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1.
J Glob Health ; 13: 06035, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37655370

ABSTRACT

Background: While much research has addressed mental health concerns related to the coronavirus disease 2019 (COVID-19) pandemic, there remains a scarcity of studies specifically exploring the changes in anxiety and depression among university students before and after the implementation of COVID-19 mitigation measures. Methods: In this systematic review and meta-analysis, we searched databases including MEDLINE (Ovid), EMBASE (Ovid), PsycINFO (Ovid), CINAHL (EBSCO), ERIC (EBSCO), the WHO COVID-19 database, Scopus, and Science Citation Index (Web of Science) as of 15 February 2023. We included studies that used a validated tool to measure changes in anxiety or depression at two distinct time points - before (T1) and during (T2); during (T2) and after (T3); or before (T1) and after (T3) COVID-19 mitigation. The quality of studies was assessed using an adapted Joanna Briggs Institute Checklist for longitudinal studies. Utilising random-effects models, we synthesised changes in continuous outcomes as standardised mean difference (SMD) with 95% confidence interval (CI) and binary outcomes as risk difference (RD) with 95% CI. Results: In total, 15 studies were included in this review, with eight of moderate and seven of high quality. In most of the included studies (n = 13), the majority of participants were women. Eleven studies analysed mental health outcomes between T1 and T2 of COVID-19 mitigations. Continuous symptom changes were a minimal or small improvement for anxiety (SMD = -0.03, 95% CI = -0.24 to 0.19, I2 = 90%); but worsened for depression (SMD = 0.26, 95% CI = -0.01 to 0.62). However, the proportions of students reporting moderate-to-severe symptoms, defined by specific cut-offs, increased during COVID-19 mitigation measures for both anxiety (RD = 0.17, 95% CI = -0.04 to 0.38, I2 = 95%) and depression (RD = 0.12, 95% CI = 0.03 to 0.22, I2 = 72%). Sensitivity analyses, which distinguished between baseline periods based on awareness of COVID-19, demonstrated an exacerbation of both symptoms when comparing the period before the global awareness of the COVID-19 outbreak (before December 2019) with the period during the implementation of mitigation measures. Conclusions: Mental health outcomes, especially depressive symptoms, were observed to worsen in university students during COVID-19 mitigations. Despite considerable heterogeneity requiring careful interpretation of results, the impact of COVID-19 mitigations on mental health in university students is evident. Registration: PROSPERO (CRD42021266889).


Subject(s)
COVID-19 , Depression , Female , Humans , Male , Depression/epidemiology , Universities , COVID-19/epidemiology , Anxiety/epidemiology , Databases, Factual
2.
J Glob Health ; 13: 04011, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36655877

ABSTRACT

Background: Childhood and adolescence are critical stages for a healthy life. To support countries in promoting health and development and improving health care for this age group, the WHO Regional Office for Europe developed the European strategy for child and adolescent health 2015-2020, which was adopted by all countries. This paper reports progress in the strategy's implementation until 2020. Methods: A survey was sent to all ministries of health of the 53 Member States of the WHO European Region. Responses were received from 45 Member States. Results are presented in this paper. Results: The European Region made overall progress in recent years, but increasing levels of overweight and obesity among children, adolescent mental health and low breastfeeding rates are recognized as key national challenges. Although forty-one countries adopted a national child and adolescent health strategy, only eight countries involve children in their review, development and implementation stages. Two-thirds of countries have a strategy for health-promoting schools and a school curriculum for health education. One-third of countries do not have legislation against marketing of unhealthy foods and beverages to children. Most countries reported routine assessment for developmental difficulties in children, but less than a quarter collected and reported data on children who are developmentally on track. There are major gaps in data collection for migrant children. Hospitalization rates for young children vary five-fold across the region, indicating over-hospitalization and access problems in some countries. Only ten countries allow minors access to health care without parental consent based on their maturity and only eleven countries allow school nurses to dispense contraceptives to adolescents without a doctor's prescription. Conclusions: This paper shows the progress in child and adolescent health made by countries in Europe until 2020 and key areas where additional work is needed to move the 2030 agenda forward. The survey was undertaken before the COVID-19 pandemic and the war in Ukraine. Both will likely exacerbate many of the observed problems and potentially reverse some gains reported. A renewed commitment is needed.


Subject(s)
Adolescent Health , COVID-19 , Adolescent , Humans , Child , Child, Preschool , Pandemics/prevention & control , COVID-19/epidemiology , Obesity , Europe
4.
Plant Dis ; 105(8): 2217-2221, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33141641

ABSTRACT

The increasing prevalence of the grapevine trunk diseases Eutypa and Botryosphaeria dieback has been attributed, in part, to abiotic stresses imposed on vineyards as production intensifies worldwide. The aim of this study was to evaluate the influence of water deficit irrigation practices on the infection of pruning wounds by Eutypa lata and Diplodia seriata and the subsequent rate of colonization. Two vineyard trials were conducted over two consecutive seasons in South Australia, one in the Riverland with 'Cabernet Sauvignon' with four irrigation treatments (100, 50, 25, and 12.5% of the standard irrigation program) and another in the Barossa Valley with 'Shiraz' on six rootstocks and own roots, either irrigated or not irrigated. According to leaf water potential assessments, vines with reduced irrigation were generally in water deficit and therefore subjected to stress. On the whole, incidence of wound infection and distance of colonization were similar between irrigation treatments for both pathogens, except in the Riverland, where E. lata colonized canes to a greater extent in well-watered vines than those in water deficit. Only vines on rootstock 'Ramsey' in the Barossa Valley had greater extent of colonization by E. lata in the nonirrigated vines. There was no correlation between internal staining and colonization, with both pathogens recovered to nearly 20 cm ahead of the staining. Water deficit did not increase the susceptibility of grapevine pruning wounds to infection or colonization of the subtending tissue by E. lata and D. seriata. In fact, there was evidence of lower susceptibility to colonization by E. lata in vines subjected to severe water deficit.


Subject(s)
Vitis , Ascomycota , Plant Diseases , Water
5.
Front Plant Sci ; 11: 553907, 2020.
Article in English | MEDLINE | ID: mdl-33013971

ABSTRACT

Environmental cues are known to alter the methylation profile of genomic DNA, and thereby change the expression of some genes. A proportion of such modifications may become adaptive by adjusting expression of stress response genes but others have been shown to be highly stochastic, even under controlled conditions. The influence of environmental flux on plants adds an additional layer of complexity that has potential to confound attempts to interpret interactions between environment, methylome, and plant form. We therefore adopt a positional and longitudinal approach to study progressive changes to barley DNA methylation patterns in response to salt exposure during development under greenhouse conditions. Methylation-sensitive amplified polymorphism (MSAP) and phenotypic analyses of nine diverse barley varieties were grown in a randomized plot design, under two salt treatments (0 and 75 mM NaCl). Combining environmental, phenotypic and epigenetic data analyses, we show that at least part of the epigenetic variability, previously described as stochastic, is linked to environmental micro-variations during plant growth. Additionally, we show that differences in methylation increase with time of exposure to micro-variations in environment. We propose that subsequent epigenetic studies take into account microclimate-induced epigenetic variability.

6.
Sci Rep ; 10(1): 15671, 2020 09 24.
Article in English | MEDLINE | ID: mdl-32973144

ABSTRACT

The collection of fungal spores by honey bees, Apis mellifera, can be classified as active or passive, the latter when spores are associated with pollen, nectar or honey dew. While low quality and shortage of pollen have been raised as hypotheses for fungal spore collection, the nutritional value of fungal spores for honey bees is poorly understood. Here we investigated the effect of consumption of fungal spores on survival, ovarian activation and the development of the hypopharyngeal glands (HPGs) in honey bee workers. Two pollen diets (Eucalyptus sp. pollen and a multifloral pollen) supplemented or not with spores of Botrytis cinerea, Cladosporium sp. or Colletotrichum acutatum were used. Consumption of diets that contained fungal spores increased the longevity of honey bee workers but had no significant effect on the development of their HPGs and ovaries. This demonstrates that fungal spores may have nutritional value for honey bees and that the consumption of fungal spores may compensate for nutritional imbalances of poor-quality pollen diets.


Subject(s)
Bees/microbiology , Nutrients/metabolism , Spores, Fungal/metabolism , Animals , Bees/growth & development , Diet , Female , Hypopharynx/growth & development , Ovary/growth & development
7.
J Adolesc ; 76: 30-36, 2019 10.
Article in English | MEDLINE | ID: mdl-31442812

ABSTRACT

INTRODUCTION: A systematic review of trusted adult interventions for adolescents revealed that there was no common terminology, agreed explicit definition, or detail, regarding the personal qualities, functions and roles fulfilled by trusted adults that was used consistently across the papers. To provide clarity, we therefore aimed to produce a taxonomy of trusted adult input, using evidence drawn from our review. METHODS: Data from the review findings were used to compile the taxonomy, moving from the general to the more specific, in a four stage process. This involved: (1) compilation of elements described in individual papers, (2) grouping of elements derived from stage 1 into categories, (3) examination of context and nature of the relationship, (4) development of a categorisation of trusted adult input. FINDINGS: The resulting taxonomy encapsulates core essential qualities provided by people acting in trusted adult or mentoring roles, and gives details relating to what a young person might expect from individuals they put their trust in. The taxonomy consists of six categories relating to: delivery context, roles of trusted adults, nature of support, personal qualities, actions/functions, and impact. CONCLUSIONS: The taxonomy describes key elements that define the trusted adult role, and has the potential to inform the development of policies and guidelines relating to support provision. It may be used as a framework for the reporting of trusted adult interventions within research, and act as a helpful guide if a young person is in doubt about the behaviour or qualities displayed by an adult in their environment.


Subject(s)
Adolescent Development , Mentors/classification , Adolescent , Adult , Female , Humans , Trust
8.
Syst Rev ; 7(1): 207, 2018 11 24.
Article in English | MEDLINE | ID: mdl-30474574

ABSTRACT

BACKGROUND: Although documentation of harm towards children and young people has existed for centuries, it was not until the 1960s that it became a specific focus for health professionals. Since that time, the importance of protective social networks has become better understood. The concept of trusted adults has come into sharper focus, with children being encouraged to develop networks of dependable adults to turn to for support in times of need. While many child protection processes highlight risks to younger children, there has been less emphasis on older children. The role of trusted adults may be particularly important during adolescence, due to burgeoning independence, developing sexuality, relationship formation, and associated vulnerabilities. While important choices relating to health and education are made during this period, there is little formal evidence relating to the impact of trusted adults on such outcomes. This review therefore aims to focus on the role and influence of trusted adults for adolescents. METHODS: This study is a scoping review. A broad range of databases will be searched, including MEDLINE, ERIC, Education Abstracts, Web of Science, ASSIA, Sociological Abstracts, and PsycINFO. Predefined inclusion/exclusion criteria will be used, with a focus on outcomes relating to health and education. Two reviewers will blind screen papers independently at all screening stages, with conflicts being resolved by a third reviewer. Quantitative and qualitative studies, as well as unpublished (grey) literature/reports, will be included. We will use the World Health Organization's 'second decade' definition of adolescence. We aim to collate and map evidence in a broad overview and produce meta-analyses of homogenous data. Where this is not possible, a narrative summary will be produced. DISCUSSION: There appears to be sparse knowledge regarding the role of trusted adults for adolescents. Potential benefits to health and wellbeing may impact on educational attainment, and vice versa. These areas are of particular relevance during the second decade, when decisions that affect future direction, achievement, and wellbeing are being made. The increased understanding of the role of trusted adults provided by this review may help to inform practice and policy and lead to potential benefits for the health and education of adolescents. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD 42017076739.


Subject(s)
Adolescent Behavior/psychology , Health Status , Interpersonal Relations , Social Support , Trust , Adolescent , Educational Status , Harm Reduction , Health Personnel/psychology , Humans , Mental Health
9.
Int J Palliat Nurs ; 24(11): 548-557, 2018 Nov 02.
Article in English | MEDLINE | ID: mdl-30457462

ABSTRACT

BACKGROUND:: Acute hospitals provide a high proportion of end-of-life care but some families experience poor communication with clinical staff. AIM:: To evaluate the use of the Family's Voice diary communication tool across nine healthcare settings. METHODS:: A mixed method practice development approach was used incorporating: an audit of the usage of Family's Voice; collation and analysis of written comments; and collation of written feedback from the principal investigators at data collection sites. FINDINGS:: There were 112 completed diaries. Families rated pain and vomiting as well controlled, but agitation and breathlessness were difficult to control. Families were positive about care provided to the patients and themselves. Ten themes were identified from analysis of the families' written comments that echoed national concerns. CONCLUSION:: Evidence for the utility of the diary is building. Future work could focus on strategies for embedding the diary into routine care for all end-of-life patients.


Subject(s)
Communication , Diaries as Topic , Family , Palliative Care , Professional-Family Relations , Humans , Pain Management
10.
Plant Methods ; 13: 47, 2017.
Article in English | MEDLINE | ID: mdl-28630643

ABSTRACT

BACKGROUND: Hyperspectral imaging is an emerging means of assessing plant vitality, stress parameters, nutrition status, and diseases. Extraction of target values from the high-dimensional datasets either relies on pixel-wise processing of the full spectral information, appropriate selection of individual bands, or calculation of spectral indices. Limitations of such approaches are reduced classification accuracy, reduced robustness due to spatial variation of the spectral information across the surface of the objects measured as well as a loss of information intrinsic to band selection and use of spectral indices. In this paper we present an improved spatial-spectral segmentation approach for the analysis of hyperspectral imaging data and its application for the prediction of powdery mildew infection levels (disease severity) of intact Chardonnay grape bunches shortly before veraison. RESULTS: Instead of calculating texture features (spatial features) for the huge number of spectral bands independently, dimensionality reduction by means of Linear Discriminant Analysis (LDA) was applied first to derive a few descriptive image bands. Subsequent classification was based on modified Random Forest classifiers and selective extraction of texture parameters from the integral image representation of the image bands generated. Dimensionality reduction, integral images, and the selective feature extraction led to improved classification accuracies of up to [Formula: see text] for detached berries used as a reference sample (training dataset). Our approach was validated by predicting infection levels for a sample of 30 intact bunches. Classification accuracy improved with the number of decision trees of the Random Forest classifier. These results corresponded with qPCR results. An accuracy of 0.87 was achieved in classification of healthy, infected, and severely diseased bunches. However, discrimination between visually healthy and infected bunches proved to be challenging for a few samples, perhaps due to colonized berries or sparse mycelia hidden within the bunch or airborne conidia on the berries that were detected by qPCR. CONCLUSIONS: An advanced approach to hyperspectral image classification based on combined spatial and spectral image features, potentially applicable to many available hyperspectral sensor technologies, has been developed and validated to improve the detection of powdery mildew infection levels of Chardonnay grape bunches. The spatial-spectral approach improved especially the detection of light infection levels compared with pixel-wise spectral data analysis. This approach is expected to improve the speed and accuracy of disease detection once the thresholds for fungal biomass detected by hyperspectral imaging are established; it can also facilitate monitoring in plant phenotyping of grapevine and additional crops.

11.
Plant Dis ; 97(12): 1599-1604, 2013 Dec.
Article in English | MEDLINE | ID: mdl-30716838

ABSTRACT

Eutypa dieback threatens the sustainability of vineyards worldwide and limited treatments are available for control of the disease in grapevine. Following the loss of the effective benzimidazole fungicides, benomyl and carbendazim, there is a need to identify alternatives for the protection of pruning wounds against infection by ascospores of Eutypa lata. In this study, 24 fungicide and natural treatments were evaluated in the laboratory and field. Tebuconazole and carbendazim were the most effective fungicides for reducing colonization of pruning wounds inoculated with E. lata. Pyrimethanil and fluazinam also provided some control but were less effective than tebuconazole at the rates tested. Other treatments, such as cyprodinil + fludioxionil, pyraclostrobin, a garlic extract, and lactoferrin, reduced colonization of wounds by E. lata but require further evaluation at higher concentrations. Carbendazim applied to pruning wounds using tractor-driven sprayers reduced the incidence of pruning wound infection by E. lata to levels similar to that achieved by application with a paint brush.

12.
Am J Manag Care ; 18(12): 838-44, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23286612

ABSTRACT

OBJECTIVES: To determine if post-discharge telephonic case management (CM) reduces emergent hospital readmissions for select high-risk patients. STUDY DESIGN: Prospective, randomized. METHODS: We conducted a prospective, randomized control study of the effect of hospital discharge planning from health plan telephonic case managers on readmissions for high-risk patients. High risk was defined as having an initial discharge major diagnosis of gastrointestinal, heart, or lower respiratory and length of stay of 3 days or more. The intervention group (N = 1994) received telephonic outreach and engagement within 24 hours of discharge and their calls were made in descending risk order to engage the highest risk first. The control group (N = 1994) received delayed telephonic outreach and engagement 48 hours after discharge notification and no call order by risk was applied. Comparison groups had statistically equivalent characteristics at baseline (P > .05). RESULTS: The intent-to-treat 60-day readmission rate for the treatment group was 7.4% versus 9.6% for the control group (P = .01), representing a 22% relative reduction in all-cause readmissions. Two post hoc assessments were conducted to identify potential mechanisms of action for this effect and showed that the treatment group had more physician visits and prescription drug fills following initial discharge. CONCLUSIONS: Telephonic CM reduces the likelihood of 60-day readmissions for select high-risk patients. This study suggests that prioritizing telephonic outreach to a select group of highrisk patients based on their discharge date and risk severity is an effective case management strategy. Future studies should explore patients' activity beyond phone calls to further explain the mechanism for readmission reduction.


Subject(s)
Case Management/organization & administration , Case Management/statistics & numerical data , Patient Discharge , Patient Readmission/statistics & numerical data , Telephone , Age Factors , Female , Humans , Length of Stay , Male , Prospective Studies , Risk Factors , Sex
13.
Mol Plant Pathol ; 11(5): 691-704, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20696006

ABSTRACT

Mycosphaerella graminicola is a major pathogen of wheat worldwide, causing Septoria leaf blotch disease. Targeted gene disruption in M. graminicola, by Agrobacterium tumefaciens-mediated transformation, has become an established functional genomics tool for M. graminicola research in recent years. However, in order to advance research into this economically important pathogen, further functional genomics tools need to be developed. Here, we report three new capabilities for M. graminicola research: (i) two selectable markers have been shown to work robustly in M. graminicola, namely G418 and the fungicide carboxin; (ii) the generation of a strain of M. graminicola in which the KU70 (MUS-51) homologue has been disrupted; in this strain, homologous recombination efficiencies increased to more than 95%, whilst maintaining wild-type growth in vitro and full pathogenicity on wheat leaves; (iii) the ability to efficiently target and generate precise mutations of specific genes in the genomic context in M. graminicola. In addition, the insertion of the E198A mutation into the beta-tubulin gene (MgTUB1), conferring resistance to the fungicide benomyl, suggests that this mutant allele may provide an additional selectable marker. The collective use of these tools will permit further advancements in our knowledge of the biology and pathogenicity of this important plant pathogen.


Subject(s)
Ascomycota/genetics , Genetic Research , Alleles , Analysis of Variance , Antigens, Nuclear/chemistry , Antigens, Nuclear/genetics , Ascomycota/drug effects , Ascomycota/growth & development , Benomyl/pharmacology , Blotting, Southern , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/genetics , Drug Resistance, Fungal/drug effects , Drug Resistance, Fungal/genetics , Gene Deletion , Gene Targeting , Genetic Loci/genetics , Genetic Markers , Ku Autoantigen , Mutagenesis, Insertional/genetics , Phenotype , Point Mutation/genetics , Recombination, Genetic/drug effects , Recombination, Genetic/genetics , Reproducibility of Results , Selection, Genetic/drug effects , Sequence Homology, Amino Acid , Transformation, Genetic/drug effects , Tubulin/genetics
14.
Nurs Stand ; 24(25): 42-7, 2010.
Article in English | MEDLINE | ID: mdl-20306843

ABSTRACT

This article discusses the role of the ophthalmic nurse in the care of patients with wet age-related macular degeneration who are undergoing intra-vitreal therapy. It provides an overview of the condition, its classification, clinical features, aetiology, diagnosis and treatment, and explains the implications for future nursing practice. A proactive, evidence-based and holistic approach to nursing care is emphasised throughout the article.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Nurse's Role , Wet Macular Degeneration/therapy , Antibodies, Monoclonal, Humanized , Evidence-Based Nursing , Health Promotion , Holistic Nursing , Humans , Injections, Intraocular/methods , Injections, Intraocular/nursing , Patient Education as Topic , Ranibizumab , Social Support , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vitreous Body , Wet Macular Degeneration/diagnosis , Wet Macular Degeneration/etiology
15.
Syst Appl Microbiol ; 32(8): 549-57, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19748753

ABSTRACT

Strains of Xanthomonas translucens have caused dieback in the Australian pistachio industry for the last 15 years. Such pathogenicity to a dicotyledonous woody host contrasts with that of other pathovars of X. translucens, which are characterized by their pathogenicity to monocotyledonous plant families. Further investigations, using DNA-DNA hybridization, gyrB gene sequencing and integron screening, were conducted to confirm the taxonomic status of the X. translucens pathogenic to pistachio. DNA-DNA hybridization provided a clear classification, at the species level, of the pistachio pathogen as a X. translucens. In the gyrB-based phylogeny, strains of the pistachio pathogen clustered among the X. translucens pathovars as two distinct lineages. Integron screening revealed that the cassette arrays of strains of the pistachio pathogen were different from those of other Xanthomonas species, and again distinguished two groups. Together with previously reported pathogenicity data, these results confirm that the pistachio pathogen is a new pathovar of X. translucens and allow hypotheses about its origin. The proposed name is Xanthomonas translucens pv. pistaciae pv. nov.


Subject(s)
Pistacia/microbiology , Xanthomonas/genetics , Bacterial Proteins/genetics , Cluster Analysis , DNA Gyrase/genetics , Integrons/genetics , Nucleic Acid Hybridization , Phylogeny , Xanthomonas/classification , Xanthomonas/pathogenicity
16.
Phytopathology ; 99(8): 985-95, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19594318

ABSTRACT

Almond anthracnose was reported for the first time in Australia in 1998 and has since been observed in all of the major almond-growing regions. The organism causing anthracnose was confirmed as Colletotrichum acutatum using taxon-specific polymerase chain reaction (PCR). Three main morphotypes of C. acutatum from almond in Australia were identified (namely, pink, orange, and cream colony color) and the optimum temperature for mycelial growth of representative isolates was 25 degrees C. Australian isolates of C. acutatum were more similar morphologically to the pink subpopulation of C. acutatum from California than to the gray Californian subpopulation and the isolates of Colletotrichum from Israel. Inter-simple-sequence-repeat (ISSR) PCR analysis revealed that the majority of Australian isolates shared an identical banding pattern whereas Australian isolates of C. acutatum from almond were distinct from isolates of the pink and gray subpopulations of C. acutatum from almond in California and of Colletotrichum spp. from almond in Israel. Sequence analysis of the internally transcribed spacer (ITS1-2) ribosomal DNA region of representative isolates differed from the results of ISSR-PCR in that polymorphisms were revealed among isolates, indicating that some genetic variation may be present. Pathogenicity experiments on detached leaves and fruit revealed pathogenic variation among representative isolates of C. acutatum from almond in Australia, California, and Israel; however, all isolates tested caused disease. Distinct subgroups among Australian isolates of C. acutatum from almond were not supported on the basis of morphology, mycelial growth rates, ISSR-PCR, and pathogenicity.


Subject(s)
Colletotrichum/genetics , Colletotrichum/pathogenicity , Plant Diseases/microbiology , Prunus/microbiology , Australia , Colletotrichum/cytology , Phylogeny
18.
Int J Food Microbiol ; 119(1-2): 84-8, 2007 Oct 20.
Article in English | MEDLINE | ID: mdl-17765989

ABSTRACT

Many fungi may occur on grapes during growth in the vineyard, but the main concern from the viewpoint of mycotoxin contamination is the black Aspergilli, Aspergillus carbonarius and A. niger. These fungi are capable of producing ochratoxin A (OA) which may contaminate grapes and grape products such as wine, grape juice and dried vine fruit. Understanding the ecology and physiology of the black Aspergilli can provide tools for management of OA at all stages of grape production and processing. In the vineyard, careful management of cultivation, irrigation and pruning can assist in minimising the levels of black Aspergilli in the soil, which in turn, can minimise contamination of grapes by these fungi. Minimising damage to grapes on the vine by the use of open vine canopies, grape varieties with resistance to rain damage and by the management of insect pests and fungal diseases (e.g., mildew, Botrytis bunch rot) can reduce the incidence of Aspergillus rot in mature berries. The risk of OA in table grapes can be minimised by careful visual inspection to avoid damaged and discoloured berries. In wine, harvesting grapes with minimal damage, rapid processing and good sanitation practices in the winery assist in minimising OA. During vinification, pressing of grapes, and clarification steps which remove grape solids, grape proteins and spent yeast can also remove a significant proportion of OA. For dried vine fruit production, avoiding berry damage, rapid drying, and final cleaning and sorting to remove dark berries can reduce overall OA levels in finished products.


Subject(s)
Aspergillus/growth & development , Food Contamination/analysis , Food Handling/methods , Ochratoxins/analysis , Vitis , Aspergillus/metabolism , Aspergillus niger/growth & development , Aspergillus niger/metabolism , Beverages/analysis , Food Contamination/prevention & control , Food Microbiology , Ochratoxins/biosynthesis , Ochratoxins/toxicity , Plant Diseases/microbiology , Vitis/chemistry , Vitis/microbiology , Wine/analysis
19.
Mycol Res ; 111(Pt 8): 891-900, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17707626

ABSTRACT

A collection of isolates of Rhizoctonia solani anastomosis group (AG) 2 was examined for genetic diversity and pathogenicity. Anastomosis reactions classified the majority of isolates into the known subgroups of AG 2-1 and AG 2-2 but the classification of several isolates was ambiguous. Morphological characters were consistent with the species, with no discriminating characters existing between subgroups. Vertical PAGE of pectic enzymes enabled the separation of zymogram group (ZG) 5 and 6 within AG 2-1, but not the separation of ZG 4 and 10 within AG 2-2. PCR analysis using inter-simple sequence repeats (ISSR) and the intron-splice junction (ISJ) region supported the separation of ZG 5 and 6, while the AG 2-2 isolates were separated by geographic region. A comparison of distance matrices produced by the zymogram analysis and PCR indicated a strong correlation between the marker types. Pathogenicity studies suggested canola (Brassica napus) cultivars were most severely affected by AG 2-1, while cultivars of two species of medic (Medicago truncatula cv. Caliph and M. littoralis cv. Herald) were susceptible to both AG 2-1 and 2-2. The results indicate that AG 2 is a polyphyletic group in which the classification of subtypes is sometimes difficult. Further investigation of the population structure within Australia is required to determine the extent and origin of the observed diversity.


Subject(s)
Genetic Variation , Rhizoctonia , Solanum tuberosum/microbiology , Brassica/microbiology , DNA, Bacterial/analysis , Electrophoresis, Agar Gel , Genotype , Isoenzymes , Medicago/microbiology , Pectins/metabolism , Plant Diseases/microbiology , Polymerase Chain Reaction , Rhizoctonia/classification , Rhizoctonia/genetics , Rhizoctonia/isolation & purification , Rhizoctonia/pathogenicity , South Australia , Species Specificity
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