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1.
Phytopathology ; 112(8): 1710-1722, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35240867

RESUMO

Trunk and scaffold canker diseases (TSCDs) of almond cause significant yield and tree losses and reduce the lifespan of orchards. In California, several pathogens cause TSCDs, including Botryosphaeriaceae, Ceratocystis destructans, Eutypa lata, Collophorina hispanica, Pallidophorina paarla, Cytospora, Diaporthe, and Phytophthora spp. Field diagnosis of TSCDs is challenging because symptom delineation among the diseases is not clear. Accurate diagnosis of the causal species requires detailed examination of symptoms and subsequent isolation on medium and identification using morphological criteria and subsequent confirmation using molecular tools. The process is time-consuming and difficult, particularly as morphological characteristics are variable and overlap among species. To facilitate diagnosis of TSCD, we developed PCR assays using 23 species-specific primers designed by exploiting sequence differences in the translation elongation factor, ß-tubulin, or internal transcribed spacer gene. Using genomic DNA from pure cultures of each fungal and oomycete species, each primer pair successfully amplified a single DNA fragment from the target pathogen but not from selected nontarget pathogens or common endophytes. Although 10-fold serial dilution of fungal DNA extracted from either pure cultures or infected wood samples detected as little as 0.1 pg of DNA sample, consistent detection required 10 ng of pathogen DNA from mycelial samples or from wood chips or drill shavings from artificially or naturally infected almond wood samples with visible symptoms. The new PCR assay represents an improved tool for diagnostic laboratories and will be critical to implement effective disease surveillance and control measures.


Assuntos
Prunus dulcis , DNA Fúngico/genética , Filogenia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , Prunus dulcis/genética
2.
Plant Dis ; 105(11): 3368-3375, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33560878

RESUMO

Almond trunk and branch canker diseases constitute a major cause of tree mortality in California. Numerous fungal pathogens have been associated with these canker diseases and pruning wounds act as major infection courts. Before this study, there were no products registered in California for the management of these diseases. In this study, fungicidal products including synthetic chemistries, biocontrols, paint, and a sealant were evaluated for preventing fungal pathogen infection via pruning wounds. In four field trials conducted over two dormant seasons, 16 pruning wound treatments were tested using handheld spray applications against five almond canker pathogens, namely Botryosphaeria dothidea, Neofusicoccum parvum, Cytospora sorbicola, Ceratocystis destructans, and Eutypa lata. The fungicide thiophanate-methyl (Topsin M; United Phosphorus, Bandra West, Mumbai, India) provided 82% overall disease prevention against four fungal pathogens. The biological control agent, Trichoderma atroviride SC1 (Vintec; Bi-PA, Londerzeel, Belgium), tested at three application rates, resulted in 90 to 93% protection of pruning wounds in field trials, and for individual pathogens ranged from 81 to 100% protection for the three rates. At the time of this publication, Vintec is being considered for registration as a biological control product for the prevention of almond canker diseases, while Topsin M is recommended to growers for the prevention of almond canker diseases. This research indicates that effective protection of pruning wounds from infection by almond canker pathogens can be achieved with a one-time spray application of thiophanate-methyl or the biocontrol T. atroviride SC1 (recommended 2 g/liter) after pruning.


Assuntos
Fungicidas Industriais , Doenças das Plantas , Prunus dulcis , Agentes de Controle Biológico , Fungicidas Industriais/farmacologia , Doenças das Plantas/prevenção & controle , Prunus dulcis/microbiologia
3.
Plant Dis ; 105(2): 346-360, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32757731

RESUMO

Almond canker diseases are destructive and can reduce the yield as well as the lifespan of almond orchards. These diseases may affect the trunk and branches of both young and mature trees and can result in tree death soon after orchard establishment in severe cases. Between 2015 and 2018, 70 almond orchards were visited throughout the Central Valley of California upon requests from farm advisors for canker disease diagnosis. Two major canker diseases were identified, including Botryosphaeriaceae cankers and Ceratocystis canker. In addition, five less prevalent canker diseases were identified, including Cytospora, Eutypa, Diaporthe, Collophorina, and Pallidophorina canker. Seventy-four fungal isolates were selected for multilocus phylogenetic analyses of internal transcribed spacer region ITS1-5.8S-ITS2 and part of the translation elongation factor 1-α, ß-tubulin, and glyceraldehyde 3-phosphate dehydrogenase gene sequences; 27 species were identified, including 12 Botryosphaeriaceae species, Ceratocystis destructans, five Cytospora species, Collophorina hispanica, four Diaporthe species, two Diatrype species, Eutypa lata, and Pallidophorina paarla. The most frequently isolated species were Ceratocystis destructans, Neoscytalidium dimidiatum, and Cytospora californica. Pathogenicity experiments on almond cultivar Nonpareil revealed that Neofusicoccum parvum, Neofusicoccum arbuti, and Neofusicoccum mediterraneum were the most virulent. Botryosphaeriaceae cankers were predominantly found in young orchards and symptoms were most prevalent on the trunks of trees. Ceratocystis canker was most commonly found in mature orchards and associated with symptoms found on trunks or large scaffold branches. This study provides a thorough examination of the diversity and pathogenicity of fungal pathogens associated with branch and trunk cankers of almond in California.


Assuntos
Prunus dulcis , Ascomicetos , California , DNA Fúngico/genética , Filogenia , Doenças das Plantas
4.
Plant Dis ; 103(9): 2397-2411, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322495

RESUMO

A survey was conducted during 2015 and 2016 in pistachio orchards throughout the San Joaquin Valley of California to investigate the occurrence of canker diseases and identify the pathogens involved. Cankers and dieback symptoms were observed mainly in orchards aged >15 years. Symptoms of canker diseases included brown to dark brown discoloration of vascular tissues, wood necrosis, and branch dieback. In total, 58 fungal isolates were obtained from cankers and identified based on multilocus phylogenetic analyses (internal transcribed spacer, glyceraldehyde 3-phosphate dehydrogenase, ß-tubulin, calmodulin, actin 1, and translation elongation factor 1α) representing 11 fungal species: Colletotrichum karstii, Cytospora californica, Cytospora joaquinensis, Cytospora parapistaciae, Cytospora pistaciae, Diaporthe ambigua, Didymella glomerata, Diplodia mutila, Neofusicoccum mediterraneum, Phaeoacremonium canadense, and Schizophyllum commune. Pathogenicity tests conducted in the main pistachio cultivars Kerman, Golden Hills, and Lost Hills using the mycelium-plug method indicated that all fungal species were pathogenic to Pistacia vera. All species tested caused cankers in pistachio branches, although virulence among species varied from high to moderate. Overall, N. mediterraneum and Cytospora spp. were the most widespread and virulent species associated with canker diseases of pistachio in California.


Assuntos
Fungos , Pistacia , Virulência , California , Fungos/patogenicidade , Fungos/fisiologia , Filogenia , Pistacia/classificação , Pistacia/microbiologia , Doenças das Plantas/microbiologia
5.
IMA Fungus ; 9: 333-370, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30622886

RESUMO

Cytospora species are destructive canker and dieback pathogens of woody hosts in natural and agroecosystems around the world. In this genus, molecular identification has been limited due to the paucity of multi-locus sequence typing studies and the lack of sequence data from type specimens in public repositories, stalling robust phylogenetic reconstructions. In most cases a morphological species concept could not be applied due to the plasticity of characters and significant overlap of morphological features such as spore dimensions and fruiting body characters. In this study, we employed a molecular phylogenetic framework with the inclusion of four nuclear loci (ITS, translation elongation factor 1-alpha, actin, and beta-tubulin) to unveil the biodiversity and taxonomy of this understudied important genus of plant pathogens. Phylogenetic inferences based on 150 Californian isolates revealed 15 Cytospora species associated with branch and twig cankers and dieback of almond, apricot, cherry, cottonwood, olive, peach, pistachio, plum, pomegranate, and walnut trees in California. Of the 15 species recovered in this study, 10 are newly described and typified, in addition to one new combination. The pathogenic status of the newly described Cytospora species requires further investigation as most species were associated with severe dieback and decline of diverse and economically important fruit and nut crops in California.

6.
Am J Disaster Med ; 12(2): 107-134, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29136272

RESUMO

The current hyper-volatile, -uncertain, -complex, and -ambiguous (VUCA) threat environment demands a more cohesive support structure for crisis leaders who may be faced with crises of increasing magnitude and frequency and, in some instances, multiple crisis events simultaneously. The project team investigates the perceptions of crisis leaders regarding establishing a crisis leader advisor position for crisis leaders to benefit from their experience while prosecuting crisis response activities. The team linked hyper-VUCA crises, crisis response frameworks, meta-leadership, crisis leader attributes, and advisor attributes. The overall goal of the project is to increase the ability of the crisis leaders to more effectively and efficiently navigate crisis events resulting in more efficient and effective response and recovery. Three research questions were developed to assess the following: thoughts of integrating a crisis leader advisor position; development of a crisis leader advisor certification program; and attributes of crisis leader advisors. A qualitative research methodology using a phenomenological approach was employed. Forty-one participants were purposefully selected and administered a short, online survey consisting of 11 questions. Data were analyzed using percentage analysis, weighted sums, and inductive thematic analysis. The project team found an overwhelming support for the crisis leader advisor position and the crisis leader advisor certification program. Additionally, experience and trustworthiness ranked among the top sought after attributes of a crisis leader advisor. The team recommendations included (1) implement a crisis leaders advisor guide/framework; (2) create a formal crisis leader advisor position in national incident management system; (3) implement a crisis leader advisor certification framework; (4) benchmark established advisor programs; and (5) implement a framework to match leaders and advisors.


Assuntos
Planejamento em Desastres/organização & administração , Serviços Médicos de Emergência/organização & administração , Liderança , Equipe de Assistência ao Paciente/organização & administração , Competência Profissional , Adulto , Desastres , Eficiência Organizacional , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Incerteza
7.
J Emerg Manag ; 15(3): 139-155, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28829528

RESUMO

The current hyper-volatile, -uncertain, -complex, and -ambiguous (VUCA) threat environment demands a more cohesive support structure for crisis leaders who may be faced with crises of increasing magnitude and frequency and, in some instances, multiple crisis events simultaneously. The project team investigates the perceptions of crisis leaders regarding establishing a crisis leader advisor position for crisis leaders to benefit from their experience while prosecuting crisis response activities. The team linked hyper-VUCA crises, crisis response frameworks, meta-leadership, crisis leader attributes, and advisor attributes. The overall goal of the project is to increase the ability of the crisis leaders to more effectively and efficiently navigate crisis events resulting in more efficient and effective response and recovery. Three research questions were developed to assess the following: thoughts of integrating a crisis leader advisor position; development of a crisis leader advisor certification program; and attributes of crisis leader advisors. A qualitative research methodology using a phenomenological approach was employed. Forty-one participants were purposefully selected and administered a short, on-line survey consisting of 11 questions. Data were analyzed using percentage analysis,weighted sums, and inductive thematic analysis. The project team found an overwhelming support for the crisis leader advisor position and the crisis leader advisor certification program. Additionally, experience and trustworthiness ranked among the top sought after attributes of a crisis leader advisor. The team recommendations included (1) implement a crisis leaders advisor guide/framework; (2) create a formal crisis leader advisor position in national incident management system; (3) implement a crisis leader advisor certification framework; (4) benchmark established advisor programs; and (5) implement a framework to match leaders and advisors.


Assuntos
Planejamento em Desastres , Desastres , Emergências , Liderança , Humanos , Pesquisa Qualitativa , Incerteza
8.
J Emerg Manag ; 15(2): 117-132, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28820230

RESUMO

The current hyper-volatile, -uncertain, -complex, and -ambiguous (VUCA) threat environment demands a more cohesive support structure for crisis leaders who may be faced with crises of increasing magnitude and frequency and, in some instances, multiple crisis events simultaneously. The project team investigates the perceptions of crisis leaders regarding establishing a crisis leader advisor position for crisis leaders to benefit from their experience while prosecuting crisis response activities. The team linked hyper-VUCA crises, crisis response frameworks, meta-leadership, crisis leader attributes, and advisor attributes. The overall goal of the project is to increase the ability of the crisis leaders to more effectively and efficiently navigate crisis events resulting in more efficient and effective response and recovery. Three research questions were developed to assess the following: thoughts of integrating a crisis leader advisor position; development of a crisis leader advisor certification program; and attributes of crisis leader advisors. A qualitative research methodology using a phenomenological approach was employed. Forty-one participants were purposefully selected and administered a short, on-line survey consisting of 11 questions. Data were analyzed using percentage analysis, weighted sums, and inductive thematic analysis. The project team found an overwhelming support for the crisis leader advisor position and the crisis leader advisor certification program. Additionally, experience and trustworthiness ranked among the top sought after attributes of a crisis leader advisor. The team recommendations included (1) implement a crisis leaders advisor guide/framework; (2) create a formal crisis leader advisor position in national incident management system; (3) implement a crisis leader advisor certification framework; (4) benchmark established advisor programs; and (5) implement a framework to match leaders and advisors.


Assuntos
Planejamento em Desastres , Desastres , Emergências , Liderança , Humanos , Pesquisa Qualitativa , Mídias Sociais , Terrorismo , Incerteza , Violência , Tempo (Meteorologia)
10.
J Occup Environ Med ; 57 Suppl 3: S12-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25741609

RESUMO

BACKGROUND: Federal Employees' Compensation Act injury rates and claim costs benefit from injury prevention and case management efforts. The Department of Labor Protecting Our Workers and Ensuring Reemployment data on lost time injuries and illnesses do support injury prevention and case management activities. METHODS: The management efforts of the Department of Defense, Veterans Administration, and Department of Labor were examined to determine whether more is needed to support injury prevention and case management efforts. RESULTS: Data on Protecting Our Workers and Ensuring Reemployment goal 3 metrics should be provided to safety and occupational health (SOH) personnel to support injury prevention and case management efforts. DISCUSSION: Injury prevention and case management data need to be made available to SOH team members to prevent injuries and lower claims costs. CONCLUSION: Actionable information must be provided to SOH that will facilitate case management and injury prevention programs and lower costs.


Assuntos
Governo Federal , Saúde Ocupacional , Traumatismos Ocupacionais/prevenção & controle , United States Department of Defense/organização & administração , United States Department of Veterans Affairs/organização & administração , Indenização aos Trabalhadores/organização & administração , Administração de Caso , Controle de Custos , Humanos , Gestão da Segurança , Estados Unidos , United States Department of Defense/economia , United States Department of Veterans Affairs/economia , Indenização aos Trabalhadores/economia
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