970 resultados para rapid identification


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study aimed to determine if pathotypic diversity of the sorghum rust pathogen, P. purpurea, exists in eastern Australia. A differential set of 10 Sorghum bicolor genotypes was used to identify four putative pathotypes from the 28 P. purpurea isolates that were tested. Pathotypes 1 and 3 were the most common, together comprising 85.7 % of the isolates tested, while pathotype 2 comprised 10.7 % of isolates, and pathotype 4 the remainder. Based on the limited number of isolates that were tested, there was evidence of geographic specialization amongst the pathotypes, with pathotype 1 not being found in north Queensland. This work has provided conclusive evidence that pathotypes of P. purpurea exist in the sorghum growing regions of Australia and has resulted in the development of a protocol for identifying pathotypes and screening breeding and experimental lines for resistance to these pathotypes. However, further investigations on the pathotypic diversity of P. purpurea and on the temporal and geographic distribution of these four as well as any additional undiscovered pathotypes are needed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Interactive identification keys for Australian smut fungi (Ustilaginomycotina and Pucciniomycotina, Microbotryales) and rust fungi (Pucciniomycotina, Pucciniales) are available online at http://collections.daff.qld.gov.au. The keys were built using Lucid software, and facilitate the identification of all known Australian smut fungi (317 species in 37 genera) and 100 rust fungi (from approximately 360 species in 37 genera). The smut and rust keys are illustrated with over 1,600 and 570 images respectively. The keys are designed to assist a wide range of end-users including mycologists, plant health diagnosticians, biosecurity scientists, plant pathologists, and university students. The keys are dynamic and will be regularly updated to include taxonomic changes and incorporate new detections, taxa, distributions and images. Researchers working with Australian smut and rust fungi are encouraged to participate in the on-going development and improvement of these keys.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The cossid moth (Coryphodema tristis) has a broad range of native tree hosts in South Africa. The moth recently moved into non-native Eucalyptus plantations in South Africa, on which it now causes significant damage. Here we investigate the chemicals involved in pheromone communication between the sexes of this moth in order to better understand its ecology, and with a view to potentially develop management tools for it. In particular, we characterize female gland extracts and headspace samples through coupled gas chromatography electro-antennographic detection (GC-EAD) and two dimensional gas chromatography mass spectrometry (GCxGC-MS). Tentative identities of the potential pheromone compounds were confirmed by comparing both retention time and mass spectra with authentic standards. Two electrophysiologically active pheromone compounds, tetradecyl acetate (14:OAc) and Z9-tetradecenyl acetate (Z9-14:OAc) were identified from pheromone gland extracts, and an additional compound (Z9-14:OH) from headspace samples. We further determined dose response curves for the identified compounds and six other structurally similar compounds that are common to the order Cossidae. Male antennae showed superior sensitivity toward Z9-14:OAc, Z7-tetradecenyl acetate (Z7-14:OAc), E9-tetradecenyl acetate (E9-14:OAc), Z9-tetradecenol (Z9-14:OH) and Z9-tetradecenal (Z9-14:Ald) when compared to female antennae. While we could show electrophysiological responses to single pheromone compounds, behavioral attraction of males was dependent on the synergistic effect of at least two of these compounds. Signal specificity is shown to be gained through pheromone blends. A field trial showed that a significant number of males were caught only in traps baited with a combination of Z9-14:OAc (circa 95 of the ratio) and Z9-14:OH. Addition of 14:OAc to this mixture also improved the number of males caught, although not significantly. This study represents a major step towards developing a useful attractant to be used in management tools for C. tristis and contributes to the understanding of chemical communication and biology of this group of insects.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Key message The potential for exploiting heterosis for sorghum hybrid production in Ethiopia with improved local adaptation and farmers preferences has been investigated and populations suitable for initial hybrid development have been identified. Abstract Hybrids in sorghum have demonstrated increased productivity and stability of performance in the developed world. In Ethiopia, the uptake of hybrid sorghum has been limited to date, primarily due to poor adaptation and absence of farmer’s preferred traits in existing hybrids. This study aimed to identify complementary parental pools to develop locally adapted hybrids, through an analysis of whole genome variability of 184 locally adapted genotypes and introduced hybrid parents (R and B). Genetic variability was assessed using genetic distance, model-based STRUCTURE analysis and pair-wise comparison of groups. We observed a high degree of genetic similarity between the Ethiopian improved inbred genotypes and a subset of landraces adapted to lowland agro-ecology with the introduced R lines. This coupled with the genetic differentiation from existing B lines, indicated that these locally adapted genotype groups are expected to have similar patterns of heterotic expression as observed between introduced R and B line pools. Additionally, the hybrids derived from these locally adapted genotypes will have the benefit of containing farmers preferred traits. The groups most divergent from introduced B lines were the Ethiopian landraces adapted to highland and intermediate agro-ecologies and a subset of lowland-adapted genotypes, indicating the potential for increased heterotic response of their hybrids. However, these groups were also differentiated from the R lines, and hence are different from the existing complementary heterotic pools. This suggests that although these groups could provide highly divergent parental pools, further research is required to investigate the extent of heterosis and their hybrid performance.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVES: 1. To determine whether incomplete rigor mortis resolution and 'cold shock' play a role in development of tough fish syndrome (TFS) in tropical Saddletail snapper. 2. To identify links between TFS and specific physiological factors in tropical Saddletail snapper. 3. Communicate findings and recommendations to stakeholders and assist with implementation of any changes to fishing or handling practices required.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Speeding is a major contributor to road injuries and fatalities and remains prevalent. Changing community perceptions about speeding is an important priority. Austroads commissioned research to identify a range of potential interventions for future trial and evaluation aimed at creating, increasing, and/or sustaining public demand for safer speeds. This project had three phases: a literature review; consultations with key stakeholders regarding intervention options (including feasibility, and likely benefits and costs of identified interventions); and providing research results, including recommendations for future phases of the program of work. The literature review led to the development of a draft Campaign Strategy targeting nine aims across three themes underpinning this research: 1) creating, 2) increasing, and 3) sustaining public demand for safer speeds on the road. Twenty-one stakeholders commented on the suitability and feasibility of, and likely barriers to, countermeasures within the draft Campaign Strategy and its applicability to the Australian and New Zealand context. There was overwhelming positive support for the proposed Campaign Strategy by the majority of respondents; many, noting that it addressed key misperceptions and complemented many existing approaches. A small number of respondents expressed some concerns with various aspects. Stakeholder feedback was incorporated into the final proposed Campaign Strategy to enhance its potential effectiveness. Wide diversity across jurisdictions makes the recommendation of individual interventions for specific areas problematic. Individual jurisdictions should consider a range of costs and benefits of the proposed Campaign Strategy to determine the likely feasibility from their unique perspective. Issues to be addressed when considering implementation of the proposed Campaign Strategy include speed limit setting policies, resourcing, messaging and advertising strategies, and political will associated with promoting safer speeds.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The specific activity of glutamine synthetase (L-glutamate: ammonia ligase, EC 6.3.1.2) in surface grown Aspergillus niger was increased 3-5 fold when grown on L-glutamate or potassium nitrate, compared to the activity obtained on ammonium chloride. The levels of glutamine synthetase was regulated by the availability of nitrogen source like NH4 + , and further, the enzyme is repressed by increasing concentrations of NH4 +. In contrast to other micro-organisms, the Aspergillus niger enzyme was neither specifically inactivated by NH4+ or L-glutamine nor regulated by covalent modification.Glutamine synthetase from Aspergillus niger was purified to homogenity. The native enzyme is octameric with a molecular weight of 385,000±25,000. The enzyme also catalyses Mn2+ or Mg2+-dependent synthetase and Mn2+-dependent transferase activity.Aspergillus niger glutamine synthetase was completely inactivated by two mol of phenylglyoxal and one mol of N-ethylmaleimide with second order rate constants of 3·8 M–1 min–1 and 760 M–1 min–1 respectively. Ligands like Mg. ATP, Mg. ADP, Mg. AMP, L-glutamate NH4+, Mn2+ protected the enzyme against inactivation. The pattern of inactivation and protection afforded by different ligands against N-ethylamaleimide and phenylglyoxal was remarkably similar. These results suggest that metal ATP complex acts as a substrate and interacts with an arginine ressidue at the active site. Further, the metal ion and the free nucleotide probably interact at other sites on the enzyme affecting the catalytic activity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The tomato I-3 and I-7 genes confer resistance to Fusarium oxysporum f. sp. lycopersici (Fol) race 3 and were introgressed into the cultivated tomato, Solanum lycopersicum, from the wild relative Solanum pennellii. I-3 has been identified previously on chromosome 7 and encodes an S-receptor-like kinase, but little is known about I-7. Molecular markers have been developed for the marker-assisted breeding of I-3, but none are available for I-7. We used an RNA-seq and single nucleotide polymorphism (SNP) analysis approach to map I-7 to a small introgression of S. pennellii DNA (c. 210 kb) on chromosome 8, and identified I-7 as a gene encoding a leucine-rich repeat receptor-like protein (LRR-RLP), thereby expanding the repertoire of resistance protein classes conferring resistance to Fol. Using an eds1 mutant of tomato, we showed that I-7, like many other LRR-RLPs conferring pathogen resistance in tomato, is EDS1 (Enhanced Disease Susceptibility 1) dependent. Using transgenic tomato plants carrying only the I-7 gene for Fol resistance, we found that I-7 also confers resistance to Fol races 1 and 2. Given that Fol race 1 carries Avr1, resistance to Fol race 1 indicates that I-7-mediated resistance, unlike I-2- or I-3-mediated resistance, is not suppressed by Avr1. This suggests that Avr1 is not a general suppressor of Fol resistance in tomato, leading us to hypothesize that Avr1 may be acting against an EDS1-independent pathway for resistance activation. The identification of I-7 has allowed us to develop molecular markers for marker-assisted breeding of both genes currently known to confer Fol race 3 resistance (I-3 and I-7). Given that I-7-mediated resistance is not suppressed by Avr1, I-7 may be a useful addition to I-3 in the tomato breeder's toolbox.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The performance of optoelectronic devices critically depends on the quality of active layer. An effective way to obtain a high quality layers is by creating excess of metal atoms through various heat treatments. Recently, rapid thermal annealing (RTA) has proved a versatile technique for the post-treatment of semiconductor materials as compared to other techniques due to its precise control over the resources. Thus, we carried out a set of experiments on SnS films to explore the influence of RTA treatment on their properties. From these experiments we noticed that the films treated at 400 °C for 1 min in N2 atmosphere have a low electrical resistivity of ~5 Ωcm with relatively high Hall mobility and carrier density of 99 cm2/Vs and 1.3 × 1016 cm−3, respectively. The observed results, therefore, emphasise that it is possible to obtain good quality SnS films through RTA treatment without disturbing their crystal structure.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conservation and sustainable productivity are vital issues for Australia. In order to manage vegetation well from an agricultural, recreational or conservation point of view, an understanding of individual plant species is important. Plants of Central Queensland provides a guide for identifying and understanding the plants of the region so that pastoralists and others can be better equipped to manage the vegetation resource of our grazing lands. Central Queensland straddles the Tropic of Capricorn, although many of the plants in the book will also be found outside this area, as shown by their distribution maps. The book provides information on the habit, distribution, foliage and fruits of 525 plant species. Informative notes highlighting declared, poisonous, weed and medicinal plants are included, and plants useful for bees and bush tucker are also noted. These are the most important plants you might see if you live in or travel through central Queensland. This book has an easy-to-read, non-botanical format, with helpful photographs and distribution maps that greatly aid anyone interested in the vegetation of central Queensland. It is based on a previous work of the same title but is greatly expanded, incorporating information on an additional 285 plant species.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Developing major infrastructure and construction (MIC) projects is complicated, since it involves multifaceted policy issues. As a result, appropriate participatory mechanisms have been increasingly employed to improve the legitimacy of the project decision process. Yet it cannot always guarantee a mutually acceptable solution since the expectations and requirements of multiple stakeholders involved can be diverse and even conflicting. Overcoming this necessitates a thorough identification and careful analysis of the expectations of various stakeholder groups in MIC projects. On the other hand, though most project stakeholder concerns are consistent across the globe, contextual differences may lead to diverse priority levels being attached to these factors. This research, therefore, aimed to examine the perceptual differences between paired stakeholder groups from mainland China mega-cities and Hong Kong in rating their concerns over MIC projects. The research findings are expected to benefit both the Central Government of China and the Government of Hong Kong SAR for coping better with the rapid expansion of MIC projects in the territory and the increasing expectations of social equality, and therefore achieving the much desired harmonious development of the community.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis presents a highly sensitive genome wide search method for recessive mutations. The method is suitable for distantly related samples that are divided into phenotype positives and negatives. High throughput genotype arrays are used to identify and compare homozygous regions between the cohorts. The method is demonstrated by comparing colorectal cancer patients against unaffected references. The objective is to find homozygous regions and alleles that are more common in cancer patients. We have designed and implemented software tools to automate the data analysis from genotypes to lists of candidate genes and to their properties. The programs have been designed in respect to a pipeline architecture that allows their integration to other programs such as biological databases and copy number analysis tools. The integration of the tools is crucial as the genome wide analysis of the cohort differences produces many candidate regions not related to the studied phenotype. CohortComparator is a genotype comparison tool that detects homozygous regions and compares their loci and allele constitutions between two sets of samples. The data is visualised in chromosome specific graphs illustrating the homozygous regions and alleles of each sample. The genomic regions that may harbour recessive mutations are emphasised with different colours and a scoring scheme is given for these regions. The detection of homozygous regions, cohort comparisons and result annotations are all subjected to presumptions many of which have been parameterized in our programs. The effect of these parameters and the suitable scope of the methods have been evaluated. Samples with different resolutions can be balanced with the genotype estimates of their haplotypes and they can be used within the same study.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Testing for mutagenicity and carcinogenicity has become an integral part of the toxicological evaluation of drugs and chemicals. Standard carcinogenicity tests in vivo require both large numbers of animals and prolonged experiments. To circumvent these problems, several rapid tests have been developed for preliminary screening of mutagens and carcinogens in vitro. Ames and his associates, the first to develop a mutation test, used mutant strains of Salmonella typhimurium [1]. Mutation tests with Escherichia coli, Bacillus subtilis, Neurospora crassa and Saccharomyces cerevisiae, and DNA-repair tests with E. coli and B. subtilis, have been developed. Cytogenetic assays, in vivo as well as in vitro, in both plant and animal systems, are also used to detect potential mutagens and carcinogens. Transfection is inhibited by base mutation, cleavage of DNA, loss of cohesive ends, interaction with histones, spermidine, nalidixic acid, etc. [3]. The efficiency of transfection is affected by temperature, DNA structure and the condition of the competence of the recipient cells [3]. Transfection assays with phages MS: RNA and ~i, x 174-DNA have been reported [15]. A fast and easy transfection assay using colitis bacteriophage DNA is reported in this communication.