceae. In: Polhill, R. M. (Ed.) Flora of Tropical East Africa. A. A. Balkema, Rotterdam, 30 pp.","Bussmann, R. W. (1993) The forest of Mt. Kenya (Kenya): A phytosociological approach with special reference to ecological problems. Ph. D. Thesis, Eberhard Karls Universitat Tubingen, Tubingen, 119 pp.","Bussmann, R. W. (1994) The forest of Mt. Kenya (Kenya): Vegetation, ecology, destruction and management of a tropical mountain forest ecosystem. Ph. D. dissertation, Universitat Bayreuth Startseite, Bayreuth, 252 pp.","Bussmann, R. W. (2006) Vegetation zonation and nomenclature of African Mountains: An overview. Lyonia 11 (1): 41 - 46.","Beentje, H. J. (1994) Kenya trees, shrubs and lianas. National Museums of Kenya, Nairobi, 762 pp."]}

Aerangis luteoalba (Kraenzl.) Schltr. var. rhodosticta (Kraenzl.) J.Stewart — Habit: Herb. Habitat: LMWF; up to 2 400 m. Distribution: II. Voucher: East Mount Kenya Forest, Alt. 1 524–1 829 m, Battiscombe K692 (EA, K). References: Blundell (1987), Cribb (1989b), Stewart & Campbell (2003), Agnew (2013)., Published as part of Zhou, Ya-Dong, Mwachala, Geoffrey, Hu, Guang-Wan & Wang, Qing-Feng, 2022, Annotated checklist of the vascular plants of Mount Kenya, East Africa, pp. 1-108 in Phytotaxa 546 (1) on page 25, DOI: 10.11646/phytotaxa.546.1.1

Faurea arborea Engl. — Habit: Small tree or shrub. Habitat: LMDF; up to 3 100 m. Distribution: IIIa. Voucher: Naro Moru River Lodge, Alt. 2 208 m, 10 Apr. 1977, Patel & Patel 156 (EA). References: Fries & Fries (1929), Brummitt & Marner (1993), Bussmann (1993, 1994), Bussmann & Beck (1995a, 1998, 1999)., Published as part of Zhou, Ya-Dong, Mwachala, Geoffrey, Hu, Guang-Wan & Wang, Qing-Feng, 2022, Annotated checklist of the vascular plants of Mount Kenya, East Africa, pp. 1-108 in Phytotaxa 546 (1) on page 42, DOI: 10.11646/phytotaxa.546.1.1, http://zenodo.org/record/6550464, {"references":["Fries, R. E. & Fries, T. C. E. (1929) Beitrage zur Kenntnis der Flora des Kenia, Mt. Aberdare und Mt. Elgon. XII. Notizblatt des Koniglichen Botanischen Gartens und Museums zu Berlin 10 (96): 594 - 621. https: // doi. org / 10.2307 / 3994784","Brummitt, R. K. & Marner, S. K. (1993) Proteaceae. In: Polhill, R. M. (Ed.) Flora of Tropical East Africa. A. A. Balkema, Rotterdam, 30 pp.","Bussmann, R. W. (1993) The forest of Mt. Kenya (Kenya): A phytosociological approach with special reference to ecological problems. Ph. D. Thesis, Eberhard Karls Universitat Tubingen, Tubingen, 119 pp.","Bussmann, R. W. (1994) The forest of Mt. Kenya (Kenya): Vegetation, ecology, destruction and management of a tropical mountain forest ecosystem. Ph. D. dissertation, Universitat Bayreuth Startseite, Bayreuth, 252 pp.","Bussmann, R. W. & Beck, E. (1995 a) The forests of Mt. Kenya (Kenya), a phytosociological synopsis. Phytocoenologia 25 (4): 467 - 560. https: // doi. org / 10.1127 / phyto / 25 / 1995 / 467","Bussmann, R. W. & Beck, E. (1998) The plant communities of the forests of Mount Kenya - First phytosociological and ecological data. In: Ojany, F. F. (Ed.) African mountains and highlands - planning for sustainable use of mountain resources. United Nations University, Tokyo, pp. 96 - 107.","Bussmann, R. W. & Beck, E. (1999) Vegetation units of Mt. Kenya Forest Reserve: Comment. In: Bitok (Ed.) Vegetations-okologosche, ethnobotanische und faunistische Beitrage uber Aquatorial-Afrika. Bayreuther Forum Okologie 64. Bayreuther Forum Okologie, Bayreuth, pp. 17 - 28."]}

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.

Non-mycorrhizal species such as Banksia (Proteaceae) that depend on root exudates to acquire phosphorus (P) are prominent in south-western Australia, a biodiversity hotspot on severely P-impoverished soils. We investigated the consequences of an exudate-releasing P-mobilising strategy related to control of iron (Fe) acquisition in two Banksia species, B. attenuata R.Br. and B. laricina C. Gardner, that differ greatly in their geographical distribution and rarity. We undertook solution culture experiments to measure root-mediated Fe reduction (FeR) in non-cluster and cluster roots at four stages of cluster-root development, and whole root systems for plants grown at 2 to 300 μM Fe (as Fe-EDTA). As a positive control, we used Pisum sativum (cv. Dunn) to validate the FeR assay. Unlike typical Strategy I species, both Banksia species showed no significant variation in FeR, for either cluster or non-cluster roots, when grown at a wide range of Fe supply. For roots of different developmental stages, we measured a range for B. attenuata cluster roots of 0.13 ± 0.03 to 1.29 ± 0.14 μmol Fe3+ reduced g−1 FW h−1 and 0.56 ± 0.11 to 1.10 ± 0.24 μmol Fe3+ reduced g−1 FW h−1 in non-cluster roots. Similarly, for B. laricina cluster-roots, FeR ranged from 0.22 ± 0.07 to 1.21 ± 0.37 μmol Fe3+ reduced g−1 FW h−1, and in non-cluster roots from 0.56 ± 0.11 to 0.71 ± 0.08 μmol Fe3+ reduced g−1 FW h−1. We also observed only minor differences for whole-root system FeR, and even though B. attenuata showed signs of leaf Fe deficiency in the 2 μM Fe treatment, its FeR was the lowest of both species across all treatments at 0.079 ± 0.009 μmol Fe3+ reduced g−1 FW h−1, compared with the fastest rate of 0.20 ± 0.014 μmol Fe3+ reduced g−1 FW h−1 for B. laricina in the 28 μM Fe treatment. Taking plants through a pulse from low to high Fe, then back to low Fe supply did not elucidate any significant response in FeR. Although Fe acquisition is tightly controlled in the investigated Banksia species, such control is not based on regulation of FeR, which challenges the model that is commonly accepted for Strategy I species.

Nutrient-poor ecosystems globally exhibit high plant diversity. One mechanism enabling the co-existence of species in such ecosystems is facilitation among plants with contrasting nutrient-acquisition strategies. The ecophysiological processes underlying these interactions remain poorly understood. We hypothesized that root positioning plays a role between sympatric species in nutrient-poor vegetation. We investigated how the growth traits of the focal mycorrhizal non-cluster-rooted Hibbertia racemosa change when grown in proximity of non-mycorrhizal Banksia attenuata, which produces cluster roots that increase nutrient availability, compared with growth with conspecifics. Focal plants were placed in the centre of rhizoboxes, and biomass allocation, root system architecture, specific root length (SRL), and leaf nutrient concentration were assessed. When grown with B. attenuata, focal plants decreased root investment, increased root growth towards B. attenuata, and positioned their roots near B. attenuata cluster roots. SRL was greater, and the degree of localized root investment correlated positively with B. attenuata cluster-root biomass. Total nutrient contents in the focal individuals were greater when grown with B. attenuata. Focal plants directed their root growth towards the putatively facilitating neighbour's cluster roots, modifying root traits and investment. Preferential root positioning and root morphological traits play important roles in positive plant-plant interactions.

BACKGROUND AND AIMS: Phosphorus (P) and nitrogen (N) are essential nutrients that frequently limit primary productivity in terrestrial ecosystems. Efficient use of these nutrients is important for plants growing in nutrient-poor environments. Plants generally reduce foliar P concentration in response to low soil P availability. We aimed to assess ecophysiological mechanisms and adaptive strategies for efficient use of P in Banksia attenuata (Proteaceae), naturally occurring on deep sand, and B. sessilis, occurring on shallow sand over laterite or limestone, by comparing the allocation of P among foliar P fractions. METHODS: We carried out pot experiments with slow-growing B. attenuata, which resprouts after fire, and faster growing opportunistic B. sessilis, which is killed by fire, on substrates with different P availability using a randomized complete block design. We measured leaf P and N concentrations, photosynthesis, leaf mass per area, relative growth rate and P allocated to major biochemical fractions in B. attenuata and B. sessilis. KEY RESULTS: The two species had similarly low foliar total P concentrations, but distinct patterns of P allocation to P-containing fractions. The foliar total N concentration of B. sessilis was greater than that of B. attenuata on all substrates. The foliar total P and N concentrations in both species decreased with decreasing P availability. The relative growth rate of both species was positively correlated with concentrations of both foliar nucleic acid P and total N, but there was no correlation with other P fractions. Faster growing B. sessilis allocated more P to nucleic acids than B. attenuata did, but other fractions were similar. CONCLUSIONS: The nutrient allocation patterns in faster growing opportunistic B. sessilis and slower growing B. attenuata revealed different strategies in response to soil P availability which matched their contrasting growth strategy.

Twenty-one Grevillea species currently comprise the Triloba Group sensu Flora of Australia, or Group 1 sensu The Grevillea Book. All species except the transcontinental species G. anethifolia R.Br. are distributed in south-west Western Australia. Grevillea pieroniae Olde, herein described, is currently treated as Grevillea sp. Stirling Range (D.J. McGillivray 3488 & A.S. George) by the Western Australian Herbarium. It has some affinity with Grevillea anethifolia through shared possession of similar truncate-conical to cylindrical pollen-presenters. Grevillea pieroniae is a rare species that is potentially threatened by Phytophthora cinnamomi, fire frequency, a drying climate, as well as feral and native herbivore-grazing, so requires careful assessment and ongoing monitoring. A short history of the Triloba Group is provided to give context to Grevillea pieroniae and as precursor to other related species soon to be recognised.

Very few of the >650 Proteaceae species in south-western Australia cope with the high calcium (Ca) levels in young, calcareous soils (soil indifferent); most are Ca sensitive and occur on nutrient-impoverished, acidic soils (calcifuge). We assessed possible control points for Ca transport across roots of two soil-indifferent (Hakea prostrata and Banksia prionotes) and two calcifuge (H. incrassata and B. menziesii) Proteaceae. Using quantitative X-ray microanalysis, we investigated cell-specific elemental Ca concentrations at two positions behind the apex in relation to development of apoplastic barriers in roots of plants grown in nutrient solution with low or high Ca supply. In H. prostrata, Ca accumulated in outer cortical cells at 20 mm behind the apex, but [Ca] was low in other cell types. In H. incrassata, [Ca] was low in all cells. Accumulation of Ca in roots of H. prostrata corresponded to development of apoplastic barriers in the endodermis. We found similar [Ca] profiles in roots and similar [Ca] in leaves of two contrasting Banksia species. Soil-indifferent Hakea and Banksia species show different strategies to inhabit calcareous soils: H. prostrata intercepts Ca in roots, reducing transport to shoots, whereas B. prionotes allocates Ca to specific leaf cells.

Lomatia shanguii Yao, Li & Yang, sp. nov. (Figs 1, 2���4) Diagnosis. Wing darkly infuscated along veins, crossvein r-m nearly at 1/6 from apex of discal cell. Abdominal tergites anteriorly black with posterior band yellow. Epandrium irregular in shape, slightly wider than long in dorsal view; epiphallus elongate, with a very sharp apex in dorsal view, distiphallus spiny and slightly curved, acute at apex in lateral view. Description. Male (Fig 2). Body length 10.2 mm, wing length 13.4 mm. Head: black except frons above antennae brown, pollinosity on head white; ocellar tubercle black with long black hairs; ocelli brown; face with dense long and erect black hairs; sides of clypeus and areas surrounding antennae bases with much more dense long black hairs; dichoptic eyes; frons and face widened; occiput with sparse erect black hairs and a row of erect dark brown hairs on edge. Antenna black except for brown apex of flagellum; scape about 2�� longer than wide, with white pollinosity and long black hairs; pedicel nearly as long as wide, with golden yellow pollinosity and short black hairs; flagellum conical, with golden yellow pollinosity, almost bare, narrowed from base to 1/3 length, remaining 2/3, uniform in width except for sharply acute apex; antennal length ratio of scape:pedicel:flagellum = 3:1:6. Proboscis black with short yellow hairs; palpus black with long black hairs and brown pollinosity. Thorax: black with black and yellow hairs, black bristles and grey pollinosity; postpronotal lobe with long black and yellow hairs, scutum with dense long black and yellow hairs on anterior margin and lateral portion before base of wing, sparse erect black hairs and recumbent yellow hairs dorsally; postalar callus with three black bristles and dense long black and yellow hairs; mesonotum with sparse black and yellow hairs laterally and medially. Pleura with anepisternum, anatergite, katepisternum and katatergite with white pollinosity; anepisternum with long black hairs anterodorsally and dense long yellow hairs posteroventrally; scutellum black with long sparse black hairs and sparse yellow hairs dorsally and row of long black bristle-like hairs along posterior margin. Legs black with brown pollinosity, black hairs and bristles; coxae with long dense black hairs; fore femur with brown pollinosity and dense erect black hairs; mid and hind femora with dense long erect black hairs and recumbent black scales; fore tibia with dense short black hairs, and recumbent black scales; tarsi with short black hairs and recumbent black scales; mid tibia with nine ad, seven pd, eight av and five pv; hind tibia with 11 ad, 16 pd, nine av and 11 pv. Wing (Fig. 3): mostly infuscated, with dark infuscations along veins; crossvein r-m placed nearly at 1/6 from apex of discal cell; base of wing with tuft of long white hairs on Costal; halter mostly yellow except for brown margin of knob. Abdomen: black and yellow with black and yellow hairs; tergite 1 with anterior half black and posterior half yellow, with dense yellow hairs laterally and sparse yellow hairs medially; other tergites black with yellow band on posterior margins, with dense black hairs laterally and sparse black hairs and dense black scales medially; sternites 1���2 brown with long erect yellow hairs and short black hairs; other sternites black with dense long and erect black hairs and short black hairs. Male terminalia (Fig. 4): Epandrium subtriangular, with long black bristles apically, nearly as long as wide, and with distinct basal extension in lateral view; cercus exposed in lateral view; epandrium irregular in shape, slightly wider than long in dorsal view; gonocoxa with brush of black hairs on anterior half, subquadrate, nearly 3�� longer than wide, and slightly narrowed from base to apex in ventral view; gonostylus thick basally, apex obtuse, slightly narrowed from middle to apex in lateral view; epiphallus elongate, with a very sharp apex in dorsal view, distiphallus spiny and slightly curved, acute at apex in lateral view. Female. Body length: 21 mm; wing length: 21 mm. Similar to male, except abdominal tergite 2 with yellow scales anteriorly and laterally. Type material. Holotype ♂ CHINA: Shanxi, Changzhi, Taihang Canyon, 15. VII. 2020, Gang Yao (sweep netting). Paratypes ♂ (14), ♀ (14), CHINA: Beijing, Yanqing, Xiahujiao Village, 15. VII. 2020, Xu Zhang (yellow pans). Live photos were taken by Shan Gui in Xinglong county, Hebei Province and in in Miyun and Huairou District, Beijing (Fig. 5). Distribution. China (Beijing, Hebei, Shanxi). Etymology. The species is named after the photographer Shan Gui. Remarks. Live photos were taken by Shan Gui in Xinglong County, Hebei Province and in Miyun and Huairou, Beijing (Fig. 5). The new species is similar to L. belzebul (Fabricius), but can be separated by the wing mostly infuscated with darker areas close to veins, tergite 1 with basal half black and apical half yellow and with dense yellow hairs laterally and sparse yellow hairs medially. In Lomatia belzebul, the wing has only the anterior 1/4 infuscated, and the remainder parts hyaline; and tergite 1 is entirely black with the yellowish hairs laterally., Published as part of Yao, Gang, Luo, Jun, Li, Xuankun & Yang, Ding, 2022, First records of the subfamilies Ecliminae and Lomatiinae (Diptera, Bombyliidae) from China with description of two new species, pp. 396-408 in Zootaxa 5094 (3) on pages 399-402, DOI: 10.11646/zootaxa.5094.3.2, http://zenodo.org/record/5974168

Genus Lomatia Meigen, 1822 Stygia Meigen, 1820: 137. Type species: Anthrax belzebul Fabricius, 1794, by subsequent designation (Westwood, 1840: 131) [Type designation for Lomatia Meigen, 1822, with Stygia in synonymy]. [Preoccupied by Latreille, 1804.] Lomatia Meigen, 1822: [Vorrede] (unpaginated) [1830: 324] (new replacement name for Stygia Meigen, 1820). Type species: Anthrax belzebul Fabricius, 1794, by subsequent designation (Westwood, 1840: 131). Stygide Latreille, 1825: 491 (new replacement name for Stygia Meigen, 1820). [Unavailable; vernacular name without status in nomenclature.] Stygidium Berthold, 1827: 500 (new replacement name for Stygia Meigen, 1820). Type species: Anthrax belzebul Fabricius, 1794, automatic. Stygides Latreille, 1829: 465 (new replacement name for Stygia Meigen, 1820). Type species: Anthrax belzebul Fabricius, 1794, automatic. Nettadion Gistel, 1848: ix (unjustified new replacement name for Lomatia Meigen, 1822). Type species: Anthrax belzebul Fabricius, 1794, automatic. Ancentralis Bezzi, 1925: 199. Type species: Anthrax pictipennis Wiedemann, 1828, by monotypy. [Unavailable; name proposed in specific synonymy with Anthrax pictipennis Wiedemann and not made available before 1961. See Evenhuis (1991: 18) for details.], Published as part of Yao, Gang, Luo, Jun, Li, Xuankun & Yang, Ding, 2022, First records of the subfamilies Ecliminae and Lomatiinae (Diptera, Bombyliidae) from China with description of two new species, pp. 396-408 in Zootaxa 5094 (3) on pages 398-399, DOI: 10.11646/zootaxa.5094.3.2, http://zenodo.org/record/5974168, {"references":["Meigen, J. W. (1822) Systematische Beschreibung der bekannten europaischen zweiflugeligen Insekten. Dritter Theil. Schultz- Wundermann, Hamm, x + 416 pp.","Meigen, J. W. (1820) Systematische Beschreibung der bekannten europaischen zweiflugeligen Insekten. Zweiter Theil. F. W. Forstmann, Aachen, x + 363 pp.","Fabricius, J. C. (1794) Entomologia systematica emendata et aucta. Secundum classes, ordines, genera, species adjectis synonimis, locis, observationibus, descriptionibus. Tome IV. C. G. Proft, Hafniae [Copenhagen], [6] + 472 + [5] pp.","Westwood, J. O. (1840) Order XIII. Diptera Aristotle. (Antliata Fabricius. Halteriptera Clairv.). In: In his: An introduction to the modern classification of insects; founded on the natural habits and corresponding organization of the different families. Synopsis of the genera of British insects. Longman, Orme, Brown, Green and Longmans, London, pp. 125 - 154. https: // doi. org / 10.5962 / bhl. title. 12455","Latreille, P. A. (1804) Tableau methodique des insectes. In: Nouveau dictionnaire d'histoire naturelle, applique aux arts, principalement a l'agriculture et a l'economie rurale et domestique. Tome XXIV. Section 3. tableaux methodiques d'histoire naturelle. Deterville, Paris, pp. 129 - 200.","Latreille, P. A. (1825) Familles naturelles du regne animal, exposees succinctement et dans un ordre analytique, avec l'indication de leurs genres. J. - B. Bailliere, Paris, 570 pp. https: // doi. org / 10.5962 / bhl. title. 16094","Berthold, A. A. (1827) Naturliche Familien des Thierreichs. Aus dem Franzosischen. Mit Anmerkungen und Zusatzen. Landes- Industrie, Weimar, x + 606 pp.","Latreille, P. A. (1829) Suite et fin des insectes. In: Cuvier, [G. l. C. F. D.], Le regne animal distribue d'apres son organisation, pour servir de base a l'histoire naturelle des animaux et d'introduction a l'anatomie comparee. Avec figures dessinees d'apres nature. Nouvelle edition, revue et augmentee. Tome V. Deterville et Crochard, Paris, xxiv + 556 pp.","Gistel, J. N. F. X. (1848) Naturgeschichte des Thierreichs, fur hohere Schulen. R. Hoffman, Stuttgart, xvi + 216 + [4] pp.","Bezzi, M. (1925) Quelques notes sur les bombyliides (Dipt.) d'Egypte, avec description d'especes nouvelles. Bulletin de la Societe Royal d'Entomologique d'Egypte, 8, 159 - 242.","Wiedemann, C. R. W. (1828) Aussereuropaische zweiflugelige Insekten. Als Fortsetzung des Meigenschen Werkes. Erster Theil. Schulz, Hamm, xxxii + 608 pp.","Evenhuis, N. L. (1991) World catalog of genus-group names of bee flies (Diptera: Bombyliidae). Bishop Museum Bulletins in Entomology, 5, i - vii + 1 - 105."]}

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.

Endemism and rarity have long intrigued scientists. We focused on a rare endemic and critically-endangered species in a global biodiversity hotspot, Grevillea thelemanniana (Proteaceae). We carried out plant and soil analyses of four Proteaceae, including G. thelemanniana, and combined these with glasshouse studies. The analyses related to hydrology and plant water relations as well as soil nutrient concentrations and plant nutrition, with an emphasis on sodium (Na) and calcium (Ca). The local hydrology and matching plant traits related to water relations partially accounted for the distribution of the four Proteaceae. What determined the rarity of G. thelemanniana, however, was its accumulation of Ca. Despite much higher total Ca concentrations in the leaves of the rare G. thelemanniana than in the common Proteaceae, very few Ca crystals were detected in epidermal or mesophyll cells. Instead of crystals, G. thelemanniana epidermal cell vacuoles contained exceptionally high concentrations of noncrystalline Ca. Calcium ameliorated the negative effects of Na on the very salt-sensitive G. thelemanniana. Most importantly, G. thelemanniana required high concentrations of Ca to balance a massively accumulated feeding-deterrent carboxylate, trans-aconitate. This is the first example of a calcicole species accumulating and using Ca to balance accumulation of an antimetabolite.

OCBIL theory provides a basis for understanding of the evolution and ecology of biota on old, climatically buffered, infertile landscapes (OCBILs) worldwide. Here, we test a genetic hypothesis presented in OCBIL theory that predicts highly differentiated intraspecific population systems on OCBILs vs. more limited differentiation on young, often disturbed, fertile landscapes (YODFELs). We examined patterns of genomic and morphological divergence in Banksia seminuda across OCBILs and YODFELs in south-western Australia. We also used these data to determine whether these OCBIL and YODFEL populations represent distinct subspecific lineages, a point of previous contention among taxonomists. As hypothesized, genomic analyses based on 3466 SNP loci revealed strong structuring within B. seminuda, with high differentiation across narrow geographic scales among OCBIL populations vs. lower differentiation across much larger geographic scales among YODFEL populations. In addition, genomic and morphological divergence was found between OCBIL and YODFEL populations, providing comprehensive quantitative evidence for two subspecies. These findings have taxonomic implications for the species and provide support for OCBIL theory and its insights into the evolution, ecology and conservation of biota on ancient landscapes.

Gevuina avellana and Lomatia dentata are Proteaceae species from evergreen temperate forests, but only G. avellana can colonize nutrient deprived volcanic depositions. We hypothesized that under nutrient deprivation, G. avellana would present higher survival, physiological performance, and adjustment regarding cluster root (CR) formation and carboxylate exudation rate than L. dentata. We evaluated relative growth rate, maximal photosynthetic rate, photochemical performance, nitrogen (N) and phosphorus (P) leaf concentrations, specific leaf area, photosynthetic P and N use efficiency (PPUE and PNUE), CR formation and carboxylate exudation rate. Plants were grown in a greenhouse, using recent volcanic substrate and watered with different nutrient Hoagland (H) solutions: modified full Hoagland, without P, without N, or tap water. Both species showed high survival. G. avellana exhibited higher growth rates (RGR), and higher CR number and biomass allocation under nutrient deprivation, but lower carboxylate exudation rates than L. dentata. Malate, oxalate and succinate were detected in root exudates of G. avellana but only oxalate in L. dentata. However, PPUE and PNUE were higher in L. dentata than in G. avellana . Our hypothesis was not entirely accepted, CR formation was more “constitutive” in G. avellana, and composition of carboxylates was more diverse, with lower exudation rates than L. dentata. Moreover, L. dentata showed higher PNUE and PPUE, partly explained by thinner leaves. Different responses are related with edaphic conditions, where both species inhabit: more diverse to G. avellana and restricted to developed soils to L. dentata.

Plants that produce specialised cluster roots, which mobilise large quantities of poorly available nutrients such as phosphorus (P), can provide a benefit to neighbouring plants that produce roots in the cluster rhizosphere, as demonstrated previously in pot studies. To be effective, such roots must be present within the short time of peak cluster activity. We tested if this requirement is met, and quantified potential P benefits, in a hyperdiverse Mediterranean woodland of southwest Australia where cluster-rooted species are prominent. Using minirhizotrons, we monitored root dynamics during the wet season in the natural habitat. We found non-cluster roots intermingling with all 57 of the observed cluster roots of the studied tree species, Banksia attenuata. Almost all (95%) of these cases were observed in a high-moisture treatment simulating the 45-year average, but not present when we intercepted some of the rainfall. We estimate that cluster-root activity can increase P availability to intermingling roots to a theoretical maximum of 80% of total P in the studied soil. Due to their high P-remobilisation efficiency (89%), which results from P rapidly being relocated from cluster roots within the plant, senesced Banksia cluster roots are a negligible P source for other roots. We conclude that, rather than serving as a P source, it is the cluster-root activity, particularly the exudation of carboxylates, that may improve the coexistence of interacting species that are capable of root intermingling, thus potentially promoting species diversity in nutrient-poor habitats, and that this mechanism will be less effective in a drying climate.

Firstly, we show that dead leaf retention occurs in three Cape Protea species and that it is not correlated with a prolonged live leaf retention. Protea amplexicaulis retains dead leaves for up to six years and was used as a focal species. Two hypotheses for the adaptive significance of dead leaf retention in Proteaceae have been previously suggested: that dead leaves increase flammability thus providing open space for seedling establishment by burning neighbouring plants (Flammability hypothesis); and that the retention of dead leaves results in an increase in post-fire nutrients thus providing fertilisation for seedlings (Selfish fertilisation hypothesis). Dead leaves were found to contain significant amounts of calcium but negligible amounts of any other limiting nutrients and below canopy seedlings were neither more numerous nor larger than those in the open. We thus reject the selfish-fertilization hypothesis. We reject the flammability hypothesis as both P. amplexicaulis and its most common near neighbours are fire sensitive reseeders and in any case seeds are likely to disperse outside of the area affected by increased parental flammability.

Australian macadamia production is threatened by a disorder known as abnormal vertical growth (AVG), for which the etiology is unknown. AVG is characterized by vigorous upright growth and reduced lateral branching, flowering, and nut set that results in over 70% yield loss annually. Six commercial macadamia orchards were surveyed in 2012 and again in 2018 to examine spatiotemporal dynamics of the epidemic. Data were subjected to point-pattern and geostatistical analyses. AVG incidence in all orchards showed a better fit to the beta-binomial distribution than the binomial distribution. AVG incidence in the different orchards varied between 5 and 47% in 2012, and 13 and 55% in 2018 and the rate of spread was slow, averaging at about 2% increase in disease incidence per annum. Spatial patterns of AVG were highly aggregated on both survey years and spread was mainly between neighboring trees in a row or trees that were opposite to each other in different rows. Semivariograms showed large range values (approximately 15 to 120), indicating aggregation of AVG-affected trees beyond quadrat levels. Furthermore, clusters of disease were mainly at the edge of the orchard on the first survey date and the disease progressed toward the center of the orchard over time. It is concluded that AVG is caused by an infectious agent, and based on patterns of spread, we hypothesize that spread is facilitated by root grafting or root-to-root contact. Furthermore, a vascular-limited pathogen could be involved that modulates plant hormone production.

In Australia, Phytophthora cinnamomi is the only species reported as the causal agent of stem canker and root rot in macadamia. In other countries, five Phytophthora species have been reported to cause diseases in macadamia, which led us to question if more than one Phytophthora species is responsible for poor tree health in macadamia orchards in Australia. To investigate this, samples were collected from the rhizosphere, stem, and root tissues of trees with and without symptoms, nurseries, and water sources from 70 commercial macadamia orchards in Australia. Phytophthora isolates were identified based on morphological characteristics and DNA sequencing. P. cinnamomi was the most predominant and widely distributed species, and was obtained from the different types of samples including symptomless root tissues. In addition to P. cinnamomi, only P. multivora was isolated from diseased tissue (stem canker) samples. Six other Phytophthora species were obtained from the rhizosphere samples: P. pseudocryptogea, P. citrophthora, P. nicotianae, P. gondwanense, P. sojae, and a new Phytophthora taxon. Only P. cinnamomi was obtained from macadamia nursery samples, while five Phytophthora species were obtained from water sources. Of the heterothallic Phytophthora species, mating type A2 isolates were dominant in P. cinnamomi isolates, whereas only mating type A1 isolates were obtained for P. nicotianae, P. pseudocryptogea, and P. citrophthora. Pathogenicity assays revealed that P. cinnamomi and P. multivora caused significantly larger stem and leaf lesions than P. citrophthora, P. nicotianae, and P. pseudocryptogea. Phytophthora sp. and P. sojae were nonpathogenic towards leaves and stems.

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.

Phomopsis husk rot (PHR) in macadamia is a disease of economic importance in major commercial production areas in Australia and South Africa. Effective control of PHR is hindered by limited knowledge about its aetiology and epidemiology. The diversity and pathogenicity of more than 50 isolates of Diaporthe associated with PHR in macadamia orchards in Australia and South Africa was assessed. Multilocus phylogenetic analyses of DNA sequences of the ITS, tef1α, and tub2 gene loci revealed four novel clades that are described as Diaporthe australiana sp. nov., D. drenthii sp. nov., D. macadamiae sp. nov., and D. searlei sp. nov. Pathogenicity tests with representative isolates found that all four species caused PHR of varying severity between and within species, as well as between the two macadamia cultivars HAES 344 and HAES 816. The Australian species, D. australiana, was the most aggressive species compared with the three South African species. This study improves our understanding of the aetiology of PHR in macadamia and paves the way for more effective disease management.

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.

The composition of diet reflects the food availability and food preference by wildlife in their respective habitat. Flying fox (Pteropus giganteus) is the largest bat species that inhabit the urban area of Kathmandu Valley. The diet composition of Flying fox and their conservation threat was studied from January to April 2018. Bats roosting at Kesharmahal, Kathmandu and Sallaghari, Bhaktapur were selected for the study. The diet consumed was explored by micro-histological analysis from fresh fecal samples (guano) and bolus collected from the roost site. The samples were collected by spreading plastic sheets of 2m × 2m for a whole day. The droppings from bats were collected on 50 mL vials with 70% alcohol. Altogether 140 samples were collected. The collected droppings were used to micro histological slides where the seeds were isolated and identified using a hand lens. The pollens presence in slides were observed under the compound microscope and tallied with the reference slides for identification. Altogether 17 and 10 different plant families were identified from dropping of bats from Kesharmahal and Sallaghari, respectively. Among them, Moraceae and Myrtaceae were common diets in bats of both locations. Our result shows P. giganteus consumes food from the Myrtaceae, Brassicaceae, Malvaceae, Apiaceae, Pinaceae, Fagaceae, Proteaceae and Anacardiaceae families in Kathmandu Valley. P. giganteus mostly depend on foods present nearby the roost and also flies far away in search of food, which is comparatively minimal.

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.

Variation in xylem conduit diameter traditionally has been explained by climate, whereas other evidence suggests that tree height is the main driver of conduit diameter. The effect of climate versus stem length on vessel diameter was tested in two tree species (Embothrium coccineum, Nothofagus antarctica) that both span an exceptionally wide precipitation gradient (2300-500 mm). To see whether, when taking stem length into account, plants in wetter areas had wider vessels, not only the scaling of vessel diameter at the stem base across individuals of different heights, but also the tip-to-base scaling along individuals of similar heights across sites were examined. Within each species, plants of similar heights had similar mean vessel diameters and similar tip-to-base widening of vessel diameter, regardless of climate, with the slopes and intercepts of the vessel diameter-stem length relationship remaining invariant within species across climates. This study focusing on within-species variation--thus, avoiding noise associated with the great morphological variation across species--showed unequivocally that plant size, not climate, is the main driver of variation in vessel diameter. Therefore, to the extent that climate selects for differing vessel diameters, it will inevitably also affect plant height.

Abnormal vertical growth (AVG) syndrome is a serious threat to the Australian macadamia industry as it decreases the yield of nuts by as much as 70% per annum. A lack of information on the cause of AVG has hindered the development of an effective disease management strategy. Discovery of genetic markers associated with disease resistance can be used as tool for rapid selection of elite cultivars, hence helps in efficient disease management. Differences in field susceptibility of macadamia cultivars provide an opportunity for discovery of genetic markers that are associated with host resistance. REML mixed model analysis was performed to estimate the AVG rating of 51 cultivars from multiple origins using phenotypic data from 359 trees planted in four sites. Most of the Hawaiian cultivars were found as susceptible, while selections from the Australian macadamia industry breeding program were predominantly resistant. All the cultivars were genotyped for 13,221 DArTseq-based single nucleotide polymorphism (SNP) markers. A bulked sample analysis was performed using 20 genotypes each at the extremes of AVG phenotypic ratings. Ten SNP markers were predicted to be associated with AVG resistance and two arbitrarily selected SNP markers were validated using PCR and Sanger sequencing. Our findings suggest that AVG resistance in the commercial cultivars may be derived from the genomic introgression of Macadamia tetraphylla through interspecific hybridization. The results may support marker-assisted selection for macadamia germplasm with AVG resistance.

Telopea speciosissima, the New South Wales waratah, is an Australian endemic woody shrub in the family Proteaceae. Waratahs have great potential as a model clade to better understand processes of speciation, introgression and adaptation, and are significant from a horticultural perspective. Here, we report the first chromosome-level genome for T. speciosissima. Combining Oxford Nanopore long-reads, 10x Genomics Chromium linked-reads and Hi-C data, the assembly spans 823 Mb (scaffold N50 of 69.0 Mb) with 97.8% of Embryophyta BUSCOs "Complete". We present a new method in Diploidocus (https://github.com/slimsuite/diploidocus) for classifying, curating and QC-filtering scaffolds, which combines read depths, k-mer frequencies and BUSCO predictions. We also present a new tool, DepthSizer (https://github.com/slimsuite/depthsizer), for genome size estimation from the read depth of single-copy orthologues and estimate the genome size to be approximately 900 Mb. The largest 11 scaffolds contained 94.1% of the assembly, conforming to the expected number of chromosomes (2n = 22). Genome annotation predicted 40,158 protein-coding genes, 351 rRNAs and 728 tRNAs. We investigated CYCLOIDEA (CYC) genes, which have a role in determination of floral symmetry, and confirm the presence of two copies in the genome. Read depth analysis of 180 "Duplicated" BUSCO genes using a new tool, DepthKopy (https://github.com/slimsuite/depthkopy), suggests almost all are real duplications, increasing confidence in the annotation and highlighting a possible need to revise the BUSCO set for this lineage. The chromosome-level T. speciosissima reference genome (Tspe_v1) provides an important new genomic resource of Proteaceae to support the conservation of flora in Australia and further afield.

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.

Background The presence of geminivirus sequences in a preliminary analysis of sRNA sequences from the leaves of macadamia trees with abnormal vertical growth (AVG) syndrome was investigated. Results A locus of endogenous geminiviral elements (EGE) in the macadamia genome was analysed, and the sequences revealed a high level of deletions and/or partial integrations, thus rendering the EGE transcriptionally inactive. The replication defective EGE in the macadamia genome indicates its inability to be the source of new viral infections and thus cause AVG or any other disease in macadamia. The EGE sequences were detected in two edible Macadamia species that constitute commercial cultivars and the wild germplasm of edible and inedible species of Macadamia. This strongly suggests that the integration preceded speciation of the genus Macadamia. A draft genome of a locus of EGE in Macadamia was developed. The findings of this study provide evidence to suggest the endogenization of the geminiviral sequences in the macadamia genome and the ancestral relationship of EGE with Macadamia in the Proteaceae family. Random mutations accumulating in the EGE inform that the sequence is evolving. Conclusions The EGE in Macadamia is inactive and thus not a direct cause of any diseases or syndromes including AVG in macadamia. The insertion of the EGE in the macadamia genome preceded speciation of the genus Macadamia.

Grevillea speckiana Olde is described from a single collection gathered in 1953. Although the specimens bears flowers in early bud, fruits and foliage are sufficient to assign and describe the species. Unlike several other species in the Triloba Group awaiting description from single specimens that represent extinct species, there is some hope for its continued existence because of the botanically unexplored locality in which it was collected.