73 research outputs found

    No-choice ovipositional nonpreference of Bemisia tabaci (Gennadius) B biotype on tomato genotypes

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    O Brasil é um dos maiores produtores mundiais de tomate, porém grande parte da produção é perdida devido ao ataque de Bemisia tabaci (Gennadius) biótipo B. Entre as táticas de controle dessa praga num manejo integrado de pragas, pode-se relacionar a resistência de plantas. Avaliou-se a preferência para oviposição de B. tabaci biótipo B por 18 genótipos de tomateiro com diferentes densidades e tipos de tricomas utilizando-se dois métodos e estudou-se a influência dos tricomas nesta preferência, utilizando-se dois métodos para os experimentos de confinamento. Folíolos seccionados do terço superior dos tomateiros (primeiro método) e plantas com 30 dias de idade (segundo método) foram infestados com moscas-brancas durante 24 h. Para o primeiro experimento, foram realizados testes de correlação linear simples entre o número de insetos e de ovos e o número de tricomas nos tomateiros. O primeiro método foi melhor que o segundo, pois foi mais fácil de ser conduzido e demandou menos tempo para as avaliações, além disso, foi efetivo em discriminar o nível de resistência dos genótipos avaliados. Tricomas glandulares correlacionaram-se negativamente com adultos atraídos e com ovos, e positivamente com adultos capturados. Correlações negativas ocorreram entre o número de tricomas não-glandulares e o número de insetos capturados, e entre o número de tricomas totais e o número de insetos atraídos e capturados. Correlações positivas ocorreram entre o número de tricomas totais e o número de ovos cm-2 e de tricomas não-glandulares e o número de ovos. Ambos os métodos foram eficientes para discriminar os genótipos, principalmente os resistentes, com destaque para LA716, PI134417 e PI134418, que apresentaram altíssima antixenose para oviposição relacionada à presença de tricomas glandulares tipo IV. A preferência para oviposição de B. tabaci pelos genótipos LA1963 e NAV1062 está relacionada à alta densidade de tricomas não-glandulares tipo V.Brazil is one of the main tomato producers worldwide. Nevertheless, 40 to 70% of the production is lost due to Bemisia tabaci (Gennadius) B biotype attacks. Resistant plant germplasm can be an important method for controlling this pest in an integrated pest management program. This research aimed to evaluate the no-choice ovipositional preference of B. tabaci B biotype on 18 tomato genotypes with different densities and types of trichomes testing two screening techniques and to determine the influence of trichomes on whitefly ovipositional preference. Two methods of confinement experiments were used. Leaflets detached from the upper third part of the tomato plants (first experiment) and 30-day-old plants (second experiment) were infested with whiteflies during 24 h. For the first experiment, simple linear correlation tests between the number of insects and eggs, and number of trichomes in the tomato genotypes were carried out. The first technique was better than the second one, as it was easier to carry out and the evaluation demanded less time and as well as was effective to discriminate the resistance level of the evaluated genotypes. Glandular trichomes had a negative correlation with attracted adults and number of eggs deposited, and a positive correlation with number of trapped insects. Negative correlations were observed between number of nonglandular trichomes and trapped insects, and also between total number of trichomes and attracted and trapped insects. Positive correlations were observed between number of total trichomes and eggs cm-2 and nonglandular trichomes and number of eggs. Both confinement methods efficiently discriminated whitefly oviposition among genotypes, especially the resistant ones. High levels of antixenosis for oviposition related to type IV glandular trichomes were exhibited by genotypes LA716, PI134417 and PI134418. The high level of ovipositional preference by B. tabaci for genotypes LA1963 and NAV1062 was related to a high density of type V nonglandular trichomes

    Biological aspects of Bemisia tabaci (Genn.) B biotype (Hemiptera: Aleyrodidae) on six bean genotypes

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    A mosca-branca é um dos insetos mais prejudiciais à cultura do feijoeiro, devido principalmente à intensa sucção de seiva e à transmissão do vírus do mosaico dourado. O uso de cultivares resistentes ao inseto é uma ferramenta importante no seu controle. Ensaios foram conduzidos em laboratório, avaliando-se aspectos biológicos de Bemisia tabaci biótipo B para os seguintes genótipos de feijoeiro: Arc 3s, Arc 5s, G13028, G11056, Arc 1 e Porrillo 70. As plantas (estágio IV-1) foram infestadas por moscas-brancas durante um dia e os ovos e ninfas foram observados até a emergência dos adultos. A longevidade e a fecundidade dos insetos emergidos também foram avaliadas. Ninfas alimentadas no genótipo Arc 3s (26,5 dias) tiveram o período de desenvolvimento mais longo, seguidas de G11056 (25,9 dias) e G13028 (25,3 dias). Houve um alongamento de 5,5 dias no período de desenvolvimento dos insetos em Arc 3s quando comparado com Porrillo 70. Altas taxas de mortalidade das ninfas nos genótipos Arc 3s e G11056 (94,7 e 83,1%, respectivamente) indicam que tais materiais podem apresentar resistência do tipo não-preferência para alimentação e/ou antibiose. Assim, embora a longevidade e a fecundidade do inseto não tenham sido afetadas quando criado nos genótipos resistentes (Arc 3s, G11056, G13028 e Arc 5s), sugere-se que tais materiais sejam utilizados em programas de melhoramento de feijoeiro visando à resistência a B. tabaci biótipo B.The silverleaf whitefly is one of the most harmful pests that attack bean crops, mainly for extracting large quantities of phloem sap and transmitting the bean golden mosaic virus. Resistant germoplasm plants can be an important method for controlling this pest. The biological aspects of Bemisia tabaci B biotype on bean (Phaseolus vulgaris) genotypes were evaluated. The tests were conducted under laboratory conditions, with the following genotypes: Arc 1, Arc 3s, Arc 5s, G13028, G11056 and Porrillo 70. The bean plants in a stage IV-1 were infested during one day with silverleaf whiteflies. Afterwards the eggs and nymphs were observed until adult emergence. Longevity and fecundity of emerged insects were also evaluated. The longest development time occurred for nymphs fed on Arc 3s genotype (26.5 days), following by G11056 (25.9 days) and G13028 (25.3 days). The development period was 5.5 days longer in Arc 3s when compared with Porrillo 70. Also, the wild genotypes Arc 3s and G11056 showed higher mortality rates (94.7% and 83.1%, respectively), which may suggest antibiosis and/or feeding nonpreference resistance type. For this reason, although longevity and fecundity were not influenced when the whitefly fed on resistant genotypes (Arc 3s, G11056, G13028 and Arc 5s), those genotypes can be used for bean breeding program towards B. tabaci B biotype

    Biology of Bemisia tabaci (Genn.) B biotype (Hemiptera, Aleyrodidae) on tomato genotypes

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    O Brasil é um dos maiores produtores mundiais de tomate (Solanum lycopersicum), porém grande parte da produção é perdida devido ao ataque de Bemisia tabaci (Genn.) biótipo B. Entre as táticas de controle dessa praga num manejo integrado de pragas, pode-se relacionar a resistência de plantas. Ensaios para avaliar alguns aspectos biológicos de B. tabaci foram realizados com 18 genótipos de tomateiro, em condições controladas de laboratório (casa de vegetação). Plantas com 30 dias de idade foram colocadas em gaiolas plásticas e infestadas com 20 casais de moscas-brancas cada, durante 24h. Acompanhou-se então o desenvolvimento de pelo menos 30 ovos em três folíolos por planta (repetição) até a emergência dos insetos. Os insetos criados nos genótipos LA1335, PI365928 e LA722 apresentaram prolongamento de três dias no período de desenvolvimento, em relação aos criados em PI134418 (20,3 dias). As maiores taxas de mortalidade das ninfas de mosca-branca ocorreram nos genótipos PI365928, LA1335 e LA722 (63,8, 54,5 e 53,3%, respectivamente) e as menores, nos genótipos IAC294 e IAC68F-22-2 (4,9 e 6,2%, respectivamente). Os genótipos LA1335, PI365928 e LA722 apresentam resistência moderada do tipo não-preferência para alimentação e/ou antibiose a B. tabaci biótipo B.Brazil is one of the main tomato (Solanum lycopersicum) producers worldwide. Nevertheless, considerable part of the production is lost due to Bemisia tabaci (Genn.) B biotype attacks. Resistant plants can be an important method for controlling this pest in an integrated pest management. Tests for evaluating some biological aspects of B. tabaci were carried out on 18 tomato genotypes, in controlled laboratory greenhouse conditions. Thirty-day-old plants placed in plastic cages were infested with 20 whitefly pairs each, for 24 h. The development of at least 30 eggs in three leaflets per plant (repetition) was observed until adult emergence. The development period of insects grown in LA1335, PI365928 and LA722 genotypes took three days longer when compared to the ones grown in PI134418 (20.3 days). The highest mortality rate of whitefly nymphs occurred in PI365928, LA1335 and LA722 genotypes (63.8, 54.5 and 53.3%, respectively), and the smallest ones in IAC294 and IAC68F-22-2 genotypes (4.9 e 6.2%, respectively). LA1335, PI365928 and LA722 genotypes presented moderate feeding nonpreference and/or antibiosis-based resistance to B. tabaci B biotype

    Survey of sheep antibodies of smooth and rough strains of brucella in the north patagonic area of La Pampa

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    Brucellosis is an infectious disease that affects domestic animals, producing heavily losses through abortions, and infertility in rams.The flock epidemiology situation in the north Patagonic area of Argentina (La Pampa) to the present disease is unknown; consequently the objective was to determine the prevalence of the disease. Out of 10.000 sheep, there were sampled 1.800 animals according to the application of the minimum sample size for estimating a rate with specified degree of precision in the Departments of Mara-co, Chapaleufu, Realico, Rancul, Conhelo and Quemu-Quemu representing an area of 22.072 km2, in the frame of reintroduction of sheep production in the province. Independently of the number of sheep per farm, 20- 30% of the flock was sampled, that represent 15% (270) rams and 85% (1.530) ewes. After collecting serum from jugular blood, the samples were analysed either for the presence of antibodies against smooth strain through Buffer Plate Agglutination Test (BPA); or antibodies against rough strain of brucella through Agar Gel Immuno-diffusion Test (AGID). Bewilderment of all the animals was negative to both tests. Despite brucellosis is a high prevalent infectious di-sease in other part of the country, these results emphasise the condition of free areas of the disease

    Reducing COD level on oily effluent by utilizing biosurfactant-producing bacteria

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    Two bacteria isolated from crude oil contaminated soil, Pantoea agglomerans and Planococcus citreus, produced biosurfactants utilizing 1.5% of kerosene and olive oil as the sole carbon sources, respectively. The bacteria and the biosurfactants produced were introduced to oily effluent, arising from margarine and soap industry. Emulsification activities were determined by increases in the absorbance of the oil-in-water emulsions at 610 nm, whereas the water-in-oil emulsions were expressed as the height (cm) of the emulsion layers formed. The 72 h incubation experiment resulted in a COD (Chemical Oxygen Demand) reduction of 76% with Planococcus citreus strain and 70% with Pantoea agglomerans.The COD reduction with bacterial biosurfactants was over 50% in 24 h of incubation. The COD reduction showed that these strains and the surfactants produced could be used in bioremediation processes.Duas bactérias isoladas de solo contaminado com derivados de petróleo, Pantoea agglomerans e Planococcus citreus, produzem biosurfactantes utilizando respectivamente 1.5% de querosene e óleo de oliva como únicas fontes de carbono. As bactérias e os biosurfactantes produzidos foram adicionados a um efluente oleoso obtido de uma indústria nacional de sabão e margarina. As atividades de emulsificação foram determinadas pelo aumento da absorbância das emulsões óleo em água a 610 nm, enquanto que as emulsões do tipo água em óleo foram expressas em centímetros, pela altura do halo de espumas formado. A redução da demanda química de oxigênio (COD) mostra que as linhagens e os biosurfactantes produzidos podem ser utilizados em processos de biorremediação.10371042Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    The impact of COVID-19 lockdown and of the following "re-opening" period on specific and general psychopathology in people with Eating Disorders: the emergent role of internalizing symptoms

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    BACKGROUND: We assessed the impact of the coronavirus disease 2019 (COVID-19) pandemic on specific Eating Disorder (ED) and general psychopathology in people with an ED diagnosis during the lockdown period and after the end of the related containment measures.METHODS: People with clinically defined diagnosis and undergoing treatment for an ED completed an online survey, which included adapted questions from standardized psychometric scales. Data relative to three different time periods (before, during and after the end of lockdown) were collected. Psychopathological changes over these periods were investigated and compared through one-way analysis of variance or covariance with repeated measures.RESULTS: Three hundred twelve people completed the survey (57.4% diagnosed with Anorexia Nervosa (AN) or atypical AN, 20.2% with Bulimia Nervosa, 15.4% with Binge Eating Disorder, 7.05% with Other Specified Feeding or Eating Disorders). The severity of both specific and general psychopathology increased during the lockdown and the rise of general symptoms persisted in the following re-opening phase, except for suicide ideation. Almost all of these findings were not affected by ED diagnosis, participants' age and illness duration.LIMITATIONS: The retrospective nature of data collection is the main limitation of the study.CONCLUSIONS: People with EDs showed a COVID-19 emergency-induced worsening of both general and specific psychopathology. The effect on general psychopathology persisted in the re-opening period. These findings suggest a high stress vulnerability of ED individuals with important effects on internalizing symptoms, which are worth of attention by clinicians

    Predicting needlestick and sharps injuries in nursing students: Development of the SNNIP scale

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    © 2020 The Authors. Nursing Open published by John Wiley & Sons Ltd. Aim: To develop an instrument to investigate knowledge and predictive factors of needlestick and sharps injuries (NSIs) in nursing students during clinical placements. Design: Instrument development and cross-sectional study for psychometric testing. Methods: A self-administered instrument including demographic data, injury epidemiology and predictive factors of NSIs was developed between October 2018–January 2019. Content validity was assessed by a panel of experts. The instrument's factor structure and discriminant validity were explored using principal components analysis. The STROBE guidelines were followed. Results: Evidence of content validity was found (S-CVI 0.75; I-CVI 0.50–1.00). A three-factor structure was shown by exploratory factor analysis. Of the 238 participants, 39% had been injured at least once, of which 67.3% in the second year. Higher perceptions of “personal exposure” (4.06, SD 3.78) were reported by third-year students. Higher scores for “perceived benefits” of preventive behaviours (13.6, SD 1.46) were reported by second-year students

    Knowledge, experiences, and attitudes toward Mantoux test among medical and health professional students in Italy: A cross-sectional study

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    BACKGROUND: The World Health Organization's Action Framework for tuberculosis elimination in low-tuberculosis incidence countries includes the screening for active and latent tuberculosis in selected high-risk groups, including health care workers. In this context, medical and health profession students, exposed to nosocomial tuberculosis transmission during training and clinical rotations, are target populations for tuberculosis screening. No updated data are available on tuberculosis screening practice and knowledge of medical and health profession students in Italy. METHODS: Within the activities Italian Study Group on Hospital Hygiene of the Italian Society of Hygiene, Preventive Medicine and Public Health, we carried out a multicentre cross-sectional study to assess knowledge, attitude and practices on tuberculosis prevention and control among Medical, Dentistry, Nursing and other health professions' students. Students were enrolled in the study on a voluntary basis and were administered a previously piloted structured questionnaire. Logistic regression models were applied to explore knowledge on tuberculosis prevention by selected socio-demographic variables and University-based tuberculosis prevention practice. RESULTS: Students of seventeen Universities across Italy participated in the study, and 58.2% of them received compulsory tuberculin skin test either at enrollment or while attending clinical practice. A total of 5,209 students filled the questionnaire. 37.7% were medicine and dentistry students (Group 1), 44.9% were nursing students (Group 2) and 17.4% were other health professions' students (Group 3). Age and gender had different distributions by groups, as well as knowledge and practice on tuberculin skin test. 84.4% of the study population (95% CI = 83.3-85.3) was aware of the existence of the tuberculin skin test, 74.4% (95% CI = 73.2-75.6) knew what is the first-level screening test for latent tuberculosis and only 22.5% (95% CI = 21.4-23.6) knew how to proceed after a positive tuberculin skin test result. Overall, knowledge on tuberculosis prevention was higher in Group 2 and lower Group 3, as compared to Group 1. CONCLUSION: In Italy, the knowledge on tuberculosis screening among University students is generally good. To reduce some of the criticalities found among the different study courses, it would be appropriate to harmonize both the regulations on tuberculosis screening practices for admission to University courses, and the educational activities on the topic of tuberculosis, to be extended to all workers involved in health care setting
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