72 research outputs found

    Resistência a Septoria lycopersici em espécies de Solanum (Secção Lycopersicon) e em progênies de S. lycopersicum × S. peruvianum

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    Septoria leaf spot (Septoria lycopersici) is one of the major fungal diseases of tomatoes (Solanum lycopersicum) in tropical and subtropical regions with humid climates and/or in areas cultivated under sprinkler irrigation systems. Sources of resistance have been found in accessions of Solanum (section Lycopersicon) species. However, many of the described sources are not effective under Brazilian conditions. The objective of this work was to evaluate wild and cultivated Solanum (section Lycopersicon) germplasm to S. lycopersici isolates. A collection of 124 accessions was initially evaluated under greenhouse conditions. Ten accessions were highly resistance (HR), whereas 33 were classified as having a resistant (R) response to S. lycopersici isolates. Field evaluation was also conducted with a sub-set of accessions identified as either HR or R in the greenhouse experiment. This field evaluation confirmed greenhouse tests and indicated the presence of some potential sources of rate-reducing resistance. One highly resistant and eight resistant S. habrochaites accessions were identified as being resistant under both conditions, confirming that this wild species is one of the most promising sources of resistance to S. lycopersici. Five new sources with high levels of resistance were found in S. peruvianum accessions (PI-306811, CNPH-1036, LA-1910, LA-1984 and LA-2744). One accession derived from an interspecific cross between S. lycopersicum and S. peruvianum was also found to be highly resistant and might be useful to introgress resistance factors from this wild species into cultivated tomato germplasm. However, additional breeding efforts will be necessary to introgress into the cultivated tomato the resistance factors identified in other S. peruvianum accessions due to the presence of natural crossing barriers between the two species.A mancha-de-septória (Septoria lycopersici) é importante doença fúngica do tomateiro (Solanum lycopersicum) em áreas tropicais e subtropicais com alta umidade ou quando esta hortaliça é cultivada sob irrigação por aspersão. Fontes de resistência têm sido encontradas em germoplasma de Solanum (secção Lycopersicon). No entanto, muitas das fontes descritas não funcionam nas condições brasileiras. Avaliou-se uma coleção de germoplasma de tomate cultivado e selvagem (Solanum secção Lycopersicon) visando identificar novas fontes de elevada resistência. Uma coleção de 124 acessos foi inicialmente avaliada sob condições de casa de vegetação. Somente dez acessos foram classificados como altamente resistentes e 33 foram classificados como resistentes. Um ensaio de campo foi também conduzido com um subconjunto de acessos promissores identificados no primeiro experimento. Foi confirmada a resposta da maioria dos acessos avaliados em casa de vegetação e indicou a presença de fontes de resistência capazes de reduzir a taxa de progresso da doença. Um acesso de S. habrochaites com elevada resistência e oito acessos resistentes foram identificados, confirmando que esta espécie representa uma das mais promissoras fontes de genes de resistência a S. lycopersici. Cinco novas fontes com elevados níveis de resistência foram identificadas em acessos da espécie S. peruvianum (PI-306811, CNPH-1036, LA-1910, LA-1984 e LA-2744). Um acesso, derivado de cruzamento interespecífico entre S. lycopersicum e S. peruvianum também mostrou-se altamente resistente e poderá ser útil na introgressão deste(s) gene(s) em germoplasma de tomateiro cultivado. No entanto, esforços adicionais de melhoramento serão necessários para transferir para o tomateiro cultivado os fatores de resistência identificados em outros acessos de S. peruvianum, uma vez que existem barreiras naturais de cruzamentos entre estas duas espécies

    Didymella bryoniae resistance to fungicides in Brazil

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    O crestamento gomoso do caule (Didymella bryoniae) é uma das mais importantes doenças da melancia (Citrullus lanatus) no mundo. O controle químico, embora amplamente adotado, nem sempre pode impedir o progresso da doença no campo. A resistência do agente causal a alguns ingredientes ativos foi relatada na Europa, Japão e nos Estados Unidos, porém nenhum estudo foi feito no Brasil. Este trabalho descreve os resultados de três ensaios in vitro para resistência a fungicidas, medida pela taxa de crescimento micelial. No primeiro ensaio, sete isolados foram submetidos a nove fungicidas na metade da dose comercial recomendada. Evidência de resistência a Tiofanato metílico (TM), Carbendazim (CARB) (benzimidazóis) bem como a mistura Tiofanato metílico + Clorotalonil (TM + CHLO) foi detectada. Nenhuma resistência foi detectada contra Mancozebe, Difenoconazole, Tebuconazole e as misturas Mancozebe + Difenoconazole ou Trifloxistrobina + Propiconazole. O teste foi repetido com os mesmos sete isolados de D. bryoniae contra TM, CARB, TM + CHLO e Oxicloreto de Cobre a ¼, ½, 1 e 2 vezes a dose recomendada. Apenas Oxicloreto de cobre diminuiu consistentemente a taxa de crescimento micelial com o aumento da dose. TM não teve efeito na taxa de crescimento micelial em nenhuma concentração testada, e CARB e TM + CHLO mostraram mínimo efeito com o aumento da concentração do produto. Finalmente, 31 isolados de sete estados brasileiros foram testados para resistência a Tiofanato metílico na dose recomendada (490 ppm). Oitenta e um porcento dos isolados mostraram-se altamente resistentes. Isolados resistentes e sensíveis foram encontrados em uma mesma região geográfica. Considerando a prevalência de isolados resistentes a ambos TM e CARB, uma evidência de resistência cruzada, o uso de benzimidazoles não deve ser recomendado no controle do crestamento gomoso do caule. _________________________________________________________________________________ ABSTRACTGummy stem blight (Didymella bryoniae) is one of the most important diseases of watermelon (Citrullus lanatus) wordwide. Chemical control, although widely adopted, cannot always avoid disease progress in the field. Resistance of the causal agent to some active ingredients has been reported in Europe, Japan and in the United States, but no such study has been done in Brazil. This work reports results of three in vitro assays for fungicide resistance, as measured by the rate of mycelial growth. In the first test, seven isolates were evaluated against nine fungicides at half the recommended commercial doses. Evidence of resistance to Methyl Thiophanate (TM) and Carbendazim (CARB) (Benzimidazoles) as well as to the mixture of Methyl-Thiophanate and Chlorotalonil (TM+CHLO) was detected. No resistance was suggested to Mancozeb, Difenoconazole, Tebuconazole and the mixtures Mancozeb + Difenoconazole or Trifloxistrobine + Propiconazole. The test was repeated with the same seven isolates of D. bryoniae against TM, CARB, TM+CHLO and Copper Oxichlorate at ¼, ½, 1 and 2 times the recommended doses. Only Copper Oxichlorate consistently caused a decrease in the mycelial growth rates with increasing doses. TM had no effect on the mycelial growth rates at any of the concentrations tested, and CARB and TM+CHLO showed very minor effects with increasing product concentrations. Finally, a collection of 31 isolates from seven Brazilian states was tested for resistance against TM at the recommended dose (490 ppm). Eighty-one per cent of the isolates, from most Brazilian states, proved to be highly resistant. Resistant and sensitive isolates were found in the same geographic regions. Considering the prevalence of isolates resistant to both TM and CARB, an evidence of cross-resistance, the use of benzimidazoles should be avoided for gummy stem blight control

    FREQUENCY OF HEPATIC STEATOSIS IN A RADIOLOGY CLINIC IN PALMAS

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    ABSTRACT Introduction: Recent studies suggest that hepatic steatosis is a worldwide distribution pathology that can progress to chronic liver disease with a highly unfavorable outcome resulting in the need for liver transplantation. That’s why early diagnosis is important. The liver biopsy’s considered a "gold standard" in its diagnosis, but the use of ultrasonography helps to detect steatosis in a non-invasive manner and is a very accessible method for the population. Objectives: To evaluate the frequency of steatosis in patients treated at a radiological clinic in Palmas using abdominal ultrasonography; observing its distribution in genders and age groups and its difference between 2010 and 2016. Methods: It was used ultrasound reports of abdomen of 3.222 patients made in 2010 and of 2.346 patients made in 2016. A longitudinal analysis was performed, between these two years, regarding the frequency of hepatic steatosis at the people and also between the genders and the age groups. Results: In 2010, 25,67% of people had hepatic steatosis in the ultrasound report, while in 2016 were 31,67%. In 2010, of the total number of people with steatosis, 52,48% were women and 47,52% were men; however in 2016, 51,94% were women and 48,06% were men. Regarding the age groups, in both periods, as in men and in women, steatosis was lower at the extremes of age and more frequent around the 5th to 7th decades of life. Discussion: The frequency of hepatic steatosis has increased in the period from 2010 to 2016. It was, as seen in the literature, quite high in the 5th and 6th decades of life, besides being more frequent in females. Unlike 2010, in 2016 begins to have children under 20 with signs of steatosis. Conclusion: In the year 2010 the frequency of hepatic steatosis was 25,67%, whereas in 2016 it was 31,84%.   Keywords: Steatosis; ultrasonography; liver.Introduction: Recent studies suggest that hepatic steatosis is a worldwide distribution pathology that can progress to chronic liver disease with a highly unfavorable outcome resulting in the need for liver transplantation. That’s why early diagnosis is important. The liver biopsy’s considered a "gold standard" in its diagnosis, but the use of ultrasonography helps to detect steatosis in a non-invasive manner and is a very accessible method for the population. Objectives: To evaluate the frequency of steatosis in patients treated at a radiological clinic in Palmas using abdominal ultrasonography; observing its distribution in genders and age groups and its difference between 2010 and 2016. Methods: It was used ultrasound reports of abdomen of 3.222 patients made in 2010 and of 2.346 patients made in 2016. A longitudinal analysis was performed, between these two years, regarding the frequency of hepatic steatosis at the people and also between the genders and the age groups. Results: In 2010, 25,67% of people had hepatic steatosis in the ultrasound report, while in 2016 were 31,67%. In 2010, of the total number of people with steatosis, 52,48% were women and 47,52% were men; however in 2016, 51,94% were women and 48,06% were men. Regarding the age groups, in both periods, as in men and in women, steatosis was lower at the extremes of age and more frequent around the 5th to 7th decades of life. Discussion: The frequency of hepatic steatosis has increased in the period from 2010 to 2016. It was, as seen in the literature, quite high in the 5th and 6th decades of life, besides being more frequent in females. Unlike 2010, in 2016 begins to have children under 20 with signs of steatosis. Conclusion: In the year 2010 the frequency of hepatic steatosis was 25,67%, whereas in 2016 it was 31,84%

    Search for sources of resistance to Fusarium wilt (Fusarium oxysporum f. sp. vasinfectum) in okra germplasm

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    – Fusarium oxysporum f. sp. vasinfectum (FOV) is one the most destructive okra (Abelmoschus esculentus) pathogens in Brazil. Fifty-four okra accessions were evaluated for resistance to FOV. Greenhouse screening was initially carried out with one FOV isolate (‘Fus-194’). Inoculation (in all assays) was carried out with 21-day-old plantlets, using the root-dipping inoculation technique. Thirty-three accessions displaying differential responses in the first screening were re-evaluated in two additional assays, using two FOV isolates (‘Fus-194’ and ‘Fus-201’). Twelve accessions were rated as highly to intermediately resistant to ‘Fus-194’ during the dry/moderate temperature season, whereas nine accessions were classified as highly to intermediately resistant to ‘Fus-201’. In the assay carried out in the wet and warm season, 72% of the accessions were classified as having high and intermediate resistance to ‘Fus-194’, and 32% were resistant to ‘Fus-201’. The accessions ‘Santa Cruz-47’, ‘BR-2399’ and ‘BR-1449’ were the most promising resistance sources

    AS INFLUÊNCIAS DAS DIFERENTES CORRENTES HISTORIOGRÁFICAS E DO LIVRO DIDÁTICO NAS PRÁTICAS DE ENSINO DE HISTÓRIA – UMA AMOSTRAGEM DA HISTÓRIA ENSINADA NO COTIDIANO ESCOLAR

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    A presente pesquisa tem como objetivo evidenciar a produção de saber histórico escolar, analisando como os docentes trazem para a sua prática as diferentes correntes historiográficas. Realizamos uma investigação no cotidiano do trabalho dos docentes de História em três unidades de ensino, e, a partir da análise dessas amostragens, concluímos que os professores utilizam de determinadas astúcias e táticas individuais para apropriação apenas parcial de teorias curriculares e historiográficas. Se não há uma completa recusa de tais teorias, a pesquisa demonstra, entretanto, ocorre a apropriação somente daquilo que lhes interessa na realização de sua prática educativa

    Yield, bolting and leaf blight in carrots grown under organic and conventional conditions

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    Quatro ensaios foram implantados no verão para avaliar a produtividade, o florescimento prematuro e a queima-das-folhas em genótipos de cenoura conduzidos em sistema orgânico e convencional. Os ensaios foram instalados em Brazlândia e na Embrapa Hortaliças. O delineamento experimental foi de blocos ao acaso, com oito tratamentos (genótipos Alvorada, Brasília RL, Brasília Bionatur, Kuronan, Nantes 3 Tip Top, Carandaí AG 106, Brazlândia e Pop. 0212246) e cinco repetições. Os nutrientes foram incorporados ao solo através de composto orgânico, no sistema orgânico e, fertilizantes químicos, no sistema convencional. Aos 70 dias da semeadura as plantas foram avaliadas no campo para incidência de doenças. Foi também identificada a prevalência de patógenos. A colheita foi realizada 95 dias após a semeadura. O florescimento prematuro foi mais freqüente no genótipo Brasília Bionatur, no sistema convencional, em Brazlândia. Foi observada diferença entre genótipos para queima-das-folhas nos dois sistemas. Nantes foi a mais suscetível, enquanto a Pop. 0212246 foi uma das mais resistentes nos dois sistemas de cultivo. Alternaria dauci prevaleceu em Brazlândia, enquanto Cercospora carotae foi observado em ambas as localidades, no sistema orgânico. Quanto à produção comercial e total os genótipos Pop. 0212246 e Brazlândia estiveram entre os mais produtivos, independente do sistema de cultivo. Para produtividade comercial e total, número e peso de raízes refugadas o sistema convencional apresentou resultados superiores ao orgânico. As cultivares Brasília RL, Brazlândia e a Pop. 0212246 podem ser recomendadas para plantio no período de verão, no DF, independente do sistema de cultivo. A Pop. 0212246 apresenta características agronômicas desejadas pelo mercado e poderá futuramente ser disponibilizada para produtores da região. ____________________________________________________________________________________ ABSTRACTFour experiments were carried out with carrots genotypes during summer season in Distrito Federal, Brazil, to evaluate yield, bolting and leaf blight under organic and conventional conditions. The experiments were carried out in two locations and in each one two experiments were established, considering both crop systems. The experimental design was a random block with eight treatments and five replicates. The treatments consisted of the cvs. Alvorada, Brasília RL, Brasília Bionatur, Kuronan, Nantes 3 Tip Top, Carandaí AG 106, Brazlândia and Pop. 0212246. The soil was fertilized with organic compost for the organic trial and with chemical fertilizer for the conventional trial. Plants were evaluated for leaf blight incidence, 70 days after sowing date, through visual observation. Roots were harvested 95 days after sowing, washed, classified and weighted. Bolting was more frequent in Brasília Bionatur, under conventional condition, in Brazlândia. A difference of susceptibility to leaf blight among genotypes was observed in plants cultivated in the organic system. Nantes was the most susceptible while Pop. 0212246 was the most resistant. Alternaria dauci was observed more frequently at Brazlândia, while Cercospora carotae was observed at both locations, similarly, under organic conditions. For commercial and total yield, commercial and total root number, Pop. 0212246 and Brazlândia were the best materials in both crop systems. Total and commercial yield, total and commercial root number, number and weight of refused roots were higher in the conventional area, compared to the organic area. Brasília and Brazlândia can be recommended for Distrito Federal, independently of crop system, during summer season. Pop. 0212246 showed desirable agronomical characteristics and can be, in the future, available for farmers in Distrito Federal

    Mating type, mefenoxam sensitivity, and pathotype diversity in Phytophthora infestans isolates from tomato in Brazil

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    O objetivo deste trabalho foi caracterizar 79 isolados de Phytophthora infestans, coletados em campos de tomate (Solanum lycopersicum), quanto ao grupo de compatibilidade, à sensibilidade ao mefenoxan, e à diversidade de patótipos. Os isolados foram obtidos em coletas realizadas nos anos de 2006 e 2007, em sete Estados do Brasil e no Distrito Federal. Os isolados foram usados para determinação do grupo de compatibilidade sexual (n=79), resistência ao fungicida mefenoxam (n=79) e espectro de virulência aos genes de efeito principal Ph-1, Ph-2 e Ph-3/Ph-4 (n=62). Todos os isolados foram classificados no grupo de compatibilidade A1. Isolados insensíveis ao fungicida mefenoxam foram detectados em todos os Estados amostrados, e apresentaram frequência média superior a 50%. Não houve diferença de diversidade de patótipos entre as subpopulações coletadas em 2006 e 2007, e nem entre os isolados agrupados como resistentes ou intermediariamente sensíveis ao mefenoxam. Os genes de resistência foram suplantados em diferentes frequências: Ph-1, 88,7%; Ph-2, 64,5%; e Ph-3/Ph-4, 25,8%. Isolados complexos capazes de suplantar a resistência dos quatro genes de resistência foram encontrados em baixa frequência. Programas de melhoramento de tomate no Brasil devem evitar o desenvolvimento de cultivares com resistência baseada exclusivamente em genes de efeito principal.The objective of this work was to characterize 79 Phytophthora infestans isolates collected in tomato (Solanum lycopersicum) fields, as to mating type, mefenoxam sensitivity, and pathotype composition. The isolates were sampled in 2006 and 2007 in seven Brazilian states as well as in the Distrito Federal. They were characterised as to mating type (n=79), sensitivity to fungicide mefenoxam (n=79), and virulence to three major resistance genes Ph-1, Ph-2, and Ph-3/Ph-4 (n=62). All isolates were of the mating type A1. Resistant isolates were detected in all sampled states, and its average frequency was superior to 50%. No difference was detected in pathotype diversity, neither between subpopulations collected in 2006 and 2007 nor between isolates grouped as resistant or intermediately sensitive to mefenoxam. All major resistance genes were overcome at different frequencies: Ph-1, 88.7%; Ph-2, 64.5%; and Ph-3/Ph-4, 25.8%. Isolates with virulence genes able to overcome all major resistance genes were detected at low frequencies. Tomato breeding programs in Brazil must avoid the development of cultivars with resistance based exclusively on major genes

    Pré-fragilidade e fragilidade de idosos residentes em município com baixo Índice de Desenvolvimento Humano

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    OBJECTIVE: to identify the prevalence of the factors associated with pre-frailty and frailty of elderly residents in a municipality with a low Human Development Index METHOD: Cross-sectional study with a populational and household framework conducted with 316 elderly people. Frailty was determined from the presence of three or more of the following factors: (i) self-reported unintentional weight loss; (ii) lack of strength and energy; (iii) weakness; (iv) slowness; (v) low level of physical activity. The association between frailty and socio-demographic, behavioral and health factors was measured using the multinomial logistic regression technique. RESULTS: The prevalence of pre-frailty and frailty was 58.7% and 23.8%, respectively. The adjusted regression model showed that the state of pre-frailty was associated with gender, age group and BMI, and frailty was associated with gender, age group, hospitalization, functional capacity, and self-perceived health. CONCLUSION: The evidence presented in this study demonstrates more variables associated with the frailty condition, reinforcing the concept of a multifactorial clinical syndrome that may result in the loss of functionality.OBJETIVO: identificar la prevalencia y los factores asociados a la prefragilidad y fragilidad de ancianos residentes en un municipio con bajo Índice de Desarrollo Humano (IDH=0,635). MÉTODO: estudio transversal de base poblacional y domiciliar realizado en 316 ancianos. La fragilidad fue determinada a partir de la presencia de tres o más de los siguientes factores: (i) autorrelato de pérdida de peso no intencional; (ii) poca resistencia y energía; (iii) debilidad; (iv) lentitud; y (v) bajo nivel de actividad física. La asociación, entre fragilidad y factores sociodemográficos, comportamentales y condiciones de salud, fue verificada por medio de la técnica de regresión logística multinomial. RESULTADOS: la prevalencia de prefragilidad y fragilidad fue de 58,7% y 23,8%, respectivamente. El modelo de regresión ajustado mostró que el estado de prefragilidad fue asociado al sexo, grupo de edad e IMC y la fragilidad fue asociada al sexo, grupo de edad, hospitalización, capacidad funcional y autopercepción de salud. CONCLUSIÓN: las evidencias presentadas en el presente estudio demuestran más variables asociadas a la condición frágil, reforzando el concepto de síndrome clínico de orden multifactorial que puede resultar en la pérdida de funcionalidad.OBJETIVO: identificar a prevalência e os fatores associados à pré-fragilidade e fragilidade de idosos residentes em município com baixo Índice de Desenvolvimento Humano (0,635). MÉTODO: estudo transversal de base populacional e domiciliar, realizado com 316 idosos. A fragilidade foi determinada a partir da presença de três ou mais dos seguintes fatores: (i) autorrelato de perda de peso não intencional; (ii) pouca resistência e energia; (iii) fraqueza; (iv) lentidão e (v) baixo nível de atividade física. A associação entre fragilidade e fatores sociodemográficos, comportamentais e condições de saúde foi verificada por meio da técnica de regressão logística multinomial. RESULTADOS: a prevalência de pré-fragilidade e fragilidade foi de 58,7 e 23,8%, respectivamente. O modelo de regressão ajustado mostrou que o estado de pré-fragilidade foi associado a sexo, grupo etário e índice de massa corporal e fragilidade foi associado ao sexo, grupo etário, hospitalização, capacidade funcional e autopercepção de saúde. CONCLUSÃO: as evidências apresentadas no presente estudo demonstram mais variáveis associadas à condição frágil, reforçando o conceito de síndrome clínica de ordem multifatorial que pode resultar na perda da funcionalidade
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