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1.
J Adv Nurs ; 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38444126

RESUMEN

OBJECTIVE: To analyse the influence of the COVID-19 pandemic and the perception of self-efficacy on the health professionals of the Spanish out-of-hospital emergency services. DESIGN: Observational, cross-sectional and descriptive with a survey methodology of 1710 participants from Spain (1 February-30 April, 2021). METHODS: The mental health of healthcare workers was assesed in terms of stress, anxiety and depression, as well as their self-efficacy. Linear and logistic regression models were fitted to predict these variables. A moderation analysis was conducted to determine the effect of self-efficacy on mental health. RESULTS: The means of the sample for stress, anxiety, depression and self-efficacy were 20.60, 15.74, 13.07 and 70.87, respectively. In the regression models, being a woman was the most significant factor for severe mental health impairment. Female gender was also a relevant factor for self-efficacy. Self-efficacy had a direct effect on the mental health for working in patient care. CONCLUSIONS: Healthcare workers showed moderate stress, severe anxiety, mild depression and good self-efficacy. Direct patient care was associated with more stress and severe anxiety. Age, female gender, job changes and job adjustment were associated with levels of stress, anxiety and depression. Self-efficacy is a determining factor of mental health in the direct care modality. IMPLICATIONS: The mental health of healthcare workers has been of great importance in the aftermath of the pandemic, but out-of-hospital emergency workers have been neglected in research. The levels of stress, anxiety and depression during the pandemic justify the creation of prevention and early diagnosis programmes, as they are essential in a health disaster. Surprisingly, their high level of perceived self-efficacy directly impact on the mental health of patient helthcare workers, so improving it will reduce the psychological risk. REPORTING METHOD: We have followed the STROBE guidelines. It has been partially funded by the Asistencia Sanitanitaria Interprovincial de Seguros - ASISA Foundation (Spain). PATIENT OR PUBLIC CONTRIBUTION: 'No patient or public involvement'.

2.
Arch Public Health ; 82(1): 15, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38291523

RESUMEN

BACKGROUND: The COVID-19 pandemic had a major psychological impact on health care workers (HCWs). This study was embedded in a larger quantitative study on the mental health care of out-of-hospital HCWs in Spain. To better understand this, a qualitative study was conducted to explore the experiences, coping strategies, and influencing factors of out-of-hospital HCWs who scored high (> 25 points) on the Depression Anxiety Stress Scale (DASS-21) in a previous quantitative mental health study. METHODS: A qualitative study was conducted using six in-depth interviews with individuals who scored high on the depression scale and agreed to be contacted by email between May and June 2021, using the phenomenological approach. The data were analysed using Brawn and Clare's method. RESULTS: The main results findings related to four themes. The emotional impact of assuming a professional role with high self-demands and responsibilities; Factors influencing the development of negative emotions such as the cruelty of the pandemic, the helplessness in relation to health management and policy, the changing role of the professional and the relationship with society; Personal protection through coping strategies to manage negative emotions such as support from colleagues and family; Good practices for the future looking for different management strategies that can influence individuals and their personal, professional, and social relationships. CONCLUSION: The strong impact of the circumstances experienced points to the need to develop psychological support programmes that can protect people's mental health from depression during a crisis and improve the relationship between workers and their managers.


RESUMEN: ANTECEDENTES: La pandemia de COVID-19 tuvo un gran impacto psicológico en el personal sanitario. Este estudio forma parte de un estudio cuantitativo más amplio sobre la atención a la salud mental de los trabajadores sanitarios extrahospitalarios en España. Para comprenderlo mejor, se llevó a cabo un estudio cualitativo para explorar las experiencias, estrategias de afrontamiento y factores de influencia de los trabajadores extrahospitalarios que obtuvieron puntuaciones altas (> 25 puntos) en la Escala de Depresión, Ansiedad y Estrés (DASS-21) en un estudio cuantitativo previo sobre salud mental. MéTODOS: Se realizó un estudio cualitativo mediante seis entrevistas en profundidad con individuos que puntuaron alto en la escala de depresión y aceptaron ser contactados por correo electrónico entre mayo y junio de 2021, utilizando el enfoque fenomenológico. Los datos se analizaron utilizando el método de Brawn y Clare. RESULTADOS: Los principales hallazgos de los resultados se relacionaron con cuatro temas. El impacto emocional de asumir un rol profesional con altas autoexigencias y responsabilidades; Factores que influyen en el desarrollo de emociones negativas como la crueldad de la pandemia, la impotencia en relación con la gestión y la política sanitaria, el papel cambiante del profesional y la relación con la sociedad; Protección personal a través de estrategias de afrontamiento para gestionar las emociones negativas como el apoyo de los compañeros y la familia; Buenas prácticas para el futuro buscando diferentes estrategias de gestión que puedan influir en los individuos y en sus relaciones personales, profesionales y sociales. CONCLUSIóN: El fuerte impacto de las circunstancias vividas apunta a la necesidad de desarrollar programas de apoyo psicológico que puedan proteger la salud mental de las personas durante una crisis y mejorar la relación entre los trabajadores y sus jefes.

3.
Disaster Med Public Health Prep ; 17: e518, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37872714

RESUMEN

OBJECTIVE: This study aimed to analyze stress, anxiety, depression, and self-efficacy levels among Spanish out-of-hospital emergency medical professionals from February 1, 2021, to April 30, 2021. METHODS: A nationwide survey was completed by 1666 Emergency Medical Services (EMS) workers. The Depression, Anxiety, and Stress Scale (DASS-21) and the General Self-Efficacy Scale (GSE) were used. Data analysis used chi-squared, análisis of variance (ANOVA), and logistic regressions. RESULTS: The sample comprised 833 (50%) men, with an average age of 44.3 ± 9.9 y (range: 19-67 y). Occupational distribution included 453 (27.2%) physicians, 474 (28.4%) nurses, and 739 (44.4%) emergency medical technicians (EMTs). EMTs exhibited higher odds of severe or extremely severe depression compared with physicians (odds ratio [OR]: 1.569; 95% confidenceinterval [95% CI]: 1.213-2.030) and nurses (OR: 1.561; 95% CI: 1.211-2.012). EMTs also displayed higher probabilities of severe or extremely severe anxiety compared with nurses (OR: 1.944; 95% CI: 1.529-2.701). Furthermore, EMTs demonstrated elevated probabilities of severe or extremely severe stress compared with physicians (OR: 1.387; 95% CI: 1.088-1.770). However, no significant differences were found in self-efficacy, with a median value of 73 [20]. CONCLUSIONS: Out-of-hospital EMS workers experienced mental health challenges, showing varying levels of depression, stress, and anxiety across different occupational groups. EMTs were particularly affected.


Asunto(s)
Servicios Médicos de Urgencia , Salud Mental , Masculino , Humanos , Adulto , Persona de Mediana Edad , Femenino , Estudios Transversales , Autoinforme , España/epidemiología
4.
Plants (Basel) ; 12(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36771723

RESUMEN

The Mi-1 gene of tomato (Solanum lycopersicum) confers resistance against some nematodes and insects, but the resistance mechanisms differ depending on the harmful organism, as a hypersensitive reaction (HR) occurs only in the case of nematodes. The gene Rme1 is required for Mi-1-mediated resistance to nematodes, aphids, and whiteflies, and several additional proteins also play a role in this resistance. Among them, the involvement of the chaperone HSP90 has been demonstrated in Mi-1-mediated resistance for aphids and nematodes, but not for whiteflies. In this work, we studied the implication of the Hsp90 gene in the Mi-1 resistance against the whitefly Bemisia tabaci by means of Tobacco rattle virus (TRV)-based virus-induced gene silencing (VIGS). The silencing of the Hsp90 gene in tomato Motelle plants carrying the Mi-1 gene resulted in a decrease in resistance to whiteflies, as oviposition values were significantly higher than those on non-silenced plants. This decrease in resistance was equivalent to that caused by the silencing of the Mi-1 gene itself. Infiltration with the control TRV vector did not alter Mi-1 mediated resistance to B. tabaci. Similar to the Mi-1 gene, silencing of Hsp90-1 occurs partially, as silenced plants showed a significant but not complete suppression of gene expression. Thus, our results demonstrate the requirement of Hsp90 in the Mi-1-mediated resistance to B. tabaci and reinforce the hypothesis of a common model for this resistance to nematodes and insects.

5.
Artículo en Inglés | MEDLINE | ID: mdl-36834266

RESUMEN

This study aimed to describe factors relating to the psychological distress of healthcare workers (HCWs) in Spanish out-of-hospital emergency medical services (EMS), according to the previous or non-use of psychotropic drugs or psychotherapy. A multicentre, cross-sectional descriptive study was designed. The study population were all physicians, nurses, and emergency medical technicians (EMTs) working in any Spanish out-of-hospital EMS between February and April 2021. The main outcomes were the levels of stress, anxiety, depression, and self-efficacy, assessed by DASS-21 and G-SES. Differences in levels of stress, anxiety, depression, and self-efficacy, according to sex, age, previous use of psychotropic drug or psychotherapy, work experience, professional category, type of work, and modification of working conditions were measured using the Student's t-test for independent samples, one-way ANOVA, Pearson's correlation, or 2-factor analysis of covariance. A total of 1636 HCWs were included, of whom one in three had severe mental disorders because of the pandemic. The interaction of the previous or non-use of psychotropic drugs or psychotherapy with the rest of the factors considered did not modify the levels of stress, anxiety, depression, and self-efficacy. However, HCWs with a history of psychotropic drug or psychotherapy use had a more intense negative emotional response and lower self-efficacy, regardless of their sex, professional category, type of work, or change in the working conditions. These HCWs are considered particularly vulnerable to the development or recurrence of new disorders or other comorbidities; therefore, the implementation of monitoring and follow-up strategies should be a priority.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Estudios Transversales , SARS-CoV-2 , Ansiedad/epidemiología , Personal de Salud/psicología , Hospitales , Depresión/epidemiología
6.
J Clin Med ; 11(8)2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35456319

RESUMEN

This study aimed to analyze the psychological affectation of health professionals (HPs) of Spanish Emergency Medical Services (EMSs) according to the cumulative incidence (CI) of COVID-19 cases in the regions in which they worked. A cross-sectional descriptive study was designed, including all HPs working in any EMS of the Spanish geography between 1 February 2021 and 30 April 2021. Their level of stress, anxiety and depression (DASS-21) and the perception of self-efficacy (G-SES) were the study's main results. A 2-factor analysis of covariance was used to determine if the CI regions of COVID-19 cases determined the psychological impact on each of the studied variables. A total of 1710 HPs were included. A third presented psychological impairment classified as severe. The interaction of CI regions with the studied variables did not influence their levels of stress, anxiety, depression or self-efficacy. Women, younger HPs or those with less EMS work experience, emergency medical technicians (EMT), workers who had to modify their working conditions or those who lived with minors or dependents suffered a greater impact from the COVID-19 pandemic in certain regions. These HPs have shown high levels of stress, anxiety, depression and medium levels of self-efficacy, with similar data in the different geographical areas. Psychological support is essential to mitigate their suffering and teach them to react to adverse events.

7.
J Clin Med ; 10(23)2021 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-34884280

RESUMEN

Health professionals (HPs), especially those working in the front line, have been one of the groups most affected by the COVID-19 pandemic. The objective of this study is to identify the best available scientific evidence on the impact of the COVID-19 pandemic on the mental health of out-of-hospital HPs in terms of stress, anxiety, depression, and self-efficacy. A living systematic review of the literature was designed, consulting the electronic online versions of the CINHAL, Cochrane Library, Cuiden, IBECS, JBI, LILACS, Medline PyscoDoc, PsycoINFO, Scopus, and Web of Science databases in November 2021. Original research was selected, published in either English, Spanish, French, Italian, or Portuguese. In total, 2082 publications were identified, of which 16 were included in this review. The mental health of out-of-hospital HPs was affected. Being a woman or having direct contact with patients showing suspicious signs of COVID-19 or confirmed cases were the factors related to a greater risk of developing high levels of stress and anxiety; in the case of depressive symptoms, it was having a clinical history of illnesses that could weaken their defenses against infection. Stopping unpleasant emotions and thoughts was the coping strategy most frequently used by these HPs.

8.
Insect Sci ; 28(4): 1121-1138, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32458593

RESUMEN

The use of genetically modified varieties tolerant to herbicides (HT varieties) and resistant to insects (Bt varieties) in combination with application of a broad-spectrum herbicide such as glyphosate could be an effective option for the simultaneous control of weeds and pests in maize. Nevertheless, the possible impact of these tools on nontarget arthropods still needs to be evaluated. In a field study in central Spain, potential changes in populations of canopy-dwelling arthropods in Bt maize under different weed management options, including glyphosate application, were investigated. Canopy-dwelling arthropods were sampled by visual inspection and yellow sticky traps. The Bt variety had no effect on any group of studied arthropods, except for the expected case of corn borers-the target pests of Bt maize. Regarding the effects of herbicide regimes, the only observed difference was a lower abundance of Cicadellidae and Mymaridae on yellow sticky traps in plots not treated with pre-emergence herbicides. This effect was especially pronounced in a treatment involving two glyphosate applications. The decrease in Cicadellidae and Mymaridae populations was associated with a higher density of weeds in plots, which may have hindered colonization of the crop by leafhoppers. These differences, however, were only significant in the last year of the study. The low likelihood of the use of glyphosate- and herbicide-tolerant varieties for weed control triggering important effects on the nontarget arthropod fauna of the maize canopy is discussed.


Asunto(s)
Artrópodos/efectos de los fármacos , Toxinas de Bacillus thuringiensis , Endotoxinas , Proteínas Hemolisinas , Herbicidas/farmacología , Zea mays , Animales , Toxinas de Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis/farmacología , Biodiversidad , Productos Agrícolas/genética , Endotoxinas/genética , Endotoxinas/farmacología , Glicina/análogos & derivados , Glicina/farmacología , Hemípteros/efectos de los fármacos , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacología , Himenópteros/efectos de los fármacos , Control de Plagas , Malezas/efectos de los fármacos , Plantas Modificadas Genéticamente , Dinámica Poblacional , Control de Malezas , Zea mays/genética , Glifosato
9.
Bull Entomol Res ; 111(1): 73-81, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32515317

RESUMEN

The permeability of the crop surroundings to pests and the landscape structure can influence pest dispersal between crop patches as well as its abundance within the crop. In this work, we analyzed the dispersal of the olive moth Prays oleae (Bernard) throughout the olive grove surroundings and their abundance within the crop following three approaches: (i) pollen grains settled on bodies of olive moths collected in olive groves were identified and compared with flora occurring on the surrounding patches; (ii) the capability of P. oleae males to penetrate non-crop patches was analyzed (iii) the effect of the landscape structure on the abundance of the three generations of the olive moth was studied. Pollen grains of scrubs and other trees occurring in the crop surroundings, such as Cistus sp., Quercus sp., Juniperus-type or Pinaceae were identified on P. oleae bodies suggesting that P. oleae penetrates into non-crop habitats. Additionally, woody and, to a lesser degree, herbaceous patches, did not constitute barriers for P. oleae. Finally, more complex and heterogeneous patches presented lower numbers of captures of P. oleae. These results give new insights into the movements of the olive moth in the olive grove surroundings and suggest that the management of non-crop areas could influence this pest abundance.


Asunto(s)
Distribución Animal , Productos Agrícolas , Ambiente , Mariposas Nocturnas/fisiología , Animales , Productos Agrícolas/crecimiento & desarrollo , Masculino , Densidad de Población , Portugal
10.
Insects ; 11(6)2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32604835

RESUMEN

The olive fruit fly (olf) Bactrocera oleae is the most damaging olive pest. The intensive use of organophosphates (OPs) to control it, led to an increase in resistance in field populations. This study assesses the presence and distribution of three mutations at the ace gene related to target site insensitivity to OPs in Spain. Samples from other Mediterranean countries were included as external references. Resistance-conferring alleles (from exons IV and VII of the ace gene) reached almost an 80% frequency in olf Spanish populations. In total, 62% of them were homozygous (RR/RR), this being more common in eastern mainland Spain. High frequencies of RR/RR individuals were also found in North Mediterranean samples. Conversely, in Tunisia, only sensitive alleles were detected. Finally, the exon X mutation ∆Q3 had an extremely low frequency in all samples. The high frequency of genotype RR/RR in Spain indicates high fitness in an agroecosystem treated with pesticides, in contrast to ∆Q3. At exon IV all flies carried the same haplotype for the allele conferring resistance. The sequence analysis at this exon suggests a unique origin and fast expansion of the resistant allele. These results provide evidence that OPs appropriate use is needed and prompt the search for alternative methods for olf pest control.

11.
Enferm Clin (Engl Ed) ; 29(3): 155-169, 2019.
Artículo en Inglés, Español | MEDLINE | ID: mdl-30529053

RESUMEN

AIM: To gain a deeper knowledge of the phenomenon of cardiopulmonary resuscitation by capturing the meanings that professionals attach to the behaviour of reanimation and its relationship with Social Cognitive Theory. METHOD: Qualitative research from a phenomenological approach focussing on field work with a focus group of professionals from Madrid (doctors, nurses and technicians), as well as a previous study. After the transcription of the data, it was coded, categories were formed and it was grouped into dimensions, interpreting the data according to the Social Cognitive Theory. Data was collected from other sources, experience of professionals and family members who had witnessed a cardiopulmonary resuscitation, until the saturation of the data. RESULTS: The phenomena that affect the people involved in a cardiopulmonary resuscitation were explored holistically. The relevant aspects to feel able to perform cardiopulmonary resuscitation, as well as those that may hinder the behaviour were identified. Two dimensions were found, personal and situational factors, as well as several categories in each dimension related to Bandura's theory of self-efficacy. CONCLUSIONS: Professionals' self-efficacy in a cardiopulmonary resuscitation does not always depend on the technical skills acquired. Personal and situational factors influence the professional being able to vary their behaviour cognitively and emotionally. This knowledge enables cardiopulmonary resuscitation competencies in a clinical situation to be improved and individualized training programmes to be designed in teaching practice.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Reanimación Cardiopulmonar , Servicio de Urgencia en Hospital , Autoeficacia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa
12.
Pest Manag Sci ; 70(3): 454-61, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23765699

RESUMEN

BACKGROUND: Monosteira unicostata is an important pest of almond tree in the Mediterranean region requiring control methods alternative to synthetic pesticides. The efficacy of kaolin, azadirachtin and potassium salts of fatty acids combined with thyme essential oil against adults and fourth instar nymphs of this tingid was evaluated in laboratory assays. RESULTS: In no choice assays with adults, kaolin significantly increased mortality compared to control (42.7% versus 23.8%) and reduced the oviposition of females (11.8 versus 35.3 eggs), the feeding activity (169.6 versus 471.2 excrements) and the damage caused (1.1 versus 2.3 damage index). In choice assays with adults, the repellence index calculated for kaolin (48.2%) was significantly higher compared to control (-15.3%), resulting in oviposition, feeding and damage deterrence indices also significantly higher than the control. In no choice assays with nymphs, all products increased mortality and reduced the feeding activity and the damage caused on leaves. Potassium soap with thyme essential oil and azadirachtin were the most effective compounds (98.0% and 97.6% mortality versus 13.3% control mortality, respectively). CONCLUSION: The products tested have shown high and different efficacy on nymphs and adults of Monosteira unicostata. This activity might be suitable for the practical application of these compounds to control its populations under real field conditions.


Asunto(s)
Hemípteros/efectos de los fármacos , Control de Insectos/métodos , Limoninas/farmacología , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Thymus (Planta)/química , Animales , Conducta Alimentaria/efectos de los fármacos , Femenino , Hemípteros/fisiología , Caolín/farmacología , Masculino , Oviposición/efectos de los fármacos
13.
Pest Manag Sci ; 69(4): 520-6, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23034882

RESUMEN

BACKGROUND: Insect growth regulators (IGRs) act specifically on arthropods. This selectivity makes them an interesting alternative to traditional insecticides for pest control. The aim of this work was to test the IGRs azadirachtin, cyromazine, flufenoxuron, lufenuron and pyriproxyfen as useful pesticides for the control of the olive fruit fly, Bactrocera oleae (Rossi), a key pest of olive crops. RESULTS: Of the products tested, the chitin-synthesis inhibitor lufenuron showed the highest efficacy. The life parameter showing the strongest effect was the egg hatch, because lufenuron caused nearly 100% egg mortality 7 days after treatment. However, sterility was not transmitted from the treated males to the untreated females. The LC50 and LC90 values for a 7 day evaluation period were 19.3 and 86.2 µg AI mL(-1) respectively. Azadirachtin, cyromazine and flufenoxuron also caused significant increases in egg mortality. However, these increases were less than those produced by lufenuron. Pyriproxyfen had a stimulatory effect on B. oleae fecundity. CONCLUSION: Applied as a bait treatment, a procedure used frequently in the field for the control of B. oleae, lufenuron is potentially useful against this important pest.


Asunto(s)
Benzamidas/toxicidad , Control de Insectos , Hormonas Juveniles/toxicidad , Tephritidae , Animales , Femenino , Fertilidad/efectos de los fármacos , Masculino
16.
Arch Bronconeumol ; 44(3): 170-2, 2008 Mar.
Artículo en Español | MEDLINE | ID: mdl-18361889

RESUMEN

Takayasu arteritis is an inflammatory disease that affects large vessels, especially the aorta and its branches. The clinical features of the disease depend on which arteries are affected. Although pulmonary artery involvement is common, only rarely is this the main clinical manifestation. We describe the case of a young woman with dyspnea who had severe pulmonary hypertension secondary to Takayasu arteritis of the pulmonary artery. She was administered corticosteroid (methylprednisolone) and immunosuppressant (azathioprine) therapy and a stent was implanted in the left pulmonary artery. Both hemodynamic and clinical signs improved.


Asunto(s)
Hipertensión Pulmonar/etiología , Arteritis de Takayasu/complicaciones , Adulto , Femenino , Humanos , Índice de Severidad de la Enfermedad
18.
Enferm Clin ; 17(3): 117-27, 2007.
Artículo en Español | MEDLINE | ID: mdl-17686413

RESUMEN

OBJECTIVE: To determine and prioritize the research competencies that should be acquired by nurses in distinct educational (graduate, masters, doctorate) and clinical practice settings (basic, intermediate and advanced) and in specialized training. METHOD: An observational, descriptive, cross sectional study was performed in 2006. The generic and specific competencies for each of the 7 above-mentioned settings were established and sent by electronic mail to a group of experts who were asked to evaluate each competency on a scale from 1 to 5 (1 = not important, 5 = very important). RESULTS: Evaluations were received from 34 (74%) of the 46 experts contacted. Of the general competencies, those receiving the highest scores, with a median of 5 points, were "ethical commitment" and "ability to work in a team". Among the specific competencies, those most highly scored were "awareness of the need to base nursing practice on the results of scientific research", "ability to critically read the scientific literature" and "ability to base nursing practice on the results of scientific research and the best available evidence". For doctorates and advanced-level nursing, most of the competencies, both general and specific, obtained a median score of 5 points. CONCLUSIONS: The most highly scored competencies were those relating to critical thinking, ethics and information analysis at each of the three levels of nursing training. Knowledge of English and interpersonal skills were less highly valued.


Asunto(s)
Competencia Clínica , Investigación en Enfermería/organización & administración , Estudios Transversales
19.
J Econ Entomol ; 98(6): 2266-71, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16539159

RESUMEN

Plant resistance to the B and Q biotypes of sweetpotato whitefly, Bemisa tabaci (Gennadius), induced by benzo [1,2,3] thiadiazole-7-carbothioic acid-S-methyl ester (BTH or acibenzolar-S-methyl) in tomato 'Marmande' plants was evaluated in free-choice and no-choice assays under different conditions. BTH is the active ingredient of the Syngenta plant activator Bion. BTH treatment affected host preference of B. tabaci (B and Q biotypes) adults on plants sprayed with Bion at 0.2 and 0.4 g/liter during the earlier days of free-choice assays. As a consequence, a decrease in the total number of eggs (although female fecundity was not affected) and in the final number of pupae and empty pupal cases was observed. The effect produced by BTH applied at 0.1 g/liter Bion was not significant. In no-choice assays, a reduction of the numbers of first-stage larvae and total individuals and a delay in insect development were observed when local treatment was restricted to one leaflet per plant, 5 d before B. tabaci (biotype B) infestation. This acquired resistance induced by BTH seemed to be locally expressed because of the differences between treated and nontreated leaflets in the same plants, whereas no differences in nontreated leaflets were observed between BTH-treated and control plants.


Asunto(s)
Hemípteros/efectos de los fármacos , Insecticidas/farmacología , Tiadiazoles/farmacología , Animales , Relación Dosis-Respuesta a Droga , Femenino , Larva , Solanum lycopersicum , Masculino , Óvulo , Pupa , Temperatura , Factores de Tiempo
20.
Mycopathologia ; 156(2): 93-100, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12733630

RESUMEN

Growth of the biocontrol fungus Epicoccum nigrum was more sensitive to ionic solute water stress (NaCl) than non-ionic (glycerol) on potato dextrose-based media at -0.5, -3.0 and -5.5 MPa water potentials. Subsequent physiological manipulation of growth of E. nigrum in glycerol-modified media to -3.0 MPa water potential resulted in a significant increase in the accumulation of compatible solutes in both mycelial liquid cultures and spores, but no enhanced accumulation of the desiccation protectant trehalose, when compared to unmodified media (-0.5 MPa). The main solute accumulated was glycerol, followed by arabitol. In temporal studies over 20 days maximum accumulation of glycerol occurred in 5-d old cultures with water stressed cultures having 250x greater amounts than those from unmodified medium. The arabitol content was also higher in mycelium and spores produced under water stress. The difference was maximum after 15 days growth. Glucose content decreased over time in mycelial colonies but increased in spores. The germination of conidia from the two treatments was similar, regardless of compatible solute content, even at -9.25 MPa water potential stress. However, germ tube extension was significantly increased at this water potential level. The production of E. nigrum spores at -3.0 MPa water potential resulted in improved survival when stored fresh at 4 and 25 degrees C. However, freeze-drying severely affected the viability of spores produced on both media (-0.5 or 3.0 MPa). Accumulation of compatible solutes may assist the fungus in better ecological competence and establishment in the phyllosphere, where water availability is often limited.


Asunto(s)
Ascomicetos/crecimiento & desarrollo , Control Biológico de Vectores/métodos , Agua/metabolismo , Ascomicetos/metabolismo , Ecosistema , Glucosa/metabolismo , Glicerol/metabolismo , Micelio/metabolismo , Cloruro de Sodio/metabolismo , Esporas Fúngicas/metabolismo , Alcoholes del Azúcar/metabolismo
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