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Assessment Strategies (assessment + strategy)
Selected AbstractsA meta-analysis of national research: Effects of teaching strategies on student achievement in science in the United StatesJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 10 2007Carolyn M. Schroeder This project consisted of a meta-analysis of U.S. research published from 1980 to 2004 on the effect of specific science teaching strategies on student achievement. The six phases of the project included study acquisition, study coding, determination of intercoder objectivity, establishing criteria for inclusion of studies, computation of effect sizes for statistical analysis, and conducting the analyses. Studies were required to have been carried out in the United States, been experimental or quasi-experimental, and must have included effect size or the statistics necessary to calculate effect size. Sixty-one studies met the criteria for inclusion in the meta-analysis. The following eight categories of teaching strategies were revealed during analysis of the studies (effect sizes in parentheses): Questioning Strategies (0.74); Manipulation Strategies (0.57); Enhanced Material Strategies (0.29); Assessment Strategies (0.51); Inquiry Strategies (0.65); Enhanced Context Strategies (1.48); Instructional Technology (IT) Strategies (0.48); and Collaborative Learning Strategies (0.95). All these effect sizes were judged to be significant. Regression analysis revealed that internal validity was influenced by Publication Type, Type of Study, and Test Type. External validity was not influenced by Publication Year, Grade Level, Test Content, or Treatment Categories. The major implication of this research is that we have generated empirical evidence supporting the effectiveness of alternative teaching strategies in science. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 44: 1436,1460, 2007 [source] Assessment Strategies for School-Based Mental Health CounselingJOURNAL OF SCHOOL HEALTH, Issue 9 2001Rachel Grier LCSW No abstract is available for this article. [source] Implementing life cycle assessment in product developmentENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 4 2003Gurbakhash Singh Bhander The overall aim of this paper is to provide an understanding of the environmental issues involved in the early stages of product development, and the capacity of Life Cycle Assessment (LCA) techniques to address these issues. The paper aims to outline the problems for the designer in evaluating the environmental benignity of a product from the outset, and to provide a framework for decision support based on the performance evaluation at different stages of the design process. The barriers that prevent product developers from using LCA are presented, as well as opportunities for introducing environmental criteria in the design process by meeting the designer's information requirements at the different life cycle stages. This can lead to an in-depth understanding of the attitudes of product developers towards the subject area, and an understanding of possible future directions for product development. This paper introduces an Environmentally Conscious Design method, and presents trade-offs between design degrees of freedom and environmental solutions. Life cycle design frameworks and strategies are also addressed. The paper collects experiences and ideas around the state-of-the-art in eco-design, from literature and personal experience, and provides eco-design life cycle assessment strategies. The end result of this presentation is to define the requirements for performance measurement techniques, and the environment needed to support life cycle evaluation throughout the evaluation of early stages of a product system. [source] Toxicity assessment and public policies: An urgent need for research,ENVIRONMENTAL TOXICOLOGY, Issue 5 2010Eric Vindimian Abstract The new European regulation on chemicals triggers a huge number of new testing. However, more than 2 years after the enforcement of this policy, toxicity assessment and risk assessment are still using single species tests that deliver little information. As it is often the case, the link between science and policy seems to be disrupted. However, policy makers need more than ever information on the fate and effects of chemicals on living systems. Without relevant knowledge for decision making, the application of the precautionary principle is the only reasonable way to manage risks. It is necessary to develop new risk assessment strategies using the last innovations from biology: the omics tools, ecology, ecosystem modeling, chemistry, and computing. This article highlights some of the recent trends in ecotoxicology and calls for a new research strategy. This strategy implies research to be funded by its users. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2010. [source] Exploring a taxonomy for aggression against women: can it aid conceptual clarity?AGGRESSIVE BEHAVIOR, Issue 6 2009Sarah Cook Abstract The assessment of aggression against women is demanding primarily because assessment strategies do not share a common language to describe reliably the wide range of forms of aggression women experience. The lack of a common language impairs efforts to describe these experiences, understand causes and consequences of aggression against women, and develop effective intervention and prevention efforts. This review accomplishes two goals. First, it applies a theoretically and empirically based taxonomy to behaviors assessed by existing measurement instruments. Second, it evaluates whether the taxonomy provides a common language for the field. Strengths of the taxonomy include its ability to describe and categorize all forms of aggression found in existing quantitative measures. The taxonomy also classifies numerous examples of aggression discussed in the literature but notably absent from quantitative measures. Although we use existing quantitative measures as a starting place to evaluate the taxonomy, its use is not limited to quantitative methods. Implications for theory, research, and practice are discussed. Aggr. Behav. 35:462,476, 2009. © 2009 Wiley-Liss, Inc. [source] Intellectual and adaptive behaviour functioning in pantothenate kinase-associated neurodegenerationJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 6 2007K. Freeman Abstract Background Pantothenate kinase-associated neurodegeneration (PKAN), an extremely rare autosomal recessive disorder resulting in iron accumulation in the brain, has a diverse phenotypic expression. Based on limited case studies of one or two patients, intellectual impairment is considered part of PKAN. Investigations of cognitive functioning have utilized specific neuropsychological tests, without attention to general intellectual skills or adaptive behaviour. Methods Sixteen individuals with PKAN completed measures of global intellectual functioning, and participants or care providers completed measures of adaptive behaviour skills and day-to-day functional limitations. Clinicians provided global ratings of condition severity. Results Testing with standardized measures documented varied phenotypic expression, with general cognitive skills and adaptive behaviour ranging from high average to well below average. Age of disease onset correlated with measures of intellectual functioning, adaptive functioning and disease severity. Conclusions Findings support previously described clinical impressions of varied cognitive impairment and the association between age of onset and impairment. Further, they add important information regarding the natural history of the disease and suggest assessment strategies for use in treatment trials. [source] Emotional intelligence: a vital prerequisite for recruitment in nursingJOURNAL OF NURSING MANAGEMENT, Issue 6 2001C. Cadman MED This paper explores Goleman's (1996) concept of ,emotional intelligence' in relation to recruitment to preregistration nurse education programmes. Current studies consistently demonstrate that emotional intelligence is the common factor which marks out individuals as leaders, innovators and effective managers. The role of the qualified nurse is evolving continually and ,portable' skills are the key qualities demanded by a health care system under pressure to compete. These include the ability to work effectively in teams, the ability to recognize and respond appropriately to one's own and others' feelings and the ability to motivate oneself and others. They are collectively termed ,emotional intelligence'. We believe we need selection processes that will determine levels of emotional intelligence in prospective candidates, as they could be a reliable predictor of success in both clinical nursing practice and academic study. Research indicates that emotional intelligence cannot be developed quickly enough through interpersonal skills training and therefore it is essential that nurse educators create assessment strategies that will identify emotional intelligence at recruitment. [source] "Too many theories and not enough instruction": perceptions of preservice teacher preparation for literacy teaching in Australian schoolsLITERACY, Issue 2 2006William Louden Abstract In this paper, we describe part of an Australian national research project that aimed to find out how well prepared beginning teachers are to teach literacy. A majority of beginning teachers participating in a series of national surveys and focus group meetings were confident about their personal literacy skills, their conceptual understandings of literacy, their understanding of curriculum documents and assessment strategies and their broad preparation to teach. Fewer beginning teachers were confident about their capacity to teach specific aspects of literacy such as viewing, spelling, grammar and phonics, or about their capacity to meet the challenges of student diversity. Senior staff working with beginning teachers were generally sceptical about the quality of teacher preparation for teaching literacy and were less confident than the beginning teachers about personal literacy skills. We discuss these findings in relation to the relative importance placed on particular substantive and structural issues by the study participants and in terms of previous findings. [source] Evaluation of a Non-Targeted "Omic" Approach in the Safety Assessment of Genetically Modified PlantsPLANT BIOLOGY, Issue 5 2006S. B. Metzdorff Abstract: Genetically modified plants must be approved before release in the European Union, and the approval is generally based upon a comparison of various characteristics between the transgenic plant and a conventional counterpart. As a case study, focusing on safety assessment of genetically modified plants, we here report the development and characterisation of six independently transformed Arabidopsis thaliana lines modified in the flavonoid biosynthesis. Analyses of integration events and comparative analysis for characterisation of the intended effects were performed by PCR, quantitative Real-time PCR, and High Performance Liquid Chromatography. Analysis by cDNA microarray was used as a non-targeted approach for the identification of potential unintended effects caused by the transformation. The results revealed that, although the transgenic lines possessed different types of integration events, no unintended effects were identified. However, we found that the majority of genes showing differential expression were identified as stress-related genes and that environmental conditions had a large impact on the expression of several genes, proteins, and metabolites. We suggest that the microarray approach has the potential to become a useful tool for screening of unintended effects, but state that it is crucial to have substantial information on the natural variation in traditional crops in order to be able to interpret "omics" data correctly within the framework of food safety assessment strategies of novel plant varieties, including genetically modified plant varieties. [source] IPOS Sutherland Memorial Lecture: psycho-oncology and health care researchPSYCHO-ONCOLOGY, Issue 6 2008Uwe KochArticle first published online: 2 MAY 200 Abstract Remarkable changes of health-care systems, increasing costs of health care and of social inequality in modern societies, an aging population and the increase of chronic illnesses such as cancer implicate various future challenges for the provision of health care. Health-care research aims to improve the effectiveness and efficiency of patient-oriented services involving the evaluation of innovative treatment approaches and settings. It deals with the patients' path through different areas of health-care systems in order to identify significant factors for the provision of quality assurance of structures and resources concerning treatments, processes and health outcomes. Health-care research focusses on three main topics that play an important role for quality management: (1) the admission to health-care services and assessment strategies including indication, utilization and specificity of settings and target groups; (2) the treatment process including the implementation, standardization and flexibility of services and dose-effect relationship of interventions; (3) health-care outcome including effectiveness and efficiency of interventions and services, the cost-benefit relationship and the transfer from research to health-care practice. Given the objectives of health-care research, the topics of health-care research in psychosocial care for cancer patients include the study of structural conditions of psycho-oncological services, the epidemiology of distress and mental disorders and the subjective need of psycho-oncological support in cancer patients, the improvement of psycho-oncological measures and assessment strategies in daily treatment, the study of psycho-oncological interventions under routine conditions, and quality assurance. Requirements of future health-care research and developments of psycho-oncology including aspects of orientation, strategies, health-care equity, and resources are discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] Biomarkers for detection of prenatal alcohol exposure: A critical review of fatty acid ethyl esters in meconium,,BIRTH DEFECTS RESEARCH, Issue 7 2008Larry Burd Abstract BACKGROUND: The objective of this study was a review of published studies utilizing measurement of fatty acid ethyl esters (FAEE) in meconium as biomarkers for prenatal alcohol exposure. METHODS: We completed a literature search of PubMed using the terms meconium, fatty acid ethyl esters, biomarkers, and prenatal alcohol exposure. We included only peer reviewed studies utilizing analysis of meconium for the presence of FAEE in humans through the year 2007. RESULTS: We found 10 articles reporting on original research examining the relationship of FAEE from meconium and prenatal alcohol exposure (PAE). The 10 articles used six different PAE assessment strategies and four different analytical techniques for determining FAEE endpoints. The articles included 2,221 subjects (range 4 to 725) with 455 (20.5%) subjects identified as exposed using the methods stated in the articles. FAEE levels above the studies' respective cutoffs were reported for 502 (22.6%) subjects. CONCLUSIONS: The accurate identification of alcohol-exposed pregnancies represents a significant challenge in the development of FAEE detection cutoffs to maximize the sensitivity and specificity of the test. We present several options for the improvement of exposure assessment in future studies of FAEE as biomarkers for PAE. Birth Defects Research (Part A), 2008. © 2008 Wiley-Liss, Inc. [source] Do we know when our clients get worse? an investigation of therapists' ability to detect negative client changeCLINICAL PSYCHOLOGY AND PSYCHOTHERAPY (AN INTERNATIONAL JOURNAL OF THEORY & PRACTICE), Issue 1 2010Derek Hatfield Abstract Routine clinical judgment is often relied upon to detect client deterioration. How reliable are therapists' judgments of deterioration? Two related studies were conducted to investigate therapist detection of client deterioration and therapist treatment decisions in situations of deterioration. The first study examined therapists' ability to detect client deterioration through the review of therapy progress notes. Therapist treatment decisions in cases of client deterioration were also explored. Therapists had considerable difficulty recognizing client deterioration, challenging the assumption that routine clinical judgment is sufficient when attempting to detect client deterioration. A second study was a survey of therapists asking how they detect client deterioration and what treatment decisions they make in response. Symptom worsening was the most commonly stated cue of deterioration. Copyright © 2009 John Wiley & Sons, Ltd. Key Practitioner Message: , Clinicians may have a difficult time detecting when their client's symptoms are worsening. , Outcome assessment strategies do exist to help clinicians detect client deterioration. [source] Applying developmental theory to the assessment and treatment of childhood disorders: does it make a difference?CLINICAL PSYCHOLOGY AND PSYCHOTHERAPY (AN INTERNATIONAL JOURNAL OF THEORY & PRACTICE), Issue 5 2001Thomas H. Ollendick In this paper, we examine the role of developmental theory in the assessment and treatment of child behaviour disorders, with special reference to the anxiety disorders. Following a brief review of the tenets of developmental psychology and developmental psychopathology, we illustrate the role of developmental theory in clinical research and practice. We suggest that developmental theory guides us in the selection and use of developmentally sensitive assessment strategies. Moreover, we indicate that use of developmental theory assists us in the treatment of children and adolescents by helping us determine when a behaviour problem is significant and when to initiate treatment, how to determine the goals of treatment and to select targets for treatment outcome, which treatment strategies to select for intervention, and how to determine the context of intervention. We conclude that the importance of developmental theory is axiomatic when working with children and adolescents. Still, considerable more work is needed before we can conclude that we have fully integrated developmental theory into our ongoing clinical research and practice with children. Copyright © 2001 John Wiley & Sons, Ltd. [source] Intra- and interlaboratory calibration of the DR CALUX® bioassay for the analysis of dioxins and dioxin-like chemicals in sedimentsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2004Harrie T. Besselink Abstract In the Fourth National Policy Document on Water Management in the Netherlands [1], it is defined that in 2003, in addition to the assessment of chemical substances, special guidelines for the assessment of dredged material should be recorded. The assessment of dredged material is based on integrated chemical and biological effect measurements. Among others, the DR CALUX® (dioxin responsive,chemically activated luciferase expression) bioassay has tentatively been recommended for inclusion in the dredged material assessment. To ensure the reliability of this bioassay, an intra- and interlaboratory validation study, or ring test, was performed, organized by the Dutch National Institute for Coastal and Marine Management (RIKZ) in cooperation with BioDetection Systems BV (BDS). The intralaboratory repeatability and reproducibility and the limit of detection (LOD) and quantification (LOQ) of the DR CALUX bioassay were determined by analyzing sediment extracts and dimethyl sulfoxide (DMSO) blanks. The highest observed repeatability was found to be 24.1%, whereas the highest observed reproducibility was calculated to be 19.9%. Based on the obtained results, the LOD and LOQ to be applied for the bioassay are 0.3 and 1.0 pM, respectively. The interlaboratory calibration study was divided into three phases, starting with analyzing pure chemicals. During the second phase, sediment extracts were analyzed, whereas in the third phase, whole sediments had to be extracted, cleaned, and analyzed. The average interlaboratory repeatability increased from 14.6% for the analysis of pure compound to 26.1% for the analysis of whole matrix. A similar increase in reproducibility with increasing complexity of handlings was observed with the interlaboratory reproducibility of 6.5% for pure compound and 27.9% for whole matrix. The results of this study are intended as a starting point for implementing the integrated chemical,biological assessment strategy and for systematic monitoring of dredged materials and related materials in the coming years. [source] Detection of Delirium by Bedside Nurses Using the Confusion Assessment MethodJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2006Joke Lemiengre RN A prospective, descriptive study was used to assess the diagnostic validity of the Confusion Assessment Method (CAM) administered at the bedside by nurses in daily practice. Two different scoring methods of the CAM (the specific (SPEC) and sensitive (SENS) methods) were compared with a criterion standard (CAM completed by trained research nurses). During a 5-month period, all patients consecutively admitted to an acute geriatric ward of the University Hospitals of Leuven (Belgium) were enrolled in the study. The 258 elderly inpatients who were included underwent 641 paired but independent ratings of delirium by bedside and trained research nurses. Delirium was identified in 36 of the 258 patients (14%) or in 42 of the 641 paired observations (6.5%). The SENS method of the CAM algorithm as administered by bedside nurses had the greatest diagnostic accuracy, with 66.7% sensitivity and 90.7% specificity; the SPEC method had 23.8% sensitivity and 97.7% specificity. Bedside nurses had difficulties recognizing the features of acute onset, fluctuation, and altered level of consciousness. For both scoring methods, bedside nurses had difficulties with the identification of elderly patients with delirium but succeeded in diagnosing correctly those patients without delirium in more than 90% of observations. Given these results, additional education about delirium with special attention to guided training of bedside nurses in the use of an assessment strategy such as the CAM for the recognition of delirium symptoms is warranted. [source] An assessment strategy for identifying legacy system evolution requirements in eBusiness contextJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 4-5 2004Lerina Aversano Abstract The enactment of e Business processes requires the effective usage of the existing legacy applications in the e Business initiatives. Technical issues are not enough to drive the evolution of the existing legacy applications, but problems concerning the perspectives, strategies, and business of the enterprises have to be considered. In particular, there is a strict relationship between the evolution of the legacy systems and the evolution of the e Business processes. This paper proposes a strategy to extract the requirements for a legacy system evolution from the requirements of the e Business evolution. The proposed strategy aims at characterizing the software system within the whole environment in which its evolution will be performed. It provides a useful set of attributes addressing technical, process, and organizational issues. Moreover, a set of assessment activities is proposed affecting the order in which the attributes are assessed. Copyright © 2004 John Wiley & Sons, Ltd. [source] Setting up a clinical skills learning facilityMEDICAL EDUCATION, Issue 2003P Bradley Objective, This paper outlines the considerations to be made when establishing a clinical skills learning facility. Considerations, Establishing a clinical skills learning facility is a complex project with many possible options to be considered. A number of professional groups, undergraduate or postgraduate, may be users. Their collaboration can have benefits for funding, uses and promotion of interprofessional education. Best evidence and educational theory should underpin teaching and learning. The physical environment should be flexible to allow a range of clinical settings to be simulated and to facilitate a range of teaching and learning methods, supported by computing and audio-visual resources. Facilities should be available to encourage self-directed learning. The skills programme should be designed to support the intended learning outcomes and be integrated within the overall curriculum, including within the assessment strategy. Teaching staff may be configured in a number of ways and may be drawn from a variety of backgrounds. Appropriate staff development will be required to ensure consistency and quality of teaching with monitoring and evaluation to assure appropriate standards. Patients can also play a role, not only as passive teaching material, but also as teachers and assessors. Clinical, diagnostic and therapeutic equipment will be required, as will models and manikins. The latter will vary from simple part task trainers to highly sophisticated human patient simulators. Care must be taken when choosing equipment to ensure it matches specified requirements for teaching and learning. Conclusion, Detailed planning is required across a number of domains when setting up a clinical skills learning facility. [source] Board development practices and competent board members: Implications for performanceNONPROFIT MANAGEMENT & LEADERSHIP, Issue 3 2007William A. Brown This study explores underlying assumptions about board development practices in nonprofit governance. Specifically, a model was developed to determine if using recommended recruitment, board member orientation, and evaluation practices resulted in more competent board members and if the presence of these board members led to better board performance. The sample consisted of 1,051 survey responses from CEOs and board chairs representing 713 credit unions. As member-benefit nonprofit organizations, credit unions rely almost exclusively on voluntary board members in an oversight capacity. Results support the contention that board development practices lead to more capable board members, and the presence of these board members tends to explain board performance. The study advances the understanding of nonprofit board development practices by further defining the concept and proposing an empirically tested assessment strategy. Furthermore, the findings support using specific recruitment practices that should strengthen nonprofit boards. [source] Pain Symptom Profiles in Persons with Spinal Cord InjuryPAIN MEDICINE, Issue 7 2009Yenisel Cruz-Almeida MSPH ABSTRACT Objective., Persistent pain is a common consequence of spinal cord injury. A patient-specific assessment that combines both the identification of pain symptoms and psychosocial factors is needed for a tailored treatment approach. The aim of the study was to define pain symptom profiles and to determine their relationship with psychosocial factors in persons with spinal cord injury. Design., Face-to-face interview and examination. Setting., VA Medical Center and Miami Project to Cure Paralysis, Miami, Florida. Patients., Persons with spinal cord injury (135 men and 21 women) provided detailed descriptions of 330 neuropathic pains. Outcome Measures., The American Spinal Injury Impairment Scale, pain history and measures of pain interference, life satisfaction, locus of control, social support and depression. Results., The exploratory factor analyses and regression analyses revealed three distinct symptom profiles: 1) aching, throbbing pain, aggravated by cold weather and constipation predicted by a combination of chance locus of control and lower levels of life satisfaction; 2) stabbing, penetrating, and constant pain of high intensity predicted by a combination of pain interference, localized pain, powerful others locus of control and depressed mood; and 3) burning, electric, and stinging pain aggravated by touch and muscle spasms predicted by pain interference. Conclusions., Although these results need to be replicated in other spinal cord injury samples, our findings suggest that pain symptom profiles may be a useful way to further characterize pain in a comprehensive assessment strategy. [source] Peaks and troughs,an exploration of patient perspectives of dangerous and severe personality disorder assessment (Peaks Unit, Rampton Hospital)PERSONALITY AND MENTAL HEALTH, Issue 1 2008Lisa Maltman Rationale,Although accessing user-perspectives is a key National Health Service initiative, the literature reporting user's views of forensic services, particularly dangerous and severe personality disorder (DSPD) services, is in its infancy. Aim and Design,This qualitative study applied thematic analysis to 12 semi-structured interviews aimed to enhance professional understanding of how Peaks Unit treatment-ward participants retrospectively perceive their experience of being admitted and assessed at the unit. Findings,Reported themes include ,fear' associated with participants' personal safety concerns and apprehensions regarding inhumane treatment and prolonged detention. The local metaphor of the DSPD Unit as the ,dark side' exacerbated such fears. ,Shock' also emerged as a primary theme resulting from unexpected admissions, security measures and some staff responses. ,Offering hope' provided a further theme with many participants reporting a climate of therapeutic optimism within staff teams and ,refreshing' opportunities for change. Reservations were also expressed about the service potentially offering ,false hope'. Several suggestions are proposed for future assessment strategy including escalating user-involvement activity, managing expectations, promoting therapeutic optimism and helping patients to attain a realistic sense of hope in order to maximise therapeutic engagement. Copyright © 2008 John Wiley & Sons, Ltd. [source] Dynamics of affective experience and behavior in depressed adolescentsTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 11 2009Lisa B. Sheeber Background:, Depression is often characterized as a disorder of affect regulation. However, research focused on delineating the key dimensions of affective experience (other than valence) that are abnormal in depressive disorder has been scarce, especially in child and adolescent samples. As definitions of affect regulation center around processes involved in initiating, maintaining, and modulating the occurrence, intensity, and duration of affective experiences, it is important to examine the extent to which affective experiences of depressed youth differ on these dimensions from those of healthy youth. Methods:, The affective behavior and experience of adolescents with major depressive disorder (MDD; n = 75) were compared to a demographically matched cohort of healthy adolescents (n = 77). Both samples were recruited from community high schools. A multi-source (parents and adolescent), multi-method (interviews, behavioral observations, questionnaires) assessment strategy was used to examine positive and negative affects. Results:, Depressed youth had significantly longer durations, higher frequency, and greater intensity when experiencing angry and dysphoric affects and shorter durations and less frequency of happy affect when compared to healthy youth. The most consistent, cross-method results were evident for duration of affect. Conclusions:, Clinically depressed adolescents experienced disturbances in affective functioning that were evident in the occurrence, intensity, and duration of affect. Notably, the disturbances were apparent in both positive and negative affects. [source] Do virus-resistant plants pose a threat to non-target ecosystems?AUSTRAL ECOLOGY, Issue 5 2009Abstract One key environmental risk associated with the release of novel disease-resistant plants is the potential for non-target host populations to acquire resistance genes and undergo enemy release, leading to damage to associated native plant populations in high conservation-value ecosystems. Unfortunately, the dynamics of most natural pathosystems are poorly understood, and risk assessment of disease-resistant plants remains a challenge. Here we describe the first stage of a multi-tiered risk assessment strategy aimed at quantifying potential ecological release in a model pathosystem (the weedy pasture species Trifolium repens infected with Clover yellow vein virus; ClYVV) in order to assess the level of risk posed by genetically modified and conventionally bred disease-resistant host genotypes to non-target plant communities in south-eastern Australia. Glasshouse inoculation and growth experiments using 14 ClYVV isolates and 20 wild T. repens lines collected from high conservation-value montane grassland and woodland communities show that viral infection reduces the survival and growth of host plants by on average 10,50%. However, T. repens lines exhibited variable levels of resistance and tolerance to virus infection and ClYVV isolates differed in infectivity and aggressiveness, with grassland isolates having a greater pathogenic effect on associated host plants than woodland isolates. We conclude that ClYVV potentially plays an important role in limiting the size of T. repens populations in some at-risk non-target ecosystems and that second-tier field experiments are required to adequately quantify the risk associated with the commercial release of V-R T. repens genotypes in Australia. [source] | ||||||||||||||||||||||