May T.W.,Royal Botanic Gardens Melbourne |
Robinson R.M.,Brain Street |
Bell T.L.,University of Sydney |
Lebel T.,Royal Botanic Gardens Melbourne |
And 3 more authors.
Australian Journal of Botany | Year: 2011
Fungi are essential components of all ecosystems in roles including symbiotic partners, decomposers and nutrient cyclers and as a source of food for vertebrates and invertebrates. Fire changes the environment in which fungi live by affecting soil structure, nutrient availability, organic and inorganic substrates and other biotic components with which fungi interact, particularly mycophagous animals. We review the literature on fire and fungi in Australia, collating studies that include sites with different time since fire or different fire regimes. The studies used a variety of methods for survey and identification of fungi and focussed on different groups of fungi, with an emphasis on fruit-bodies of epigeal macrofungi and a lack of studies on microfungi in soil or plant tissues. There was a lack of replication of fire treatment effects in some studies. Nevertheless, most studies reported some consequence of fire on the fungal community. Studies on fire and fungi were concentrated in eucalypt forest in south-west and south-eastern Australia, and were lacking for ecosystems such as grasslands and tropical savannahs. The effects of fire on fungi are highly variable and depend on factors such as soil and vegetation type and variation in fire intensity and history, including the length of time between fires. There is a post-fire flush of fruit-bodies of pyrophilous macrofungi, but there are also fungi that prefer long unburnt vegetation. The few studies that tested the effect of fire regimes in relation to the intervals between burns did not yield consistent results. The functional roles of fungi in ecosystems and the interactions of fire with these functions are explained and discussed. Responses of fungi to fire are reviewed for each fungal trophic group, and also in relation to interactions between fungi and vertebrates and invertebrates. Recommendations are made to include monitoring of fungi in large-scale fire management research programs and to integrate the use of morphological and molecular methods of identification. Preliminary results suggest that fire mosaics promote heterogeneity in the fungal community. Management of substrates could assist in preserving fungal diversity in the absence of specific information on fungi. © 2011 CSIRO.
Barker W.R.,State Herbarium of South Australia |
Barker W.R.,University of Adelaide |
Cockerton G.T.B.,Bassendean Delivery Center
Nuytsia | Year: 2011
Stackhousia stratfordii W.R.Barker & Cockerton sp. nov. possesses attributes unique to its genus and subfamily of opposite sub-radical leaves and flowers borne in scapes and containing three stamens. Morphological evidence is summarised arguing its placement within Stackhousia.
Mast A.R.,Florida State University |
Milton E.F.,Florida State University |
Jones E.H.,Florida State University |
Barker R.M.,State Herbarium of South Australia |
And 3 more authors.
American Journal of Botany | Year: 2012
• Premise of the study: A past study based on morphological data alone showed that the means by which plants of the Australian genus Hakea reduce florivory is related to the evolution of bird pollination. For example, bird pollination was shown to have arisen only in insect-pollinated lineages that already produced greater amounts of floral cyanide, a feature that reduces florivory. We examine a central conclusion of that study, and a common assumption in the literature, that bird pollination arose in insect-pollinated lineages, rather than the reverse. • Methods: We combined morphological and DNA data to infer the phylogeny and age of the Australian genus Hakea, using 9.2 kilobases of plastid and nuclear DNA and 46 morphological characters from a taxonomically even sampling of 55 of the 149 species. • Key results: Hakea is rooted confidently in a position that has not been suggested before. The phylogeny implies that bird pollination is primitive in Hakea and that multiple shifts to insect pollination have occurred. The unexpectedly young age of Hakea (a crown age of ca. 10 Ma) makes it coincident with its primary bird pollinators (honeyeaters) throughout its history. • Conclusions: Our study demonstrates that Hakea is an exception to the more commonly described shift from insect to bird pollination. However, we note that only one previous phylogenetic study involved Australian plants and their honeyeater pollinators and that our finding might prove to be more common on that continent. © 2012 Botanical Society of America.
Christmas M.J.,University of Adelaide |
Biffin E.,State Herbarium of South Australia |
Breed M.F.,University of Adelaide |
Lowe A.J.,University of Adelaide
Molecular Ecology | Year: 2016
Teasing apart neutral and adaptive genomic processes and identifying loci that are targets of selection can be difficult, particularly for nonmodel species that lack a reference genome. However, identifying such loci and the factors driving selection have the potential to greatly assist conservation and restoration practices, especially for the management of species in the face of contemporary and future climate change. Here, we focus on assessing adaptive genomic variation within a nonmodel plant species, the narrow-leaf hopbush (Dodonaea viscosa ssp. angustissima), commonly used for restoration in Australia. We used a hybrid-capture target enrichment approach to selectively sequence 970 genes across 17 populations along a latitudinal gradient from 30°S to 36°S. We analysed 8462 single-nucleotide polymorphisms (SNPs) for FST outliers as well as associations with environmental variables. Using three different methods, we found 55 SNPs with significant correlations to temperature and water availability, and 38 SNPs to elevation. Genes containing SNPs identified as under environmental selection were diverse, including aquaporin and abscisic acid genes, as well as genes with ontologies relating to responses to environmental stressors such as water deprivation and salt stress. Redundancy analysis demonstrated that only a small proportion of the total genetic variance was explained by environmental variables. We demonstrate that selection has led to clines in allele frequencies in a number of functional genes, including those linked to leaf shape and stomatal variation, which have been previously observed to vary along the sampled environmental cline. Using our approach, gene regions subject to environmental selection can be readily identified for nonmodel organisms. © 2016 John Wiley & Sons Ltd
Ndlovu J.,Stellenbosch University |
Richardson D.M.,Stellenbosch University |
Wilson J.R.U.,Stellenbosch University |
Wilson J.R.U.,South African National Biodiversity Institute |
And 2 more authors.
Annals of Botany | Year: 2013
Background and AimsUnderstanding the introduction history of invasive plant species is important for their management and identifying effective host-specific biological control agents. However, uncertain taxonomy, intra-and interspecific hybridization, and cryptic speciation may obscure introduction histories, making it difficult to identify native regions to explore for host-specific agents. The overall aim of this study was to identify the native source populations of Acacia pycnantha, a tree native to south-eastern Australia and invasive in South Africa, Western Australia and Portugal. Using a phylogeographical approach also allowed an exploration of the historical processes that have shaped the genetic structure of A. pycnantha in its native range.MethodsNuclear (nDNA) and plastid DNA sequence data were used in network and tree-building analyses to reconstruct phylogeographical relationships between native and invasive A. pycnantha populations. In addition, mismatch distributions, relative rates and Bayesian analyses were used to infer recent demographic processes and timing of events in Australia that led to population structure and diversification.Key ResultsThe plastid network indicated that Australian populations of A. pycnantha are geographically structured into two informally recognized lineages, the wetland and dryland forms, whereas the nuclear phylogeny showed little geographical structure between these two forms. Moreover, the dryland form of A. pycnantha showed close genetic similarity to the wetland form based on nDNA sequence data. Hybrid zones may explain these findings, supported here by incongruent phylogenetic placement of some of these taxa between nuclear and plastid genealogies.ConclusionsIt is hypothesized that habitat fragmentation due to cycles of aridity inter-dispersed with periods of abundant rainfall during the Pleistocene (approx. 100 kya) probably gave rise to native dryland and wetland forms of A. pycnantha. Although the different lineages were confined to different ecological regions, we also found evidence for intraspecific hybridization in Victoria. The invasive populations in Portugal and South Africa represent wetland forms, whereas some South African populations resemble the Victorian dryland form. The success of the biological control programme for A. pycnantha in South Africa may therefore be attributed to the fact that the gall-forming wasp Trichilogaster signiventris was sourced from South Australian populations, which closely match most of the invasive populations in South Africa. © 2013 The Author.
Kolesik P.,Bionomics |
Barker W.R.B.,State Herbarium of South Australia |
Barker W.R.B.,University of Adelaide
Australian Journal of Entomology | Year: 2013
Dasineura gannoniKolesik sp. nov. is the first gall midge species known to feed on plants from the Hakea-Grevillea generic alliance. D.gannoni induces galls on swamp-loving Hakea microcarpaR. Br. and H.nodosaR. Br., flowering plant shrubs naturally occurring in south-east mainland Australia and Tasmania. The gall is a conspicuous red-coloured, multi-chambered, leaf swelling containing one, occasionally two, red larvae in each chamber. Pupation takes place in the soil. The new species was originally identified on H.microcarpa near Thredbo River in New South Wales. Later examination of herbarium vouchers found presence of galls of the new species on further specimens of H.microcarpa and another swamp-loving species H.nodosa. The geographical range of the new species extends over much of the combined distribution area of the two host plants on mainland Australia from far south-east Queensland through east New South Wales to Victoria and south-east South Australia. © 2013 The Authors © 2013 Australian Entomological Society.
Burge D.O.,Duke University |
Barker W.R.,State Herbarium of South Australia |
Barker W.R.,University of Adelaide
Australian Systematic Botany | Year: 2010
To elucidate the evolutionary origin of nickel (Ni) hyperaccumulation by the Australian serpentinite-endemic plant Stackhousia tryonii Bailey, phylogenetic analyses of chloroplast and nuclear DNA for Stackhousia and its close relatives were combined with assays of plant-tissue Ni concentrations. Thirty-five plants from 20 taxa were analysed by sequencing nuclear rDNA (ITS) and the plastid trnL-F region. Phylogenetic analysis of sequence data was conducted under maximum parsimony and Bayesian search criteria. In all, 100 plants from 39 taxa, including all 33 Stackhousia species, were analysed for Ni concentration by radial inductively coupled plasma atomic-emission spectrometry (ICP-AES). In phylogenetic analyses, S. tryonii was monophyletic, nested within a monophyletic Stackhousia. Only S. tryonii contained concentrations of Ni above the hyperaccumulation threshold (0.1%; 1000ppm), containing between 0.25% (2500ppm) and 4.1% (41000ppm) Ni by dry weight. Nickel-hyperaccumulation ability appears to have been acquired once during diversification of Stackhousia, by S. tryonii. © CSIRO.
Costion C.M.,James Cook University |
Costion C.M.,University of Adelaide |
Edwards W.,James Cook University |
Ford A.J.,CSIRO |
And 8 more authors.
Diversity and Distributions | Year: 2015
Aim: The plight of the world's biodiversity hotspots has been paralleled by a debate over how to best prioritize or maximize gain of biodiversity for conservation. Approaches to date have focused on quantifying species, habitat, phylogenetic or other types of diversity. The importance of preserving evolutionary distinctiveness or phylogenetic diversity (PD) has gained popularity due to its ability to identify evolutionary patterns in the landscape that traditional taxon richness measures cannot. Here, we expand upon the application of PD as a biodiversity index and incorporate data on historical biogeography to understand the processes that shaped the assembly of a tropical flora. Location: Tropical north-east Queensland, Australia. Methods: We generated a genus-level molecular phylogeny for the bioregion to calculate PD. We then integrated data on historical biogeography into a model to explain the distribution of PD and the PD residuals and further tested for a correlation between rain forest stability through time and community assembly. Results: We identified a strong correlation between PD residuals and the biogeographic origin of the lineages in the extant flora. Areas with higher PD than expected based on generic richness (GR) contain a higher proportion of immigrant plant lineages dispersed into northern Australia mostly from Southeast Asia within the past few million years. Areas with lower PD than predicted by genus richness are rich in ancient Australian relict lineages and are correlated with previously identified rain forest refugia that have remained stable throughout the last glacial cycle. Main conclusions: Maximizing PD without historical interpretation may yield unintended or undesirable conservation outcomes such as deprioritizing ancient refugia with lower PD values. By understanding the biome assembly of a region, better-informed decisions can be made to ensure different stages of a region's evolutionary history are preserved. © 2014 John Wiley & Sons Ltd.
PubMed | State Herbarium of South Australia and University of Adelaide
Type: Journal Article | Journal: Molecular ecology | Year: 2016
Teasing apart neutral and adaptive genomic processes and identifying loci that are targets of selection can be difficult, particularly for nonmodel species that lack a reference genome. However, identifying such loci and the factors driving selection have the potential to greatly assist conservation and restoration practices, especially for the management of species in the face of contemporary and future climate change. Here, we focus on assessing adaptive genomic variation within a nonmodel plant species, the narrow-leaf hopbush (Dodonaea viscosa ssp. angustissima), commonly used for restoration in Australia. We used a hybrid-capture target enrichment approach to selectively sequence 970 genes across 17 populations along a latitudinal gradient from 30S to 36S. We analysed 8462 single-nucleotide polymorphisms (SNPs) for FST outliers as well as associations with environmental variables. Using three different methods, we found 55 SNPs with significant correlations to temperature and water availability, and 38 SNPs to elevation. Genes containing SNPs identified as under environmental selection were diverse, including aquaporin and abscisic acid genes, as well as genes with ontologies relating to responses to environmental stressors such as water deprivation and salt stress. Redundancy analysis demonstrated that only a small proportion of the total genetic variance was explained by environmental variables. We demonstrate that selection has led to clines in allele frequencies in a number of functional genes, including those linked to leaf shape and stomatal variation, which have been previously observed to vary along the sampled environmental cline. Using our approach, gene regions subject to environmental selection can be readily identified for nonmodel organisms.
Chinnock R.J.,State Herbarium of South Australia |
Nuytsia | Year: 2011
Eremophila koobabbiensis Chinnock, sp.nov., is described and illustrated. This rare species is known only from one area north of Moora and its conservation is discussed. It is also established in cultivation and its long-term survival is assured.