Royal Botanic Gardens and Domain Trust

Sydney, Australia

Royal Botanic Gardens and Domain Trust

Sydney, Australia
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Morin L.,CSIRO | Aveyard R.,CSIRO | Lidbetter J.R.,Australian Department of Primary Industries and Fisheries | Wilson P.G.,Royal Botanic Gardens and Domain Trust
PLoS ONE | Year: 2012

The exotic rust fungus Puccinia psidii sensu lato was first detected in Australia in April 2010. This study aimed to determine the host-range potential of this accession of the rust by testing its pathogenicity on plants of 122 taxa, representative of the 15 tribes of the subfamily Myrtoideae in the family Myrtaceae. Each taxon was tested in two separate trials (unless indicated otherwise) that comprised up to five replicates per taxon and six replicates of a positive control (Syzygium jambos). No visible symptoms were observed on the following four taxa in either trial: Eucalyptus grandis×camaldulensis, E. moluccana, Lophostemon confertus and Sannantha angusta. Only small chlorotic or necrotic flecks without any uredinia (rust fruiting bodies) were observed on inoculated leaves of seven other taxa (Acca sellowiana, Corymbia calophylla 'Rosea', Lophostemon suaveolens, Psidium cattleyanum, P. guajava 'Hawaiian' and 'Indian', Syzygium unipunctatum). Fully-developed uredinia were observed on all replicates across both trials of 28 taxa from 8 tribes belonging to the following 17 genera: Agonis, Austromyrtus, Beaufortia, Callistemon, Calothamnus, Chamelaucium, Darwinia, Eucalyptus, Gossia, Kunzea, Leptospermum, Melaleuca, Metrosideros, Syzygium, Thryptomene, Tristania, Verticordia. In contrast, the remaining 83 taxa inoculated, including the majority of Corymbia and Eucalyptus species, developed a broad range of symptoms, often across the full spectrum, from fully-developed uredinia to no visible symptoms. These results were encouraging as they indicate that some levels of genetic resistance to the rust possibly exist in these taxa. Overall, our results indicated no apparent association between the presence or absence of disease symptoms and the phylogenetic relatedness of taxa. It is most likely that the majority of the thousands of Myrtaceae species found in Australia have the potential to become infected to some degree by the rust, although this wide host range may not be fully realized in the field. © 2012 Morin et al.


Summerell B.A.,Royal Botanic Gardens and Domain Trust | Leslie J.F.,Kansas State University
Fungal Diversity | Year: 2011

Fusarium is globally one of the most important genera of fungi, causing an array of plant diseases, producing mycotoxins and adversely affecting human health. The genus is taxonomically complex and accurate identification requires a suite of different morphological, biological and phylogenetic markers. Herein we review some of the major advances in our knowledge of Fusarium that have occurred over the past 50 years. © Kevin D. Hyde 2011.


Renner M.A.M.,Royal Botanic Gardens and Domain Trust
Telopea | Year: 2014

Seven species belonging to Radula subg. Radula are accepted for Australasia. Radula oreopsis M.A.M.Renner is described as new, while R. kurzii, R. multiflora, R. reflexa and R. sharpii are excluded from the region. Molecular and morphological data provide evidence suggesting that the broad species concepts recently applied to subg. Radula in Australia and across the Pacific are not useful. Many subtle yet consistent differences in size and shape, and in micromorphological and anatomical characters potentially inform species circumscription. However, most differences between species are virtually impossible to apprehend independent of molecular data corroborating their significance. Herbarium-based studies and the interpretation of type material are therefore challenging. However, the molecular phylogeny based on three chloroplast markers unites a morphologically heterogeneous array of individuals from across Australasia and the Pacific into a single fully supported clade containing individuals corresponding to the type of R. javanica as well as individuals from Australia, New Zealand and Fiji attributed by various workers to R. erigens, R. javanica, R. multiflora and R. reflexa. There is a general lack of congruence between morphological and molecular groups across the phylogeny. Morphologically similar individuals are resolved in different clades where they are more closely related to morphologically dissimilar species, which may hint at morphological convergence. Morphologically different individuals are nested within each other. The unique cell ornamentation in R. oreopsis, but not in other individuals (here attributed to other species) within the same clade is one example hinting at rapid morphological evolution. The dispersed nature of land within island archipelagos means spatial isolation could contribute to origin and maintenance of species diversity across the Pacific. Every habitat may be effectively peripherally isolated by dispersal limitation. If rates of dispersal and divergence are equivalent across the region, the Pacific and bounding lands including the Wet Tropics Bioregion could maintain species paraphyly in perpetuity.


Wilson K.L.,Royal Botanic Gardens and Domain Trust
Taxon | Year: 2016

Decisions are reported on: (1) 35 proposals to conserve and reject names recommended for acceptance in the Nomenclature Committee for Vascular Plants (NCVP) Report 65 and one proposal from Report 64; (2) 11 such proposals recommended for rejection in those Committee Reports; (3) one proposal was referred back to the NCVP for further consideration; (4) two conservation proposals for which the NCVP could not reach a firm recommendation; and (5) three recommendations from the NCVP on requests for binding decisions, one under Art. 38.4 (adequate description) and two under Art. 53.5 (confusingly similar names). © International Association for Plant Taxonomy (IAPT) 2016.


Renner M.A.M.,Royal Botanic Gardens and Domain Trust
Botanical Journal of the Linnean Society | Year: 2015

The quantification of lobule shape for Radula spp. shows that there is overlap in lobule shape space occupied by subgenera, such that lobule shape does not always reflect relationships. Morphological convergence caused by lineages repeatedly traversing shared regions of morphospace appears commonplace in Radula, and means that many pairs of relatively unrelated species have similar lobule shapes. When observed over time, as in comparisons between fossil and extant species, this may give the impression of stasis if fossil species resemble modern species by chance, independent of their relatedness. This poses a challenge to relating fossils of known age to extant lineages, particularly when fossils are sterile. Significant rate variation between lineages was identified by Adams' Q-mode analysis, with the fastest subgenus evolving 23 times more quickly than the slowest. Species of subgenus Volutoradula and subgenus Metaradula are apparently over-dispersed throughout lobule morphospace according to Sidlauskas' method; morphometric branch lengths and hypervolumes in other subgenera can be explained by a stochastic process. In contrast, Bayesian analysis of macroevolutionary mixtures (BAMM) identified a single evolutionary rate as having the highest posterior probability. Consideration of the three independent accessions into auriculate lobule morphospace by Cladoradula and Radula, wherein convergent lobule shapes result from convergent lobule ontogenies and are correlated with bipinnately branched shoot systems and robust primary stems, leads to an ontogenetic hypothesis driven by structural requirements for light interception, under which auriculate lobules are a spandrel. It is speculated that lobules themselves, however, may be a key innovation facilitating radiation into microsites devoid of or depauperate in fungal endophytes. © 2015 The Linnean Society of London.


Renner M.A.M.,Royal Botanic Gardens and Domain Trust
Polish Botanical Journal | Year: 2013

Lejeunea subelobata Carrington and Pearson has been regarded as a synonym of L. drummondii Taylor, but the two species differ in patterns of variation in lobule morphology, shapes of the gynoecial bracteole, female bract underleaf and vegetative underleaves; in stem anatomy, and ecology. Lejeunea subelobata is a rheophyte from south-east Australia, Tasmania, and New Zealand that grows primarily as a lithophyte on rock within and around waterways, in association with basicolous substrates particularly basalt, rhyolite and andesite. Lobules in L. subelobata are always explanate, the female bract underleaf is obovate, underleaves are rotund and remote, and the stem medulla has 19-26 cells with small concave trigones. Lejeunea drummondii is, in its current circumscription, an ecologically and morphologically malleable taxon confined to Australia. The relationship between L. drummondii and plants from New Zealand described as L. epiphylla Colenso nom. illeg. requires further investigation.


Wilson K.L.,Royal Botanic Gardens and Domain Trust
Taxon | Year: 2016

Revised procedures for the General Committee and the Permanent Nomenclatural Committees for particular groups are reported. Decisions are reported on: (1) two overlooked proposals from before the Melbourne Congress, one to conserve a name and the other to suppress a work; (2) thirty proposals to conserve and reject names recommended for acceptance in the Nomenclature Committee for Vascular Plants Report 64 and thirteen such proposals recommended for rejection in that Committee Report; (3) two conservation proposals for which the NCVP could not make a firm recommendation; (4) one recommendation from the NCVP to suppress a work; and (5) five recommendations from the NCVP on requests for binding decisions, four under Art. 38.4 (adequate description) and one under Art. 53.5 (parahomonymy). © International Association for Plant Taxonomy (IAPT) 2016.


Weston P.H.,Royal Botanic Gardens and Domain Trust
Methods in Molecular Biology | Year: 2014

Molecular systematics has revolutionized our understanding of the evolution of the Proteaceae. Phylogenetic relationships have been reconstructed down to generic level and below from alignments of chloroplast and nuclear DNA sequences. These trees have enabled the monophyly of all subfamilies, tribes, and subtribes to be rigorously tested and the construction of a new classification of the family at these ranks. Molecular data have also played a major part in testing the monophyly of genera and infrageneric taxa, some of which have been recircumscribed as a result. Molecular trees and chronograms have been used to test numerous previously postulated biogeographic and evolutionary hypotheses, some of which have been modified or abandoned as a result. Hypotheses that have been supported by molecular phylogenetic trees and chronograms include the following: that the proteaceous pattern of repeated disjunct distributions across the southern hemisphere is partly the result of long-distance dispersal; that high proteaceous diversity in south-western Australia and the Cape Floristic Region of South Africa is due to high diversification rates in some clades but is not an evolutionary response to Mediterranean climates; that the sclerophyllous leaves of many shrubby members of the family are not adaptations to dry environments but for protecting mesophyll in brightly illuminated habitats; that deeply encrypted foliar stomata are adaptations for minimizing water loss in dry environments; and that Protea originated in the Cape Floristic Region of South Africa and that one of its subclades has greatly expanded its distribution into tropical savannas. Reconstructing phylogeny down to species level is now the main goal of molecular systematists of the Proteaceae. The biggest challenge in achieving this task will be resolving species trees from numerous gene trees in complexes of closely related species. © 2014 Springer Science+Business Media New York.


Sommerville K.D.,Royal Botanic Gardens and Domain Trust | Offord C.A.,Royal Botanic Gardens and Domain Trust
Acta Horticulturae | Year: 2015

Seedbanking is an effective ex situ conservation technique for species with seeds that tolerate drying to 3-7% moisture content and long term storage at -20°C. However, it has been estimated that as many as 50% of rainforest species may produce seeds that do not tolerate desiccation; the remainder may tolerate desiccation but may not tolerate freezing or may be comparatively short-lived in storage at -20°C. We investigated freezing tolerance and comparative longevity in storage for 5 Australian rainforest trees with desiccation-tolerant seeds. Seeds stored at -20°C for 2 to 7 years were removed from storage, thawed and germinated on 0.7% agar at 20 or 25°C with a 12 h photoperiod. Seeds that had retained their viability following freezing (germination ≥84%) were rehydrated for two weeks at 20°C and 47% relative humidity then artificially aged at 43±2°C and 60% relative humidity. Seeds were withdrawn from the aging environment at intervals of 1, 2, 5, 9, 20 and 30 days and tested for their ability to germinate. The number of days in the aging environment required to reduce germination by 50% was estimated by Probit analysis in GenStat v11. Species found to be comparatively short-lived were further tested for their ability to tolerate cryopreservation (storage in LN vapour at -192°C) with no pre-treatment. Of the five species tested, only Archirhodomyrtus beckleri failed to germinate following freezing. Abrophyllum ornans tolerated freezing but storage for 7 years at -20°C reduced its germinability from 100 to 41%. The remaining three species - Caldcluvia paniculosa, Cuttsia viburnea and Quintinia verdonii - had retained viability following storage at -20°C for 2-3 years but proved to be comparatively short-lived under artificial aging conditions (p50<5 days) and therefore also likely to be short-lived in storage at the standard seedbanking temperature of -20°C. All three species tolerated storage for 1 week at -192°C with no significant reduction in germination percentage. Cryopreservation is likely to be the best option for long-term storage of both desiccation-sensitive and desiccation-tolerant seeds from rainforest regions.


Olde P.,Royal Botanic Gardens and Domain Trust
Acta Horticulturae | Year: 2015

The Hakeinae, a subtribe of Embothrieae, Proteaceae, consists of five genera, Buckinghamia, Opisthiolepis, Grevillea, Hakea and Finschia. The genera are discussed with respect to their suitability for horticulture and commerce. Particular reference is made to Buckinghamia celcissima, some new Grevillea cultivars, Grevillea 'Goliath' and Grevillea 'Bulli Beauty' and the Western Australian species (Grevillea eriobotrya) recently introduced to commercial use as cut flowers and garden subjects. Some observations are made on older cultivars, fertility, their cultivation, maintenance, breeding and utility as cut flowers or foliage.

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