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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.

Between 1778 and 1903, three successive generations of the Wendland family were Court Gardeners at the Royal Gardens of Herrenhausen, Hanover, Germany. In addition to their horticultural responsibilities, they published several important taxonomic accounts, some involving Australian plants. Johann Christoph Wendland (1755–1828) (J.C.Wendl.) established the endemic Australian genera Angianthus J.C.Wendl. (Asteraceae), Hakea Schrad. & J.C.Wendl. (Proteaceae) and Waitzia J.C.Wendl. (Asteraceae), and provided novel work on Melaleuca L. (Myrtaceae) and Acacia Mill. (as Mimosa L; Fabaceae); Heinrich Ludolph Wendland (1792–1869) (H. L.Wendl.) provided novel and revisionary work on Acacia and Leptospermum J.R.Forst. & G.Forst. (Myrtaceae); and Hermann Wendland (1825–1903) (H. Wendl.) specialised in the palms (Arecaceae) and wrote Palmae Australasicae with Oscar Drude, the foundational work on Australian palms. A search of all the databases and other references accessible to us has resulted in the identification of ~148 names of Australian plants in which the author citation includes any of the three Wendlands. Of these, ~30 are the currently accepted names. Lectotypes are here proposed for the names Acacia amoena H.L.Wendl., A. crassiuscula H.L.Wendl., A. dolabriformis H.L.Wendl., A. emarginata H.L.Wendl., A. homomalla H.L.Wendl., Aster tomentosus J.C.Wendl., Leptospermum buxifolium H.L.Wendl., L. emarginatum H.L.Wendl. ex Link, L. glomeratum H.L.Wendl., Melaleuca linearis Schrad. & J.C.Wendl., M. thea Schrad. & J.C.Wendl., Passiflora glabra J.C.Wendl., Protea nectarina J.C.Wendl., P. pulchella Schrad. & J.C.Wendl., Pultenaea daphnoides J.C.Wendl., P. linophylla Schrad. & J.C.Wendl., P. retorta J.C.Wendl. and Tristania subverticillata H.L.Wendl. Figures are provided of all the proposed lectotypes housed in GOET.

Little is known about accidental epiphytes in Australian temperate forests. In western Tasmania, we determined whether: (1) the occurrence and abundance of accidental epiphytes increases with moisture availability and the size of host; (2) the species of host affects the occurrence of individual taxa of accidental epiphytes; (3) moist microhabitats favour accidental epiphytes. We recorded the accidental woody epiphytes on 21 trees in each of 20 locations and measured attributes of the host and the location and attachment height of the individual epiphytes. Epiphyte occurrence, but not abundance, was associated with the basal area of host tree, January rainfall and the taxon of the host. Eucalypts, gymnosperms and tree ferns were the outstanding hosts. The rainforest tree Nothofagus cunninghamii occurred as an epiphyte on eucalypts more than expected, while Proteaceae species occurred less than expected. In contrast, there was a strong positive association between the gymnosperm Athrotaxis selaginoides as a host and Proteaceae as epiphytes, possible reflecting their joint status as palaeoendemics. Accidental epiphytes were concentrated on the west and south-west of trees and near their bases, further indicating a strong effect of moisture availability on their occurrence. Our results reinforce the importance of conserving old growth forest to maintain ecosystem complexity.

Banksia microphylla leaf fossils and Banksieaeidites zanthus pollen are newly described from late Eocene lignite of the Zanthus-11 borehole, drilled east of Norseman in Western Australia. The leaf fossils are the first known in Banksia to show extreme narrowness (

Interspecific variation in plant hydraulic traits plays a major role in shaping species distributions across climates, yet variation within species is poorly understood. Here we report on intraspecific variation of hydraulic traits in Banksia serrata (L.f.) sampled from three sites characterised by contrasting climates (warm-wet, warm-dry and cool-wet). Hydraulic characteristics including vulnerability to embolism, hydraulic conductance, pressure-volume traits and key morphological traits were measured. Vulnerability to embolism in leaf and stem, defined by the water potential inducing 50 and 88% loss of hydraulic conductivity (P50 and P88 respectively), did not differ across sites. However, plants from the warm-dry environment exhibited higher stem conductivity (Ks) than the cool-wet environment. Leaf turgor loss point (TLP) did not vary among sites, but warm-dry site plants showed lower leaf capacitance (C*FT) and higher modulus of elasticity (ε) than the other two sites. Plants from the cool-wet site had lower specific leaf area (SLA) and plants from the warm-dry site had lower sapwood density (WD). Overall, key hydraulic traits were generally conserved across populations despite differences in mean site water availability, and the safety-efficiency trade-off was absent in this species. These results suggest that B. serrata has limited ability to adjust hydraulic architecture in response to environmental change and thus may be susceptible to climate change-type drought stress.

Development of embryo envelopes in Leucospermum cordifolium (Salisb. ex Knight) Fourcade is presented in a detailed anatomical study, and their structure interpreted ecologically. To support interpretation results for at least six other species of Leucospermum are reviewed, confirming that L. cordifolium is representative of this shrubby group occurring in fynbos, a fire-prone Mediterranean-type vegetation subject to summer drought. The fate of the water-permeable seed coverings subsequent to dispersal is followed in seeds stored experimentally underground. The testa at maturity effectively excludes oxygen in intact soil-stored seeds, thus creating a less common type of physical dormancy which we term ‘anoxia PY’ (oxygen-impermeable physical dormancy). We postulate ‘fire-mediated desiccation-scarification’ testa breakage on a large scale in freshly dispersed (by ants) soil-stored young-seeds, dynamically regulated by drying of different testa layers through fire heat shock (but also by post-fire ambient climate heat), thus alleviating anoxia PY in, and causing undelayed germination of, a major part of the young-seed bank within the ensuing winter germination season. Concurrently a patchy disturbance pattern within a lesser portion of the young-seed cohort causes uneven underground desiccation-scarification by fire, resulting in variable degrees of oxygenation and thus temporally extended (erratic) germination of young-seeds. Both of these strategies are primary long term fitness traits in Leucospermum. By contrast the persistent older-seed cohort, stored underground during the inter-fire period, may become weathered by soil and climate factors (‘soil-mediated abrasion’), which alleviates anoxia PY in old seeds. Thermodormancy of these embryos (physiological dormancy, PD) is enforced in unburnt vegetation by two narrow habitat-dependent daily temperature requirements (~10°C × 20°C), and these have specific ecological functions. The complex Leucospermum system includes balanced adaptive responses to multiple selective pressures. We propose a coherent mechanistic profile for this fynbos genus, synthesising data partly from the literature of other fire-prone ecosystems.

The Cape Leucadendron genus is dioecious, with extreme vegetative dimorphism displayed in some species – females having much larger leaves and fewer branches than males – whereas other species are monomorphic. Leucadendron is ecologically diverse, with some species with canopy stored seeds (serotiny) and others with soil stored seeds. These features mean that the Cape Leucadendron is an ideal genus to study the costs of reproduction for the different sexes in plants, and to determine whether vegetative dimorphism could be due to unequal costs. Here we use the unique aspects of the fire-prone Cape environment in which leucadendrons occur to show that the costs of sex must be equal between the sexes. Leucadendron populations are single aged because they only recruit after fires that kill all adults. Therefore, because the sexes have the same lifespans, they must have the same lifetime extent of vegetative versus reproductive allocation. Also, ecologically similar hermaphrodite Proteaceae co-exist with dioecious taxa. To co-occur, dioecious and hermaphrodite taxa must have the same mean post-fire fitness. This implies that dioecious females must have double the reproductive output that a co-occurring hermaphrodite has. This is only possible if the costs of reproduction are the same for the sexes and that the sexes use the same resources for reproduction. Finally, because males and female co-occur, they must be competitively equivalent to maintain natal sex ratios. These three factors suggest male and female allocate equivalently and therefore that vegetative sexual dimorphism is unlikely to be due to differences in allocation.

Pollen limitation occurs frequently in plant populations and, as result, many ovules are wasted. One possible adaptive explanation posits that ovule overproduction represents a 'bet-hedging' strategy against pollination inefficiency. This hypothesis is supported by comparative evidence showing that unpredictability in pollen receipt is positively associated with an increasing number of ovules per flower across species. Yet, this proposition has not been tested at the intraspecific level, where natural selection operates. Here, we evaluated the relationship between pollination unpredictability, considering both pollination quantity and quality, and number of ovules per flower, across 16 populations of the south-Andean generalist treelet Embothrium coccineum J.R.Forster and G.Forst from north-western Patagonia, which occurs along a west-east gradient of decreasing rainfall. Despite sizable variation in mean number of ovules per flower, we found no increase in ovule production with increasing pollination unpredictability across populations. Instead, we found that mean number of ovules per flower decreased with decreasing rainfall. Therefore, in this species, there was no support for the proposal that ovule overproduction represents a bet-hedging strategy against unpredictable pollen receipt. Rather, the number of ovules per flower seems to be conditioned primarily by resource availability. Fil: Chalcoff, Vanina Ruth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Aizen, Marcelo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Fossils from the Eocene of South Australia and Western Australia and the Oligo–Miocene of Victoria represent the first known Australian leaf fossils of subfamily Persoonioideae, tribe Persoonieae. Persoonieaephyllum blackburnii sp. nov. is described from Middle Eocene Nelly Creek sediments near Lake Eyre, South Australia. Persoonieae are an important clade for understanding vegetation transitions in Australasia. The Nelly Creek leaf fossils are small (~6mm wide) and belong to an assemblage that has some characteristics of open vegetation, which is also inferred for the Oligo–Miocene of the Latrobe Valley, Victoria. In contrast, the Western Australian Late Eocene Persoonieae occur with diverse Lauraceae and other elements now typical of closed rainforests, and may, therefore, have been derived from communities that are unlike those in which most Persoonieae now occur. All fossil Persoonieae leaves so far known are hypostomatic (or virtually so), a state of stomatal distribution now only found in species of reasonably mesic habitats in New Zealand, New Caledonia and eastern Australian eucalypt forests. The ancestral state of stomatal distribution in Persoonieae leaves is unclear, but evidence suggests ancient associations of amphistomaty with open habitats, evolutionary loss of adaxial stomata in more closed vegetation, and the evolution of pronounced xerophylly within south-western Australian heathlands.

The genus Banksieaephyllum, originally erected for cuticle-bearing fossil leaves of subtribe Banksiinae (Proteaceae subfamily Grevilleoideae, tribe Banksieae), is reassessed. Of the 18 described species, nine are accepted within Banksia, including Banksieaephyllum obovatum Cookson & Duigan, which is synonymised with B. laeve Cookson & Duigan on the basis of new cuticular preparations. Two other species are transferred to Banksieaefolia gen. nov., a genus erected for Banksieae of uncertain affinities, and which presently includes only fossils that probably belong to subtribe Musgraveinae. The seven other Banksieaephyllum species lack definitive characters of Proteaceae (i.e. brachyparacytic stomata and annular trichome bases) and do not have Banksieae-type cylindrical trichome bases. These species are, therefore, not accepted as Proteaceae and are transferred to Pseudobanksia gen. nov., together with another fossil Banksia-like leaf species, Phyllites yallournensis Cookson & Duigan. Lectotypes are chosen for Banksia fastigata H.Deane, Banksieaephyllum acuminatum Cookson & Duigan, Banksieaephyllum angustum Cookson & Duigan and Banksieaephyllum laeve Cookson & Duigan. Implications arising from the re-assessment of Banksieaephyllum include clarification of biome conservatism in Banksieae; Banksia has long had an association with relatively open, sclerophyllous vegetation, and Musgraveinae with rainforest. Pseudobanksia and Banksia share convergent traits, but in contrast to Banksia, Pseudobanksia failed to survive the drying climates and increased fire-frequencies of the Neogene.

Flower visitation by small mammals is difficult to observe directly on account of their sensitivity to human presence and the nocturnal activity of some species. Their role in pollination has, thus, been inferred mostly from analysis of fur and faecal pollen loads of field-trapped animals. The development of motion-activated remote cameras allows for unprecedented insights into natural behaviours of small mammals on flowers. We used remote cameras to assess the identity of flower visitors, and the frequency and timing of their visitation to flower heads of four poorly studied Protea species (P. cordata, P. decurrens P. scabra and P. subulifolia) that were predicted to be rodent-pollinated on the basis of floral traits. Camera footage revealed that small mammals (typically three to six rodent species per Protea species) were frequent visitors to flower heads over one flowering season, making up 100% of visits to P. cordata and P. subulifolia, 98% of visits to P. decurrens, and 90% of visits to P. scabra. Rodents that are known pollinators of other ground Protea species, such as Acomys subspinosus, Micaelamys namaquensis and Rhabdomys pumulio, were observed to make contact with reproductive parts of the flowers, but further work would be required to demonstrate unequivocally that they are the main pollen vectors of these species. Mus minutoides was recorded for the first time to frequently visit inflorescences of P. subulifolia. Other visitors included genets that visited P. scabra inflorescences to lick nectar off florets, and birds that were relatively infrequent visitors to all species. Together with recent literature, the present study has shown that the utilisation of remote cameras in pollination studies provides an efficient, discreet method for observing vertebrate flower-visiting behaviour.

Hakea (Proteaceae) currently comprises over 150 species, with two-thirds confined to south-western Australia (SWA) and the remainder spread throughout Australia, especially along the eastern coast. We constructed a time-based molecular phylogeny for the genus and used area-assignment techniques to trace its biogeographic history. According to our area-cladogram analysis, there is a 95% probability that Hakea arose 18 million years ago (Ma) in the sandplains of SWA. From 12 Ma, the genus speciated and migrated into forest and onto granite outcrops within SWA, into the drier centre and then continued to the maritime forests of eastern Australia (EA) 3000 km away, and north-east to savanna grasslands. The Nullarbor Plain was an obstacle but it did not prevent eastward migration. Twelve west➔east, apparently allopatric, speciation events are identified that coincided with glacial maxima, but more likely represent sympatric speciation in SWA or central Australia, followed by further migration and speciation➔extinction➔speciation events across central to EA. During the period from 8 to 1 Ma, net speciation has been linear and strong in the sclerophyll shrublands of SWA and, to a lesser extent, the sclerophyll forests of EA. Four lines of evidence (historical distribution of sclerophyllous Proteaceae, historical subjection to aridity, species diversification patterns, relative allocation of drought-adapted traits) support our area-cladogram results that Hakea originated in SWA and gradually spread to all parts of Australia as suitable nutrient-impoverished, and open drought- and fire-prone habitats became available.

Cookson (1950) erected the fossil pollen genus Banksieaeidites to accommodate palynomorphs with characters resembling those of the extant Proteaceae genus Banksia. One of the most commonly reported species, Banksieaeidites arcuatus Stover & A.D.Partr., is now known to more closely resemble pollen of the Proteaceae subtribe Musgraveinae, than that of subtribe Banksiinae. The late Eocene Mulga Rock deposits in the southern Officer Basin of Western Australia have yielded palynofloras that contain up to 7% of two new species that can confidently be aligned with pollen of modern Banksia. Banksieaeidites davidsonii sp. nov. and B. rugulus sp. nov. are formally described, and pollen from eight extant Banksia are described and compared with the two fossil species. The variation in extant Banksia L.f. pollen morphology, and that between the two Banksia subgenera (B. subgenus Banksia and B. subgenus Spathulatae A.R.Mast & K.R.Thiele) are discussed, and the changes in the morphology of Banksia pollen grains as they mature are reported.

In the South-west Australian Floristic Region, timing of rainfall is critical for successful seedling establishment, as is surviving the first year’s summer drought for population persistence. Predictions of a warmer, drier future, therefore, threaten the persistence of obligate seeding species. Here, we investigate the drought tolerance of two co-occurring Banksia (Proteaceae) species by withholding water in pots to different extents of soil drying. Seed was collected from high- and low-rainfall populations, to test for niche differentiation in water-use strategies at the species level, as well as population differentiation. On the basis of a more negative leaf water potential at minimal levels of stomatal conductance and quantum yield, B. coccinea was considered to be more drought tolerant than B. baxteri. This was supported at the anatomical level according to xylem-vessel attributes, with a higher estimated collapse pressure suggesting that B. coccinea is less vulnerable to xylem cavitation. Population contrasts were observed mainly for B. baxteri, with a lower leaf-expansion increment rate in the low-rainfall population providing for drought avoidance, which was reflected in a higher rate of survival than with the high-rainfall population in which 87.5% of plants showed complete leaf senescence. The implications of species differences in water-use strategies are that community dynamics may start to shift as the climate changes. Importantly, this shift may be population dependent. A systematic understanding of adaptive capacity will help inform the choice of population for use in revegetation programs, which may lead to increased resilience and persistence in the face of environmental change. The results of the present study suggest that should declines in B. baxteri populations be noted, revegetating with seed collected from the low-rainfall population may help improve the chances of this species surviving into the future.

The purpose of this research was to examine the effect of the seed coat on seed dormancy in Grevillea (Proteaceae) species, and to further investigate the existence of germination inhibitors in Grevillea seed coat extracts. Seed dormancy of 18 Grevillea accessions involving 17 species was investigated: results indicated that removal of seed coat increased seed germination from 0–6% (intact seeds) to 83–100% for the Grevillea accessions and removal of half seed coat resulted in no increase in seed germination. Grevillea seed coat extracts reduced germination of barley, canola, lupin and ryegrass seeds by 48, 57, 10 and 38% respectively. The extracts also reduced seedling growth of the above four species. Ryegrass seeds showed no germination on the 3rd day after imbibition in the presence of Grevillea seed coat extracts compared with 88% germination for the control. Thus, our results showed that seed coat is a major factor determining Grevillea seed dormancy and removal of seed coat dramatically increased seed germination. Grevillea seed coat extracts reduced seed germination and seedling growth of other species. We conclude that there is exogenous seed dormancy in Grevillea species and the chemical(s) in the seed coat is a major factor inhibiting seed germination.

Given the predicted changes in rainfall patterns for many Mediterranean climate regions, identifying seed tolerance to moisture stress in the earliest phase of plant development is an important consideration for species conservation, management and restoration. Here, we used polyethylene glycol (PEG 8000) to induce plant water deficit similar to drought stress in a field situation. Seeds of four Western Australia Banksia R.Br. (Proteaceae) species were incubated at seven levels of moisture potential (0 to −1.5 MPa) and three constant temperatures (10°C, 15°C and 20°C). In the absence of moisture stress, germination was uniformly high, but increasing drought stress led to reduced and delayed germination in all species. Overall, the threshold moisture potential value for a significant decline, and delay, in germination was –0.25 MPa. Results suggested that one species (B. coccinea) is likely to be most vulnerable to germination failure under predicted changes in rainfall patterns, whereas another (B. media) is likely to be less vulnerable. There was significant variation in population response to drought stress. However, this variation could not be explained by rainfall across species distributions. We discuss the PEG approach for assessing seed sensitivity to moisture stress, particularly in the context of shifting rainfall under climate change.

Species within the Macadamia genus (Proteaceae) are rare and threatened narrowly distributed inhabitants of subtropical lowland rainforests of eastern Australia. Despite their strong cultural links and economic importance as a source of germplasm for the macadamia nut industry, a comprehensive assessment of factors contributing to their conservation status, or the potential impacts of climate change, is lacking. We used maximum entropy models to identify the respective niche of the following three Macadamia species with overlapping extant distributions: M. integrifolia, M. ternifolia and M. tetraphylla. We used model predictions to identify and prioritise respective areas of habitat, together with change in geographic distribution of habitats between 1990 and 2070 climates. Results reveal considerable overlap in the geographic extent of habitat among the three species; however, the extent of current occupation of habitat by any individual species is limited. Relatively high levels of clearing of ecological communities strongly associated with M. integrifolia or M. ternifolia have occurred within the extent of their respective habitats, with M. tetraphylla less affected within the Queensland extent of its range. Response to climate change varies among the three species, with a general trend of shift in respective niche to areas that currently experience relatively high precipitation and lower temperature regimes.

Serotiny is a mechanism for storing propagules on plants, so that seed dispersal can be maximised after the death of aerial parts of plants or to take advantage of conditions beneficial to establishment. In fire-prone vegetation, regeneration of new plants after fire is mostly from seeds that are stored in the soil or on the plant. These traits are generally consistent within a genus. However, in Conospermum, a genus of shrubs that mostly occur in fire-prone vegetation and in which most species have soil-stored seeds, two species exhibit an unusual serotinous structure. We examined the morphology and anatomy of inflorescences and infructescences of C. capitatum and C. petiolare that were collected from natural vegetation in south-western Western Australia. Inflorescence and infructescence axes were sectioned and examined microscopically, fresh infructescences were heated in an oven to various temperatures for 2 min and the fruits from them sown in a germination trial. Some fruits were also treated with smoke chemicals. Both species have a low, dense growth form and retain the seed-like fruits in a serotinous structure formed by enlargement of the cortical cells of the inflorescence axis after flowering. The fruits can be effectively released from the plant only if the foliage is removed by a fire. For both species, the infructescence protects the fruits from heat up to 200°C for 2 min and this is similar to protection afforded by woody cones in other serotinous species. C. capitatum requires either heat or smoke to cue germination, whereas C. petiolare requires no cue, as is found in most other serotinous species. A combination of morphological modification associated with allometry of the whole plant body and physiological changes to germination requirements shows that a series of complex changes may be needed to develop serotiny from non-serotinous antecedents.

Adaptive radiation and reproductive isolation can determine the biogeographic structure of any species. We examine patterns of biotic variation in Embothrium coccineum, a Proteaceae tree that spans 20º of latitude and is both morphologically and genetically highly variable. We aim to: (1) explore the correspondence between these biotic patterns and current geographic and climatic gradients, and (2) determine whether and how those patterns are likely to respond to changing climate. We conducted separate Principal Components Analysis on biotic and abiotic sets of variables for 34 populations of Embothrium coccineum, accounting for a large fraction of the total variation in each. We then used canonical correlation analyses to optimize the match of those gradients onto each other. Smaller, rounder leaves and particular alleles typify the colder-drier parts of the range, while larger, lanceolate leaves and other alleles typify warmer-moister areas. Finally we mapped biotic profiles onto a predicted climatic landscape, based on doubling of CO2 projections. The climatic regime is predicted to shift geographically, but this lineage has successfully responded to repeated and dramatic climatic shifts since the Oligocene, and it should also be able to move and adapt quickly enough to meet the present challenge. More generally, our analytic approach can be extended to analysis of biotic and abiotic patterns in other species facing climatic challenges. Where there is enough biogeographic variation to provide adaptively relevant substrate, and where propagule dispersal is sufficiently extensive to keep up with the pace of spatial climatic shift, such taxa should be able to cope with shifting climate. Fil: Souto, Cintia Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentina Fil: Smouse, Peter E.. Rutgers University. Department of Ecology, Evolution and Natural Resources; Estados Unidos

Macadamia integrifolia Maiden & Betche and M. tetraphylla L.A.S.Johnson, and their hybrids, are cultivated for their edible kernels (mature embryos). Some kernels separate into halves (cotyledons) during post-harvest handling, and embryo cuticular characteristics may influence breakage. Some kernels have a gap between cotyledons before nut cracking, and this anatomical feature may be related to breakage. Kernels from cultivars producing high or low frequency of breakage were examined by transmission electron microscopy and scanning electron microscopy to identify differences in inner-cuticular wax. Whole seeds of each cultivar were opened without cracking to measure gaps between cotyledons and determine relationships between gaps and embryo breakage. Kernels from cultivars with low frequency of breakage had inner-epicuticular wax layers that were of the sculptured crust type whereas those of cultivars with high frequency of breakage were mainly of a wax-film type. Gap width and length of kernels separate at nut opening were more than twice those for intact kernels. There was a negative relationship between whole-kernel percentage and gap width between cotyledons.

Although pubescence has traditionally been considered to be related to the water economy of plants, the results are ambivalent and vary between different species. We tested two contrasting hypotheses for the functional significance of leaf pubescence of Proteaceae species from the Cape Floristic Region. First, we hypothesised that pubescence is a xeromorphic trait that conserves water by increasing the boundary layer resistance to diffusion. Water loss was measured in two morphotypes of Leucospermum conocarpodendron (L.) Buek that differ in the degree of leaf pubescence, using both gas exchange and gravimetric techniques. Pubescence contributed less than 5% of total leaf resistance and pubescent leaves transpired at least as rapidly as glabrous leaves due to having larger numbers of small stomata per leaf area. Although pubescence was not associated with drier sites in L. conocarpodendron, there was a weak negative correlation between rainfall and pubescence across 18 other Proteaceae species. We also hypothesised that pubescence is a radiation-protective trait. We assessed the effect of pubescence on light reflectance, leaf temperature, fluorescence and gas exchange characteristics in situ. Pubescent leaves of L. conocarpodendron were 19.2 ± 0.08% more reflective than glabrous leaves and had significantly greater pre-dawn photochemical efficiency. There was a positive association between leaf pubescence and habitat temperature in Proteaceae. We conclude that although pubescence is unlikely to be a xeric adaptation, it could serve a role in reducing photoinhibition and heat loading in Proteaceae species.

At least seven foliar taxa of Proteaceae occur in Oligo–Miocene lignite from the Newvale site. These taxa include two new species of the fossil genus Euproteaciphyllum, and previously described species of tribe Persoonieae and Banksia. Other specimens from Newvale are not assigned to new species, but some conform to leaves of the New Caledonian genus Beauprea, which is also represented in the lignite by common pollen. Two other Euproteaciphyllum species are described from the early Miocene Foulden Maar diatomite site. One of these species may belong to Alloxylon (tribe Embothrieae) and the other to tribe Macadamieae, subtribe Gevuininae. Ecologically, the species from Newvale represented important components of wet, oligotrophic, open vegetation containing scleromorphic angiosperms and very diverse conifers. In contrast, Proteaceae were large-leaved and rare in Lauraceae-dominated rainforest at the volcanic Foulden Maar site. Overall, the Oligo–Miocene fossils confirm that Proteaceae was formerly much more diverse and dominant in the New Zealand vegetation, and provide fossil evidence for biome conservatism in both leaf traits and lineage representation.

In wet sclerophyll forests seedling recruitment either occurs after intermittent fire events or continuously during intervals between fires in gaps created by small-scale disturbances. The dormancy and dispersal characteristics of seeds will influence how plant species exploit these contrasting recruitment opportunities. For example, long-lived seed banks may be crucial for persistence of species that are unable to recruit during intervals between fires if the length of fire intervals exceeds the life span of standing plants (senescence risk). To better understand mechanisms of population persistence during prolonged absence of fire in montane wet sclerophyll forests, we studied seed bank dynamics in four understorey species. We chose two species thought to have fire event-driven recruitment, Banksia integrifolia subsp. monticola (Proteaceae) and Goodia lotifolia (Fabaceae), and two species that are thought to have canopy gap-phase recruitment, Trochocarpa laurina (Ericaceae) and Tasmannia stipitata (Winteraceae). We measured seed rain, seed bank density and used seeds buried in nylon mesh bags to estimate rates of seed decay in the soil over time. All species produced a substantial seed crop on an annual basis. The annual seed crop in three species (G. lotifolia, T. stipitata and T. laurina) was released in a dormant state and developed a persistent seed bank, while one species (B. integrifolia) lacked dormancy and rapidly germinated under laboratory and field conditions. Seed bank characteristics of G. lotifolia appear to promote episodic recruitment after large landscape-scale fires, those of B. integrifolia appear to promote more continuous recruitment in response to smaller fires and other disturbances that avoid widespread mortality of established plants, while seed bank characteristics of T. stipitata and T. laurina may facilitate both episodic and continuous recruitment under respective types of disturbance. The four species appeared to have varied vulnerabilities and mechanisms for reducing immaturity risk and senescence risk to persistence of their populations under recurrent disturbance. Dormancy, seed bank longevity and seed rain are likely to be useful syndromes for predicting the response of wet sclerophyll forest understorey species to changed disturbance regimes.

Pollen protoplasts may supply important nutritional resources for birds; however, they are locked up within the mechanically strong and biochemically complex pollen wall. Previous studies of pollen digestion in birds have yielded highly variable and often contradictory results. We tested whether these differences could reflect the vastly different methodologies that have been used. We used a standard method to investigate digestion of Banksia grandis (Proteaceae) pollen in New Holland honeyeaters (Phylidonyris novaehollandiae). Four types of B. grandis pollen were examined: fresh, frozen for a week, stored in conditions to stimulate pregermination for 24 h, or collected by honeybees. Our data indicate that although pollen treatment may influence digestibility of the pollen grains, these differences do not reach statistical significance because they are dwarfed by a high degree of variability between birds fed the same diet as well as variability in gut transit time (generally more pollen grains were digested over longer transit times). Similar patterns were observed for red wattlebirds (Anthochaera carunculata) fed bee-collected pollen. We believe that feeding behaviour or gut transit time may explain the marked differences between previous studies of pollen digestion by nectarivores, particularly the conflicting results for New Holland honeyeaters.

Diverse Cenozoic (possibly latest Oligocene to mid–late Miocene) macrofossils from the Lightning Ridge opal fields are illustrated and discussed. Specimens identified to, or closely comparable with, extant taxa include ferns (Lygodium, Gleichenia and others), conifers now extinct in Australia (Dacrydium, Retrophyllum and Papuacedrus), Lauraceae (Cryptocarya/Cinnamomum), sclerophyllous Proteaceae (Banksia, Lomatia and Grevillea), Cunoniaceae/Elaeocarpaceae and Eucalyptus (and/or other Myrtaceae). Overall, at least four fern, three conifer and 30 angiosperm taxa are recognised. The climate supported many species with close relatives in wet Australasian habitats, including rainforests. However, a drier or more seasonal (?monsoonal) aspect is especially indicated by the presence of lobed leaves that resemble extant species of Brachychiton (Malvaceae), Erythrina (Fabaceae) and tribe Cercideae (Fabaceae). A degree of water stress is also suggested by the prevalence of narrow, toothed and/or deeply lobed angiosperm leaves.

In southern New South Wales, a suite of widespread plant species exhibit short-statured ‘dwarf’ growth forms on coastal headlands. It is unclear whether such populations are genetically distinct or whether dwarfism is a plastic response to the environment. We used four microsatellite markers to assess genetic differentiation among populations from coastal and inland sites for Banksia spinulosa var. spinulosa. We sampled plants from six locations, including from three ‘dwarf’ and three ‘normal’ populations. Mean levels of genetic diversity were slightly higher in the forest (Na = 7.07 ± 0.25; He = 0.80 ± 0.09) than on the coast (Na = 5.92 ± 0.70; He = 0.72 ± 0.10). In general, populations displayed genotypic diversity expected for outcrossed sexual reproduction, with 161 of 172 individuals displaying unique genotypes and mean values of FIS close to zero. However, we found evidence of at least limited clonal replication in each of four populations and, within one coastal population, 11 of 27 individuals displayed one of three replicated genotypes, implying that the effective population size may be considerably smaller than would be inferred from the number of plants at this site. Relative to studies with other Proteaceae, this set of populations showed low, although significant, levels of differentiation (global FST = 0.061; P

Fossils from the Newvale lignite mine, Southland, are the first substantiated foliar records of Proteaceae subfamily Persoonioideae. The fossils possess very large stomata, a probable synapomorphy for Persoonioideae, and within Proteaceae the combination of this feature and more or less parallel-aligned, brachyparacytic stomatal complexes and undulate anticlinal epidermal cell walls is uniquely found in this subfamily. The new genus Persoonieaephyllum is described to recognise affinity of the fossil leaves and cuticles with tribe Persoonieae of Persoonioideae and their distinction from its only other extant representative, Placospermum. Two new species are described. P. ornatum is represented by linear leaves less than 20 mm wide and possessing more or less parallel-aligned major veins. These leaves closely match those of extant hypostomatic, broad-leaved species of tribe Persoonieae and are distinct from Placospermum in venation and several cuticular details. P. villosum has so far been recovered only as cuticular material in disaggregated lignite. It is distinct from P. ornatum in having abundant trichome bases, an absence of surface tubercules, and even larger stomata (guard cells often >70 μm long). The fossils extend the known record of Persoonioideae in the New Zealand–New Caledonia region by ~20 million years.

Hakea myrtoides Meisn. is an attractive shrub that has a restricted distribution in the south-west of Western Australia. It is not killed by fire but re-sprouts from basal lignotubers. Its leaves are often severely affected by tar spot disease, caused by the biotrophic, stromatic ascomycete Phyllachora grevilleae (Lév.) Sacc. subsp. grevilleae (Lév) Sacc. This disease is spread by ascospores that are produced during the wettest months of the year: late autumn, winter and spring. Badly infected populations of H. myrtoides were burnt, either in a controlled burn in November 2007, or in a wildfire in January 2008. The incidence of tar spot disease on leaves of burnt plants in 2008 and 2009 was 4.4%, while its incidence on unburnt plants was significantly higher (25.1%). The incidence of flowering in 2009 was similar in both burnt and unburnt populations. Tar spot disease is common on H. myrtoides; it is present on 77% of collections of this host in the Western Australian Herbarium (PERTH).

Involucral leaves of Leucadendron have the remarkable ability to turn yellow upon flowering and regreen naturally as the florets of the inflorescence wilt. This colour change results from degradation of chlorophyll and to a lesser degree carotenoids, resulting in the unmasking of yellow colour. Chlorophyll levels were restored upon regreening. Degreening coincided with the complete dismantling of the thylakoid system, while keeping the outer plastid envelope intact. Regreening resulted from the complete redifferentiation of these gerontoplast-like plastids into functional chloroplasts. The colour change was directly linked to the development of the inflorescence. Complete removal of the inflorescence before flowering prevented the colour change while removal at full bloom, when involucral leaves were yellow, resulted in significantly faster regreening. This designates the inflorescence or florets as the possible origin of the colour change trigger and suggests that the colour change is involved with attraction of pollinators. Degreening and regreening also took place in a growth chamber under continuous high light intensity. Therefore neither pollination nor the presence of roots is required for regreening. It appears that colour change in Leucadendron results from a well-regulated degradation and subsequent synthesis of photosynthetic pigments.

Prescribed burning is applied worldwide as a forest management tool. It is broadly accepted that altered fire regimes can directly impact upon community structure and composition, but little is known about the indirect effects of altered fire regimes on the mechanisms that produce community-level changes such as changes to the reproductive output of individual plants, hence populations. We examined the reproductive output of four species of Proteaceae within a long term study site where disturbance histories for the last twenty years have been accurately recorded on 216 plots. Frequent fire was found to increase woody fruit production in Banksia marginata, but had no apparent effect on B. serrata, Hakea eriantha or H. sericea. Results of this study vary from a similar study which examined the effect of wildfires. The differences observed are likely to reflect the differing impacts of fire intensity on these species. Indirect changes in fruit production may result in changes in reproductive success of species which in turn may affect vegetation community structure and faunal habitat.

We examined the relationship between shoot growth and temperature and solar radiation in macadamia (Macadamia integrifolia Maiden and Betche, M. integrifolia × tetraphylla Johnson) as an aid to developing pruning strategies for this crop. Trees growing at Alstonville (28.9°S) in northern NSW, Australia, were pruned at various times to promote vegetative flushing under a range of environmental conditions. Flush development in macadamia is cyclic: bud release and stem elongation followed by a period of dormancy, before bud release of the subsequent flush. The rate of bud release after pruning was best correlated with the product of the mean temperature and solar radiation (r2 = 0.75, P

The incidence of kernel brown centres in macadamia (Macadamia integrifolia and M. tetraphylla and hybrids) has increased substantially in Australia. Although the defect amounts to only ~1% of all kernels processed in Australia, it costs the macadamia industry over AU$2 million per annum. Little formal research has been conducted, although the defect is mentioned widely in informal grower journals. Possible causal factors are reviewed in this article. Evidence suggests that kernel brown centres may be associated with exposure of enzymes in cell membranes and are also associated with incorrect nut-in-shell drying regimes. There appears to be an interaction among nut-in-shell moisture content, nut drying regime, and the incidence of brown centres. There is some indication that storage of wet nuts in poorly ventilated silos increases the potential for developing kernel brown centres. It is recommended that future research focusses on these issues.

Macadamia integrifolia Maiden & Betche (Proteaceae) from eastern Australia is farmed for its edible nuts and is capable of accumulating high foliar concentrations of manganese (Mn). It was investigated here in a pot trial, where a range of physiological responses to Mn treatment were measured. Although Mn uptake was initially slow, final foliar concentrations increased linearly with treatment levels. The highest observed mean foliar concentration of Mn was 7900 μg g–1 dry weight (dwt). No negative effect of Mn accumulation on plant growth was apparent, even at the highest treatment concentration. Two groups of plants, each exposed to either full sunlight or part shade were identically treated with Mn. At the highest treatment concentration of Mn, the mean foliar concentrations of Mn of the former group were found to be significantly higher than those of the latter. Because M. integrifolia is cyanogenic, leaf cyanogenic glycosides were quantified to test for a relationship between the known chemical defence strategy of cyanogenesis and a proposed one of Mn accumulation. However, further studies are required to clarify this. Quantitative organic acid analyses showed that oxalate ion may bind excess Mn in M. integrifolia leaves. That Mn is not accumulated in M. integrifolia fruit could render the species potentially useful for remediating Mn-affected soils long-term, while serving as a food crop.

The woody-fruited species Leucopogon propinquus R.Br., Styphelia tenuiflora Lindl. (Ericaceae) and Persoonia longifolia R.Br. (Proteaceae) need to be returned to restored mines in Western Australia. All species have physiological seed dormancy, however germination has been observed following the application of smoke to native habitats. We recorded seed viability, permeability to water, endocarp strength, morphology and germination ± gibberellic acid (GA3) every 3 months for 24 months of in-situ burial in the jarrah forest to determine the time of dormancy release and corresponding seed changes. The term ‘seed’ refers to the woody endocarp, plus the true seed. Persoonia longifolia reached 37% germination after burial in soil for 21 months, followed by chipping the endocarp and GA3 application. A minimum of 15 months soil burial was necessary for unchipped seeds to germinate; 22% germination was achieved after 18 months burial in soil followed by GA3 application. Viability of fresh seeds of all three species was 96–100% and remained unchanged for P. longifolia, but declined to 5 and 0% following 24 months of soil burial for L. propinquus and S. tenuiflora, respectively. Germination of the two Ericaceae species was negligible, despite the presence of viable seeds (30–63%, depending on the species) after 12 months of soil burial and substantial deterioration of the endocarp. To germinate large quantities of P. longifolia, for use in land restoration, drupes should be buried in-situ in forest soil for 18 months immediately following seed fall (early spring) and GA3 treated, following exhumation.

In south-western Australia, a rare plant community is found on shallow, winter-wet ironstone soils, which occur on coastal plains as isolated islands in a matrix of surrounding deeper sandy soils. To test for local adaptation of species endemic to these communities and potential inhibitory effects of ironstone soils on other species, we compared two rare ironstone Hakea species with four of their common congeners. The common congeners were chosen from nearby winter-wet habitats on deeper sandy soils and from non-wetland woodland habitats (i.e. two species in each habitat group). Seedlings of all species were grown on ironstone soil and subjected to waterlogging in a glasshouse experiment. Significant habitat-related differences emerged only when seedlings were waterlogged. When compared with their controls, shoot and root growth rates of ironstone endemics were less affected by waterlogging than those of their common congeners. This was partly associated with their large accumulation of leaf starch, and their substantial adventitious-root formation. Leaves of ironstone endemics also exhibited consistently higher concentrations of Cu and Zn. In contrast to the effect of waterlogging in the glasshouse experiment, natural waterlogging of seedlings transplanted into ironstone communities led to high mortality, but only in the non-wetland Hakea species. Mortality was strongly associated with the intensity of flooding events, with very small differences in inundation level (10–15 mm) strongly influencing seedling survival. Our results suggest that the chemistry of the waterlogged ironstone soil, and species adaptations to it, are important for understanding distribution patterns of these Hakea species.

The primary sequestration of foliar manganese (Mn) in Mn-hyperaccumulating plants can occur in either their photosynthetic or non-photosynthetic tissues, depending on the species. To date, only non-photosynthetic tissues have been found to be the major sinks in other hyperaccumulators. Here, electron (SEM) and proton (PIXE) microprobes were used to generate qualitative energy dispersive (EDS) X-ray maps of leaf cross sections. Two Mn hyperaccumulators, Garcinia amplexicaulis Vieill. (Clusiaceae) and Maytenus fournieri (Panch. and Sebert) Loesn. (Celastraceae), and the Mn accumulator Grevillea exul Lindley (Proteaceae) were studied. PIXE/EDS data obtained here for M. fournieri were in agreement with existing SEM/EDS data showing that the highest localised foliar Mn concentrations were in the epidermal tissues. However, this is the first in situ microprobe investigation of G. amplexicaulis and G. exul. The Mn X-ray maps of G. amplexicaulis revealed a previously undescribed third spatial distribution pattern among Mn-hyperaccumulating species. Manganese was relatively evenly distributed throughout the leaf photosynthetic and non-photosynthetic tissues, while in G. exul it was most highly concentrated in the epidermal cells.

There is a history of discrepancy in the interpretation of floral symmetry in the genus Banksia L.f. The variation arises not just from the potential nuances of symmetry terminology, as variation is also found in the diagrams that describe it. This paper clarifies the issue of the orientation of the ovaries within a Banksia unit inflorescence. Dissection of 2400 flowers in situ from four Banksia species has revealed the Banksia unit inflorescence to be enantiomorphic (having left-right asymmetry) due to the orientation of the ovaries. The asymmetry of the ovary and its pronounced development of the anterior side in fruit formation means that fruits are also readily distinguished as having arisen from either a left- or right-handed flower.

Dryandra sessilis (Knight) Domin. and Grevillea wilsonii A.Cunn. co-occur on lateritic soils in the jarrah forest of Western Australia, with their flowering seasons overlapping for several months during winter and spring. Both species are protandrous, with pollen presentation occurring 1–2 days before the stigmas of individual flowers become receptive. Peak receptivity, as indicated by maximum peroxidase secretion, coincides with the maximum opening of stigmatic grooves for D. sessilis or maximum elevation of the stigmatic papillae in G. wilsonii. Pollinators such as western wattlebirds, New Holland honeyeaters and western spinebills almost exclusively visit flowers or inflorescences at times when large amounts of nectar are present, and when self-pollen is available for transfer or stigmas are receptive to the deposition of pollen. By foraging in this manner, yet still moving frequently between plants and inflorescences, honeyeaters that visit D. sessilis should guarantee an effective spread of pollen. The overall level of fruiting success achieved by this species is considerably higher than that for G. wilsonii, a species whose flowers are visited much less often than those of D. sessilis. Allozyme analysis, artificial pollination experiments and the calculation of pollen : ovule ratios indicate that D. sessilis is essentially an obligate outcrosser, at least in locations where plant densities are high, whereas G. wilsonii has a mixed mating system that allows it to set fruits as a consequence of either selfing or outcrossing. Potential fruit-set is low for both species, with post-zygotic incompatibility mechanisms mediated by the availability of nutritional resources thought to be at least partly responsible for the even lower levels of final fruit-set. Total fruit and seed production by individual plants is much greater for D. sessilis than for G. wilsonii, and possibly a reflection of differences in the regeneration requirements of the two species after environmental disturbance such as fire.

The scarce fossil wood record of Proteaceae is complemented with the addition of a new morphogenus with two new species from the Oligocene of Patagonia, Scalarixylon patagonicum, gen. nov., sp. nov., and S. grandiradiatum, gen. nov., sp. nov. They become the first two fossil species that have all the typical characteristics of Proteaceae wood anatomy: wide multiseriate rays, tangential bands of vessels with unilateral banded associated parenchyma and simple perforation plates. They seem to be related to extant species that inhabit the subantarctic forests of Patagonia.

Phylogenies inferred from both chloroplast and nuclear DNA regions have placed the south-west Australian genus Dryandra R. Br. (93 spp.) among the descendents of the most recent common ancestor of the more widespread Australian genus Banksia L.f. (80 spp.). Here we consider the alternative solutions to maintaining monophyly at the generic rank and choose to make new combinations and replacement names for Dryandra in Banksia. We make the new combination Banksia ser. Dryandra in Banksia subgen. Banksia for 108 of the 109 new combinations at the ranks of species, subspecies, and variety and all 18 of the replacement names. We treat Banksia subgen. Banksia as the most inclusive clade that includes the type of Banksia (B. serrata) but not B. integrifolia. We erect Banksia subgen. Spathulatae to accommodate the species in the most inclusive clade that includes B. integrifolia but not B. serrata. These two subgenera of Banksia are equivalent to the clades informally called /Cryptostomata and /Phanerostomata elsewhere. We treat one of the new combinations, Banksia subulata, as incertae sedis within Banksia subgen. Banksia.

Univariate analysis (ANOVA) of waratah (Telopea speciosissima (Sm.) R.Br.) floral and leaf characters, chosen primarily for their horticultural importance, showed that there were detectable differences among populations and indicated, for most characters studied, that variation was greater among the tested natural populations than within. There were significant differences between some populations for all variables except inflorescence height. Inflorescence colour, particularly style colour, showed the greatest variation among populations and leaf margin type, leaf width and flower number were also variable. Inflorescence width, bract number, bract width, leaf length and leaf apex shape were variable within populations; however, they were less useful in distinguishing between populations. Multivariate analysis of characters (principle component analysis, PCA; or canonical variate analysis, CVA) showed unique character combinations in several of the populations studied. Natural waratah populations of this species can, therefore, be explored for unique, although subtle character variations for horticultural development. Conservation efforts should seek to maintain genetic diversity in natural populations and ensure that cultivated populations capture and maintain an appropriate level of diversity for continued selection and horticultural improvement.

Allozyme electrophoresis was used to measure and compare, with other members of the Proteaceae, levels and distribution of genetic diversity in Embothrium coccineum J.R.Forst., a widespread outcrossing species endemic of Andean Patagonian forests. We analysed variation at the species level by sampling 34 populations along its entire range of ~20° latitude. We tested the hypothesis of multiple Pleistocene refugia by phylogeographic methods. We resolved 16 isozyme loci assayed in 934 adult trees. At the species level, total genetic diversity (HT = 0.220) was similar to that of other outcrossed and widespread plant species. Genetic parameters (NA, PSS, HE) were not statistically different from other outcrossed but mostly range-restricted Proteaceae, reflecting a strong phylogenetic imprinting for species sharing life-history traits. Populations are genetically divergent among each other (FST = 0.202). The low correlation between geographic and genetic distances suggests separate histories, i.e. multiple glacial refugia for the cold-tolerant E. coccineum. Phylogeographic trees produced different topologies, although maximum likelihood and parsimony trees shared some elements. Both trees suggest a northern and central clade, and then a separate southern clade. Current processes such as gene flow and selection confound the historic signal. These results seem in contrast to many of the northern hemisphere post-glacial phylogeographic reconstructions which show clear historical tracks of northern range expansion from southern refugia. The present study highlights the importance of phylogenetic imprinting, life-history traits and historical events driving genetic diversity patterns in this widespread Proteaceae from southern South America.

This paper examines physiological characteristics of the leaves of Agastachys odorata R.Br., a wet-climate sclerophyllous shrub with very long-lived leaves. It addresses the hypothesis that cuticles become leakier to water vapour as leaves age. Astomatous cuticular conductance, whole-leaf minimum epidermal conductance, leaf damage and accumulation of epiphylls all increased several-fold with leaf age from first year growth to 10 years of age. Maximum carbon assimilation peaked 1 year after full leaf expansion, then declined. Intrinsic water use efficiency was highest in mid-aged leaves and declined markedly in the oldest leaves. Stomatal density, stomatal size and cuticle thickness did not vary significantly among ages. The older leaves were less effective at controlling water loss, resulting in decreases in water use efficiency. A differential increase in the conductance of the stomatal surface of the leaves relative to astomatous surface suggested that stomatal leakiness was significant in leaves over five years old. Although data for other species is ambiguous, the deterioration in A. odorata appears to be consistent with changes in the oldest leaves of other species. Thus, decreasing ability to use water efficiently appears to be a consequence of accumulated damage and may contribute to the need for leaf senescence in evergreen species with little self shading.

Macadamia nuts constitute an important part of the world nut industry and are highly valued for their health-promoting properties. Macadamia is an open-pollinated crop that takes 8–12 years to bear fruit when multiplied via seeds. The yield and nut quality in seedling plantations are often highly variable, and grafting is currently the most common method for producing nursery trees with reduced variability. We have previously reported on the tissue-culture propagation of macadamia, and in the present study we assessed the clonal integrity of the regenerated shoots. The RAPD profiles of 3 macadamia stock plants and 10 in vitro regenerated lines from each stock plant were analysed to assess the clonal integrity of the shoots regenerated in vitro for micropropagation purposes. The extent of genetic variation between the stock plants and 9 randomly selected seedlings was also assessed. There was no difference in clonal identity between the stock plants and their micropropagated progeny, indicating that clonal micropropagation was possible using enhanced axillary proliferation in macadamia. In contrast, there was a large genetic variation among the seedlings and between the seedlings and stock plants, with genetic distance estimates ranging from 0.121 to 0.637 among seedlings, indicating rampant out-crossing of the macadamia plant.

The Honey possum, Tarsipes rostratus, is an obligate nectarivore, known to feed on plant species from only three Families in south-western Western Australia: Myrtaceae, Proteaceae and Epacridaceae. These plants can be adversely affected by fire, decreased rainfall or groundwater levels and the pathogen Phytophthora cinnamomi. We investigated the ecology of T. rostratus in terms of: (i) how the population fluctuated in response to rainfall and fire over a 20-year period and (ii) changes in diet and movements during a period of decreased food availability in late summer. Mean capture rates were significantly positively correlated with mean flowering rates of Banksia ilicifolia over a 20-year period. Winter capture rates were also significantly positively correlated with both annual and winter rainfall two years prior to trapping in recently burnt areas, but not in long unburnt� areas. Capture rates were significantly higher in unburnt Banksia woodland during winter but densities there have declined since 1996, associated with the death of many Banksia ilicifolia trees from persistent Phytophthora infection. Notwithstanding this decline, winter capture rates in the unburnt areas were still approximately double those in the burnt areas 6 years after the last fire. Short-term capture rates were negatively correlated with barometric pressure, showing that movement and foraging is stimulated by the passage of low pressure frontal weather systems. Despite the paucity of known food sources flowering in late summer and autumn, there was no evidence of T. rostratus using plant species from other than the three above-noted Families. Utilisation areas in summer were also no larger than those previously recorded across all seasons in Scott National Park. Some individuals, however, moved extensive distances to locate spatially restricted food sources. The conservatism of their diet and the sensitivity of the population to changes in rainfall and fire history indicate that T. rostratus populations are particularly vulnerable to some of the environmental changes now occurring in south-western Australia.

Ectomycorrhizal (EM) associations facilitate plant nitrogen (N) acquisition, but the contribution of EM associations to tree N nutrition is difficult to ascertain in ecosystems. We studied the abilities of subtropical EM fungi and nutritionally contrasting Eucalyptus species, Eucalyptus grandis W.Hill ex Maiden and Eucalyptus racemosa Cav, to use N sources in axenic and soil cultures, and determined the effect of EM fungi on plant N use and plant 15N natural abundance (δ15N). As measured by seedling growth, both species showed little dependence on EM when growing in the N-rich minerotrophic soil from E. grandis rainforest habitat or in axenic culture with inorganic N sources. Both species were heavily dependent on EM associations when growing in the N-poor, organotrophic soil from the E. racemosa wallum habitat or in axenic culture with organic N sources. In axenic culture, EM associations enabled both species to use organic N when supplied with amide-, peptide- or protein-N. Grown axenically with glutamine- or protein-N, δ15N of almost all seedlings was lower than source N. The δ15N of all studied organisms was higher than the N source when grown on glutathione. This unexpected 15N enrichment was perhaps due to preferential uptake of an N moiety more 15N-enriched than the bulk molecular average. Grown with ammonium-N, the δ15N of non-EM seedlings was mostly higher than that of source N. In contrast, the δ15N of EM seedlings was mostly lower than that of source N, except at the lowest ammonium concentration. Discrimination against 15N was strongest when external ammonium concentration was high. We suggest that ammonium assimilation via EM fungi may be the cause of the often observed distinct foliar δ15N of EM and non-EM species, rather than use of different N sources by species with different root specialisations. In support of this notion, δ15N of soil and leaves in the rainforest were similar for E. grandis and co-occurring non-mycorrhizal Proteaceae. In contrast, in wallum forest, E. racemosa leaves and roots were strongly 15N-depleted relative to wallum soil and Proteaceae leaves. We conclude that foliar δ15N may be used in conjunction with other ecosystem information as a rapid indicator of plant dependency on EM associations for N acquisition.

Macadamia (Macadamia integrifolia) is a recurrent flushing tree, with buds alternating between growth and quiescence. Here we report on factors governing bud release. We used staggered tip-pruning (equivalent to branch decapitation) to generate a range of trees with different flush maturities, but uniform maturity within any given canopy. We then tip-pruned the trees again to remove the most recent flush, and monitored the time taken for visible axillary bud emergence. New flushes appeared 9–16 days after tip-pruning. The slowest bud emergence was associated with flushes of intermediate maturity, approximately 7 weeks old. Overall, the variation in bud emergence was most closely related to the growth rate of the most recent flush at the time of pruning, and not related to the levels of stored carbohydrates.

Blue-flowered Conospermum species are endemic to Western Australia, and are highly sought after in the horticulture industry. Aspects of the reproductive biology of several species were investigated. The paniculate inflorescences of Conospermum eatoniae E.Pritz. contain 6–10 florets; however, the uppermost two or three florets never open and only the basal one or two florets in an inflorescence set seed. When insect pollinators are excluded, flowers do not self-pollinate and set seed. Stigma receptivity occurred for up to 6 days following triggering of the style and was variable between C. eatoniae, C. amoenum Meisn. subsp. amoenum, C. caeruleum R.Br. and C. brownii Meisn. Hand-pollination with 10 pollen genotypes and two maternal C. eatoniae parents showed that although pollen tubes were observed in the style, no seed was set. Genetic analysis of open-set seed progeny showed that C. eatoniae outcrossed infrequently when grown in clonal rows in a plantation, but outcrossing was common in wild plants. This study demonstrates that the reproductive biology of blue-flowered Conospermum is complex and requires further investigation if the species are to be widely cultivated for horticulture.

Myxomycetes on the bark of dead Banksia attenuata and B. menziesii from the Perth metropolitan area of Western Australia were surveyed by the moist chamber technique, to determine whether the flora was similar on both hosts and what were the most important variables that determined the distribution of the most common species. Twenty-seven species of myxomycetes were recovered, including six new records for Australia (Comatricha rigidireta, Echinostelium elachiston, Paradiacheopsis cf. cribrata, P. rigida, Stemonitopsis amoena and S. cf. hyperopta). Members of the order Stemonitales comprised the largest number of species, whereas members of the Liceales occurred on the most bark pieces. The most common species were Licea kleistobolus, Echinostelium minutum, Comatricha elegans, Cribraria minutissima and Paradiacheopsis fimbriata. Overall, B. menziesii and B. attenuata had very similar myxomycete productivity, diversity and species assemblage, as did the tops and bottoms of the logs. It was concluded that they provided very similar microhabitats for myxomycetes. Both pH and the relative moisture content of the bark had an effect on myxomycete productivity. Bark decomposition level, pH and bark surface (top or bottom) were the most important variables determining the distribution of the most common myxomycete species.

Banksia (80 spp.; Proteaceae) has undergone extensive speciation and adaptive radiation on the island continent of Australia. Its members range from prostrate shrubs in the dry, infertile sandplains to 25 m tall trees in the loams of river margins, and they display striking variation in their fire survival strategies and floral and foliar morphologies. We examine the weight of both previously published (most trnL intron, trnL/F spacer, and rpl16 intron data) and new (matK, atpB, and waxy data, as well as most ITS data) DNA sequence evidence for the paraphyly of Banksia with respect to a monophyletic Dryandra (93 spp.). The nuclear waxy gene appears to be at two loci in the Proteaceae, and sequences presumably from the same locus resolve Banksia as paraphyletic with respect to Dryandra. The waxy and combined chloroplast DNA (cpDNA) data reject the monophyly of Banksia at a threshold of P = 0.05 using the winning sites and Kishino–Hasegawa tests. We consider this result and the repeated placement of Dryandra in the same clade (/Cryptostomata) of Banksia with each separate analysis of the DNA datasets (cpDNA, ITS, and waxy), to be strong molecular support for the paraphyly of Banksia with respect to Dryandra. The morphological synapomorphy of beaked follicles for /Cryptostomata (including Dryandra) reinforces this conclusion. We argue that realignment of taxa to produce one or more monophyletic genera is best attained by moving the taxa of Dryandra to Banksia. This would produce an easily recognised genus Banksia with four morphological synapomorphies. It would also probably confer some of the research attention garnered by the adaptive radiation of Banksia to the under-studied taxa of Dryandra, for Dryandra makes the radiation of Banksia even more remarkable.