985 resultados para fish diversity


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‘Demonstration reaches’ are sections of river where multiple threats to native fish are addressed through river rehabilitation and strong community participation. They are an important way of promoting the key driving actions of the Murray-Darling Basin Authority's Native Fish Strategy (NFS) by using on-ground community-driven rehabilitation. Measuring rehabilitation success against well-defined targets and using this information to adaptively mange activities is fundamental to the demonstration reach philosophy. Seven years on from the establishment of the first demonstration reach, there are now seven throughout the Murray-Darling Basin (MDB), all in differing states of maturation and but all applying a standardised framework for monitoring native fish outcomes. In this study, we reflect on the role that demonstration reaches have played within the NFS, synthesise some key findings from 32 monitoring and evaluation outputs, and highlight some of the successes and barriers to success. We make recommendations as to how to strengthen the demonstration reach model to ensure it remains a relevant approach for fish habitat rehabilitation beyond the NFS and MDB.

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Members of the family Circoviridae, specifically the genus Circovirus, were thought to infect only vertebrates; however, members of a sister group under the same family, the proposed genusCyclovirus, have been detected recently in insects. In an effort to explore the diversity of cycloviruses and better understand the evolution of these novel ssDNA viruses, here we present five cycloviruses isolated from three dragonfly species (Orthetrum sabina, Xanthocnemis zealandica and Rhionaeschna multicolor) collected in Australia, New Zealand and the USA, respectively. The genomes of these five viruses share similar genome structure to other cycloviruses, with a circular ~1.7 kb genome and two major bidirectionally transcribed ORFs. The genomic sequence data gathered during this study were combined with all cyclovirus genomes available in public databases to identify conserved motifs and regulatory elements in the intergenic regions, as well as determine diversity and recombinant regions within their genomes. The genomes reported here represent four different cyclovirus species, three of which are novel. Our results confirm that cycloviruses circulate widely in winged-insect populations; in eight different cyclovirus species identified in dragonflies to date, some of these exhibit a broad geographical distribution. Recombination analysis revealed both intra-and inter-species recombination events amongst cycloviruses, including genomes recovered from disparate sources (e.g. goat meat and human faeces). Similar to other well-characterized circular ssDNA viruses, recombination may play an important role in cyclovirus evolution. © 2013 SGM.

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Using mitochondrial DNA for species identification and population studies assumes that the genome is maternally inherited, circular, located in the cytoplasm and lacks recombination. This study explores the mitochondrial genomes of three anomalous mackerel. Complete mitochondrial genome sequencing plus nuclear microsatellite genotyping of these fish identified them as Scomberomorus munroi (spotted mackerel). Unlike normal S. munroi, these three fish also contained different linear, mitochondrial genomes of Scomberomorus semifasciatus (grey mackerel). The results are best explained by hybridisation, paternal leakage and mitochondrial DNA linearization. This unusual observation may provide an explanation for mtDNA outliers in animal population studies. © 2013.

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We tested the effect of near-future CO2 levels (a parts per thousand 490, 570, 700, and 960 mu atm CO2) on the olfactory responses and activity levels of juvenile coral trout, Plectropomus leopardus, a piscivorous reef fish that is also one of the most important fisheries species on the Great Barrier Reef, Australia. Juvenile coral trout reared for 4 weeks at 570 mu atm CO2 exhibited similar sensory responses and behaviors to juveniles reared at 490 mu atm CO2 (control). In contrast, juveniles reared at 700 and 960 mu atm CO2 exhibited dramatically altered sensory function and behaviors. At these higher CO2 concentrations, juveniles became attracted to the odor of potential predators, as has been observed in other reef fishes. They were more active, spent less time in shelter, ventured further from shelter, and were bolder than fish reared at 490 or 570 mu atm CO2. These results demonstrate that behavioral impairment of coral trout is unlikely if pCO(2) remains below 600 mu atm; however, at higher levels, there are significant impacts on juvenile performance that are likely to affect survival and energy budgets, with consequences for predator-prey interactions and commercial fisheries.

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This is the first report of the genetic diversity within ilarvirus subgroup 1 from eastern Australia. It supports the separation of tobacco streak virus (TSV) strains from parthenium (Parthenium hysterophorus) and crownbeard (Verbescina encelioides) based on serology and host specificity. It has confirmed one previously described strain of TSV as a member of the species Strawberry necrotic shock virus and another as a new subgroup 1 ilarvirus, ageratum latent virus (AgLV), from Ageratum houstonianum. A multiplex RT-PCR showed that the genetically distinct strains of TSV and AgLV were commonly found in symptomless infections in virus-specific alternative weed hosts growing over a wide geographical range in eastern Australia. TSV has been one of the most damaging viruses in Australian oilseed and pulse crops in recent years, and this study has provided the taxonomic knowledge essential for the development of control programs for these viruses. © 2013 Springer-Verlag Wien.

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An economic survey of the commercial operators currently active in the Queensland Coral Reef Fin-Fish Fishery has been carried out, as part of a research project aimed at evaluating alternative management options for this fishery. This paper presents the background analysis used as a basis to develop the sampling design for this survey. The background analysis focuses on activity patterns of the fleet based on effort and catch information, as well as patterns of quota ownership. Based on this information, a fishing business profile describing the micro-economic structure of fishing operations is developed. This profile, in conjunction with the qualitative information gained in undertaking the economic surveys, allows preliminary understanding of the key drivers of profitability in the CRFFF, and possible impacts of external factors on fishing operations.

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Assessment of genetic diversity is an essential component in germplasm characterisation and utilisation. In this study the genetic diversity of mango was determined among 254 Mangifera indica L. accessions and related Mangifera species originating from 12 diverse geographic areas using eleven known simple sequence repeat (SSR) markers from mango. A total of 133 alleles were detected, ranging from eight (LMMA12) to 16 (MIAC-5) alleles per locus with a mean value of 12.36 and an average polymorphism information content (PLC) of 0.72. The mean number of alleles (8.45) was highest in the South East Asian accessions (Indonesia/Malesia) and lowest in the accessions from the Philippines (2.55). Diversity analysis divided the accessions into four major nodes broadly representing their geographical origins. The genetic diversity of 'Kensington Pride' was confirmed as being very low and no parents for this cultivar were identified. No association could be established between SSR markers analysed and embryony. Ten synonymous accessions were identified with matching genetic identity with at least one other accession at all SSR loci examined. Twenty-two unique genotypes were identified for 50 trees previously assigned different accession names. The remaining accessions were genetically distinct from each other. This increased understanding of genetic diversity in the Australian National Mango Genebank will assist breeders to better select parents with the potential to contribute desired genes to the progeny and thus more rapidly deliver improved cultivars to industry to meet consumer demand. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.

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Ambrosia beetle fungiculture represents one of the most ecologically and evolutionarily successful symbioses, as evidenced by the 11 independent origins and 3500 species of ambrosia beetles. Here we document the evolution of a clade within Fusarium associated with ambrosia beetles in the genus Euwallacea (Coleoptera: Scolytinae). Ambrosia Fusarium Clade (AFC) symbionts are unusual in that some are plant pathogens that cause significant damage in naive natural and cultivated ecosystems, and currently threaten avocado production in the United States, Israel and Australia. Most AFC fusaria produce unusual clavate macroconidia that serve as a putative food source for their insect mutualists. AFC symbionts were abundant in the heads of four Euwallacea spp., which suggests that they are transported within and from the natal gallery in mandibular mycangia. In a four-locus phylogenetic analysis, the AFC was resolved in a strongly supported monophyletic group within the previously described Cade 3 of the Fusarium solani species complex (FSSC). Divergence-time estimates place the origin of the AFC in the early Miocene similar to 21.2 Mya, which coincides with the hypothesized adaptive radiation of the Xyleborini. Two strongly supported clades within the AFC (Clades A and B) were identified that include nine species lineages associated with ambrosia beetles, eight with Euwallacea spp. and one reportedly with Xyleborus ferrugineus, and two lineages with no known beetle association. More derived lineages within the AFC showed fixation of the clavate (club-shaped) macroconidial trait, while basal lineages showed a mix of clavate and more typical fusiform macroconidia. AFC lineages consisted mostly of genetically identical individuals associated with specific insect hosts in defined geographic locations, with at least three interspecific hybridization events inferred based on discordant placement in individual gene genealogies and detection of recombinant loci. Overall, these data are consistent with a strong evolutionary trend toward obligate symbiosis coupled with secondary contact and interspecific hybridization. (C) 2013 Elsevier Inc. All rights reserved.

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INTRODUCTION AND BACKGROUND: This presentation draws on a body of work assessing cultural safety's potential to generate change in mental health nursing research (Cox and Simpson 2015), in education and in clinical practice (Cox and Taua 2013, 2016; Happell, Cowin, Roper, Lakeman & Cox 2013). It presents evidence to suggest that cultural safety could resolve the conceptual confusion surrounding culture and diversity in nursing curricular, in clinical and in research practice. The history and nature of mental health work recommend cultural safety to focus attention on diversity, power imbalance, racism, cultural dominance, and structural inequality, identified as barriers and tensions in clinical practice and in service user participation. Cultural safety gives mental health nursing a well theorized and articulated model, which is evolving to improve practice into the future. DESCRIPTION: This work involved an immersion in the literature on cultural safety and the Service User Research movement. It draws on 5 months' work with a service users' research group in the UK and reflections on 9 years of cultural safety teaching. POLICY/PRACTICE CHANGE: This work provokes a crucial change of emphasis from locating the source of issues in the diversity of people to locating it in how society responds to diversity: a change from individualistic to systemic concerns. IMPLICATIONS FOR MENTAL HEALTH NURSING: Cultural safety in clinical practice, education, and research is specifically concerned with awareness of the impact of systemic workplace cultures and with staff cultural self-awareness to bring about cultural change and person-centred care of individuals' unique needs and aspirations within their life context.

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In Sudan Chickpea chlorotic dwarf virus (CpCDV, genus Mastrevirus, family Geminiviridae) is an important pathogen of pulses that are grown both for local consumption, and for export. Although a few studies have characterised CpCDV genomes from countries in the Middle East, Africa and the Indian subcontinent, little is known about CpCDV diversity in any of the major chickpea production areas in these regions. Here we analyse the diversity of 146 CpCDV isolates characterised from pulses collected across the chickpea growing regions of Sudan. Although we find that seven of the twelve known CpCDV strains are present within the country, strain CpCDV-H alone accounted for ∼73% of the infections analysed. Additionally we identified four new strains (CpCDV-M, -N, -O and -P) and show that recombination has played a significant role in the diversification of CpCDV, at least in this region. Accounting for observed recombination events, we use the large amounts of data generated here to compare patterns of natural selection within protein coding regions of CpCDV and other dicot-infecting mastrevirus species.