Poczai P.,University of Pannonia |
Cseh A.,Hungarian Academy of Sciences |
Taller J.,University of Pannonia |
Symon D.E.,Plant Biodiversity Center
Plant Systematics and Evolution
The subgenus Archaesolanum is a group composed of eight species with a characteristic chromosome number based on n = x = 23 and an area restricted to the South Pacific. This subgenus is an isolated group of Solanum for which extensive information about phylogenetic relationships based on molecular genetic methods is lacking. This study represents an approach to analyze genetic relationships within this group. In this context, seven species were examined using random amplified polymorphic DNA (RAPD) markers. In further analysis, the amplification products of two chloroplast regions (trnS-trnG and rbcL) were studied with polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method. Screening for the presence of unique mitochondrial rearrangements was also carried out using universal mitochondrial primers for the detection of fragment length polymorphisms. We identified two major groups within the subgenus; one was composed of the members of ser. Avicularia and Laciniata, while the other was formed by species belonging to ser. Similia. It is suggested that the taxonomic status of series within the Archaesolanum clade should be revised. The hybrid origin of S. laciniatum was also tested, and two hypotheses regarding its phylogeny are assumed. © 2010 Springer-Verlag. Source
Nayar S.,South Australian Research And Development Institute |
Collings G.J.,South Australian Research And Development Institute |
Miller D.J.,Coast and Marine Conservation Branch |
Bryars S.,Plant Biodiversity Center |
Cheshire A.C.,Science to Manage Uncertainty Pty Ltd.
Marine Pollution Bulletin
Ecologically relevant estimates of seasonal variability in nitrogen uptake and allocation in two species of temperate seagrasses were obtained using in situ isotope-labelling approach. Significantly higher uptake rates of ammonium by leaves, roots and epiphytes of Amphibolis than Posidonia were observed. Overall, root uptake rates were lower than other components. Effect of season was not significant for leaves, roots or epiphytes of the two species. However, plankton uptake varied seasonally with higher rates in winter (0.98mgNg-1DWh-1). In contrast, nitrate uptake rates for various components were significantly affected by seasons. Uptake rates by plankton were highest ranging from 0.003mgNg-1DWh-1 (summer, Amphibolis) to 0.69mgNg-1DWh-1 (winter, Posidonia). Uptake of nitrate by roots was negligible. Biotic uptake rates for nitrate were an order of magnitude slower than ammonium, demonstrating an affinity for ammonium over nitrate as a preferred inorganic nitrogen source. Adelaide coastal waters have lost over 5000ha of seagrasses, much of this attributed to nutrient inputs from wastewater, industrial and stormwater. Managing these inputs into future requires better understanding of the fate of nutrients, particularly biological uptake. This study attempts to quantify uptake rates of nitrogen by seagrasses. © 2010 Elsevier Ltd. Source
Blair D.,James Cook University |
Mcmahon A.,James Cook University |
Mcdonald B.,James Cook University |
Mcdonald B.,Queensland University of Technology |
And 4 more authors.
Marine Mammal Science
We investigated phylogeography, demography, and population connectivity of the dugong (Dugong dugon) in Australian waters using mitochondrial control region DNA sequences from 177 Australian dugongs and 11 from elsewhere. The dugong is widespread in shallow Indo-West Pacific waters suitable for growth of its main food, seagrass. We hypothesized that the loss of habitat and creation of a land barrier (the Torres Strait landbridge) during low sea level stands associated with Pleistocene glacial cycles have left a persisting genetic signature in the dugong. The landbridge was most recently flooded about 7,000 yr ago. Individual dugongs are capable of traveling long distances, suggesting an alternative hypothesis that there might now be little genetic differentiation across the dugong's Australian range. We demonstrated that Australian dugongs fall into two distinct maternal lineages and exhibit a phylogeographic pattern reflecting Pleistocene sea-level fluctuations. Within each lineage, genetic structure exists, albeit at large spatial scales. We suggest that these lineages diverged following the last emergence of the Torres Strait landbridge (ca. 115 kya) and remained geographically separated until after 7 kya when passage through Torres Strait again became possible for marine animals. Evidence for population growth in the widespread lineage, especially after the last glacial maximum, was detected. © 2013 by the Society for Marine Mammalogy. Source
Dixon R.R.M.,Murdoch University |
Mattio L.,University of Cape Town |
Mattio L.,Labex Corail Institute Of Recherche Pour Le Developpement |
Huisman J.M.,Murdoch University |
And 6 more authors.
The Sargassum subgenera Bactrophycus and Arthrophycus were considered to be geographically restricted to the northern and southern hemispheres, respectively. Phylogenetic analyses of 19 Sargassum subgenus Bactrophycus species and eight Sargassum subgenus Arthrophycus species, based on a concatenated dataset of the loci ITS-2, cox3 and the rbcL-S spacer, showed that they formed a single clade, with Arthrophycus species nested within Bactrophycus section Halochloa.We merged the two subgenera as subgenus Bactrophycus and transferred ''Arthrophycus'' species to Sargassum section Halochloa. The genus now includes only the two subgenera, Sargassum and Bactrophycus, and both were found at temperate and subtropical latitudes; only subgenus Sargassum occurred at low latitudes near the equator, whereas subgenus Bactrophycus had an antitropical, disjunct distribution. © 2014 International Phycological Society. Source
Baylis A.M.M.,Deakin University |
Page B.,South Australian Research And Development Institute |
Page B.,Plant Biodiversity Center |
Staniland I.,British Antarctic Survey |
And 2 more authors.
Marine Mammal Science
The need to manage otariid populations has necessitated the development of a wide range of capture methods. Chemical restraint by remote drug delivery (i.e., darting) is a highly selective method that can be used to facilitate otariid capture in a range of scenarios, when other methods may be impracticable. However, the risks associated with darting otariids are not widely known and guidelines necessary to promote and refine best practice do not exist. We review the risks associated with darting and in light of our findings, develop darting guidelines to help practitioners assess and minimize risks during capture, anesthesia and recovery. Published studies reveal that mortalities associated with darting predominantly result from complications during anesthetic maintenance (e.g., prolonged respiratory depression, apnea, or hyperthermia), rather than from complications during capture or recovery. In addition to monitoring vital signs and proper intervention, the risk of irreversible complications during anesthesia can be reduced by administering drug doses that are sufficient to enable the capture and masking of animals, after which anesthetic depth can be regulated using gas anesthesia. © 2014 Society for Marine Mammalogy. Source