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Sample records for cercosporiose cercospora coffeicola

  1. Potential of essential oils for the control of brown eye spot in coffee plants Potencial de óleos essenciais no controle da cercosporiose-do-cafeeiro

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    Ricardo Borges Pereira

    2011-02-01

    Full Text Available The objectives of this work were to assess the in vitro effect of essential oils extracted from cinnamon, citronella, lemon grass, India clove, tea tree, thyme, neem and eucalyptus on the conidia germination and on mycelial growth of Cercospora coffeicola, and their efficacy to control the brown eye spot in coffee seedlings (cultivars Catucaí 2SL, Catuaí IAC 62 and Mundo Novo 379/19 in a greenhouse, as well as their effects on the initial germination and infection events by scanning electron microscopy. All essential oils promoted the inhibition of conidia germination with increasing concentrations. India clove, cinnamon, neem, thyme and lemon grass oils inhibited the mycelial growth of C. coffeicola. The cinnamon and citronella oils were the most promising for brown eye spot control in all cultivars. In scanning electron microscopy, the cinnamon and citronella oils reduced germination and mycelial development of C. coffeicola in vivo, eight and 16 hours after inoculation, promoting, in some cases, the leakage of the cellular content. Essential oils of cinnamon and citronella reduced the incidence and severity of brown eye spot, in addition to presenting direct toxicity to the pathogen.Este trabalho avaliou o efeito in vitro de óleos essenciais extraídos de canela, citronela, capim-limão, cravo-da-índia, árvore-de-chá, tomilho, nim e eucalipto na germinação de conídios e no crescimento micelial de Cercospora coffeicola, a eficácia destes óleos no controle da cercosporiose-do-cafeeiro em mudas das cultivares Catucaí 2SL, Catuaí IAC 62 e Mundo Novo 379/19 em casa de vegetação; e seus efeitos sobre os eventos iniciais de germinação e infecção do patógeno in vivo por meio de microscopia eletrônica de varredura. Todos os óleos essenciais inibiram a germinação dos conídios com o aumento das concentrações. Os óleos de cravo-da-índia, canela, nim, tomilho e capim-limão inibiram o crescimento micelial de C. coffeicola. Os

  2. Elaboração e validação de escala diagramática para a cercosporiose do pimentão Development and validation of a diagrammatic key for Cercospora leaf spot of sweet pepper

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    Sami Jorge Michereff

    2006-09-01

    Full Text Available A cercosporiose do pimentão, causada pelo fungo Cercospora capsici, é uma importante doença que ocorre em condições tropicais. Devido à inexistência de métodos padronizados para quantificação desta doença em campo, uma escala diagramática com os níveis de 1,5; 3,5; 8,0; 16,5; 31,0 e 50% de área foliar lesionada foi elaborada e testada para a acurácia, a precisão e a reprodutibilidade das estimativas de severidade da cercosporiose do pimentão, sem e com a sua utilização. Na validação da escala diagramática, 50 folhas com diferentes níveis de severidade da doença, mensurados previamente com o programa AutoCAD®, foram avaliadas por 13 avaliadores, sem e com a utilização da escala diagramática. Foram realizadas duas avaliações com utilização da escala, com intervalo de sete dias, onde seqüências diferentes das mesmas folhas foram estimadas visualmente pelos mesmos avaliadores. A acurácia e a precisão de cada avaliador foi determinada por regressão linear simples, entre a severidade real e a estimada. Sem a escala, oito avaliadores superestimaram significativamente a severidade da doença. Com a escala, os avaliadores obtiveram melhores níveis de acurácia e precisão, embora quatro tendessem a superestimar a severidade, com os erros absolutos concentrando-se abaixo de 10%. Os avaliadores apresentaram boa repetibilidade e elevada reprodutibilidade das estimativas com a utilização da escala, o mesmo não sendo verificado sem a utilização desta. A escala diagramática proposta mostrou-se adequada para avaliação da severidade da cercosporiose do pimentão.Cercospora leaf spot of sweet pepper caused by the fungus Cercospora capsici is an important disease occurring in tropical conditions. Due to the inexistence of standard methods to quantify this disease in field conditions, a diagrammatic key including the levels 1.5, 3.5, 8.0,16.5, 31.0 and 50.0% of diseased leaf area was elaborated and tested for accuracy

  3. Citronella essential oil in the control and activation of coffee plants defense response against rust and brown eye spot Óleo essencial de citronela no controle e na ativação de respostas de defesa do cafeeiro contra a ferrugem e cercosporiose

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    Ricardo Borges Pereira

    2012-08-01

    Full Text Available The rust and brown eye spot are the main coffee diseases. The losses are due to intense defoliation of plants, which has reduced its production and longevity. The brown eye spot also occurs in fruits, with negative effects on the beverage quality. Some essential oils have presented promising results in the control of plant diseases, as an alternative to the use of fungicides. The objective of this study was to evaluate citronella essential oil in the control of rust and brown eye spot and in the activation of coffee plants defense responses. Twelve-month-old plants were sprayed with citronella oil 1000 µL L-1, acibenzolar-S-methyl 200 mg L-1 and tebuconazole fungicide 200 mg L-1. Plants were inoculated with Hemileia vastatrix and Cercospora coffeicola seven days later. The application was repeated after 30 days. Plants with five months were sprayed with the same treatments to assess the induced defense responses. Citronella oil controlled rust and brown eye spot with efficiencies of 47.2% and 29.7%, respectively, while tebuconazole presented control of 96.5% and 90.5%, respectively. Acibenzolar-S-methyl reduced brown eye spot by 55.9% and showed no significant control of rust. Citronella oil increased peroxidase and chitinase activities in five months coffee plants 336, and 24 and 336 hours after spraying, respectively. Acibenzolar-S-methyl increased peroxidase, chitinase and ββ-1,3-glucanase activities 192, 288 and 336; 24 and; 240 hours after spraying, respectively. The treatments did not increase accumulation of phenols, but a significant increase in lignin was observed in plants sprayed with citronella oil.A ferrugem e a cercosporiose são as principais doenças de cafeeiro. Os prejuízos se devem a intensa desfolha das plantas que têm sua produção e longevidade reduzidas. A cercosporiose também ocorre nos frutos, com reflexos negativos na qualidade da bebida. Alguns óleos essenciais têm apresentado resultados promissores no

  4. ACTION OF SILICATO OF CALCIUM AND MAGNESIUM IN THE REDUCTION Cercospora

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    Franciane Diniz Cogo

    2011-07-01

    Full Text Available The aim of this study was to evaluate the response of coffee plants (Coffea arabica Catuaí IAC-44 with different doses of calcium silicate and magnesium in relation to incidence of Cercospora spot coffeicola and plant growth. The experiment was conducted in nursery seedling production of coffee from the Federal Institute of Southern Minas Gerais, Campus Machado, MG randomized blocks with five replications and the treatment used a source of silicon, calcium silicate and magnesium in doses - 0 (control, 75, 150, 225 300 g/m2. The application of silicon in the soil causes the reduction to Cercospora coffeicola. The application of calcium silicate and magnesium affect the growth characteristics and was effective in inducing gray leaf spot, via ground coffee seedlings in nurseries.

  5. ACTION OF SILICATO OF CALCIUM AND MAGNESIUM IN THE REDUCTION Cercospora

    OpenAIRE

    Franciane Diniz Cogo; Gabriel Sergio Graciano; Katia Alves Campos

    2011-01-01

    The aim of this study was to evaluate the response of coffee plants (Coffea arabica) Catuaí IAC-44 with different doses of calcium silicate and magnesium in relation to incidence of Cercospora spot coffeicola and plant growth. The experiment was conducted in nursery seedling production of coffee from the Federal Institute of Southern Minas Gerais, Campus Machado, MG randomized blocks with five replications and the treatment used a source of silicon, calcium silicate and magnesium in doses - 0...

  6. Progresso da ferrugem e da cercosporiose em cafeeiro (coffea arabica l. Com diferentes épocas de início e parcelamentos da fertirrigação Progress of coffee rust and brown eye spot with differents periods at initial irrigation and fertirrigation time

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    Viviane Talamini

    2003-02-01

    Full Text Available Avaliações da incidência da ferrugem (Hemileia vastatrix Berk. & Br. e da cercosporiose (Cercospora coffeicola Berk. & Cooke foram realizadas em experimento com a cultura do café cultivar 'Catuai', com 12 anos de cultivo. Os objetivos foram avaliar o efeito da irrigação e da fertirrigação na incidência da ferrugem e da cercosporiose, analisar a curva de progresso dessas doenças e sua correlação com as variáveis climáticas. O delineamento experimental foi o de blocos ao acaso, com 4 tratamentos de diferentes parcelamentos de adubação (1: 12 aplicações manuais, 2: 12 aplicações via fertirrigação, 3: 24 aplicações fertirrigado, 4: 36 aplicações fertirrigado. As parcelas foram divididas em 3 subparcelas com diferentes épocas de início de irrigação (subparcelas A: 1º de junho, B: 15 de julho, C: 1º de setembro e 2 tratamentos adicionais (testemunhas: tratamento adicional 1- fertirrigação parcelada em 4 vezes e não irrigado; tratamento adicional 2- adubação convencional, não irrigado. Observou-se a incidência de ambas as doenças em 6 folhas por planta a cada 14 dias durante o período de 21 de março de 1998 a 6 de fevereiro de 1999. Calculou-se a área abaixo da curva de progresso da doença (AACPD, procedendo-se à análise de variância e teste de Tukey a 5%. Para a ferrugem do cafeeiro, nenhum tratamento foi significativo, e as incidências máximas foram nos meses de julho a setembro. Houve correlação significativa entre todos os tratamentos e as variáveis climáticas, com exceção da temperatura máxima. Para a cercosporiose, observou-se nas parcelas, maior AACPD para os tratamentos 2 e 4. O tratamento adicional 1 apresentou maior AACPD, seguida pelo tratamento adicional 2 . De acordo com as curvas de progresso da doença, a incidência máxima foi entre maio a setembro. Houve correlação significativa da incidência da cercosporiose com as variáveis climáticas na maioria dos tratamentos

  7. FORMAS DE PENETRAÇÃO DO GÊNERO CERCOSPORA

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    PAULA, Paulo Victor Augusto Azevedo de

    2015-11-01

    Full Text Available The genus Cercospora has species that cause diseases in important crops causing yield losses worldwide. These pathogens are commonly associated with leaf spot symptoms, but can cause injury of flowers, fruits, bracts, pedicels and seeds in various plant families. This review aims to describe the different forms of penetration of the genus Cercospora, causing diseases in crops of commercial importance, such as C. beticola in sugar beet, cassava in C. heningsii, C. coffeicola in coffee, C. sojina in soybean, C. zeae-maydis in corn, C. ricinella in castor and C. kikuchii in soybean. The penetration may occur through the stomata of the leaf of the host can also occur through the epidermal tissue injury and which occur by physical force and/or the action of enzymes directly through the epidermis of the host body. And for the development of the germ tube, different species may develop one or more germ tubes. Then, Cercospora spp has different ways of penetration depending of your host. O gênero Cercospora destaca-se por ser o agente etiológico de doenças em importantes culturas acarretando perdas de produção em todo o mundo. Esses patógenos comumente estão associados a sintomas de manchas foliares, mas podem causar lesões em flores, frutos, brácteas, sementes e pedicelos em diversas famílias de plantas. Essa revisão tem como objetivo descrever as diferentes formas de penetração de espécies do gênero Cercospora, agentes etiológicos de doenças em culturas de grande importância comercial, como C. beticola em beterraba, C. heningsii em mandioca, C. coffeicola em cafeeiro, C. sojina em soja, C. zeae-maydis em milho, C. ricinella em mamona e C. kikuchi em soja. A penetração pode ocorrer através dos estômatos das folhas dos hospedeiros, também pode ocorrer através de ferimentos nos tecidos da epiderme e ainda por força física e/ou ação de enzimas diretamente através da epiderme do órgão do hospedeiro. E em relação ao tubo

  8. Progresso temporal da cercosporiose da beterraba em diferentes genótipos e épocas de semeadura na primavera

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    Leandro Luiz Marcuzzo

    2015-09-01

    Full Text Available A cultura da beterraba tem se intensificado devido ao consumo in natura e também pelo processamento industrial de conservas. Na região do Alto Vale do Itajaí, SC, grande parte da sua produção vem de agricultores familiares que a usam em sucessão a cultura da cebola, com semeadura na primavera/verão. Entretanto, nesta época do ano a cercosporiose (Cercospora beticola tem comprometido a produtividade. O objetivo do trabalho foi avaliar o progresso desta doença nos genótipos: All Green, Stays Green, Early Wonder, Cabernet, Boro, Modana e Itapuã e avaliar a severidade em duas épocas de semeadura, na primavera. Os dois ensaios foram conduzidos na Epagri/Estação Experimental de Ituporanga, implantados com 30 dias de diferença entre as semeaduras. O delineamento experimental foi de blocos casualizados com quatro repetições. Para avaliação da severidade da doença foi utilizada uma escala diagramática em dez plantas ao acaso previamente demarcadas. Os dados de severidade foram submetidos à análise de modelos mistos, area abaixo da curva de progresso de doença, taxa de infecção e severidade final. Não houve diferenças no progresso da doença entre os genótipos avaliados nas duas épocas de semeadura de primavera nas condições do Alto Vale do Itajaí, SC.

  9. Cercospora leaf spot: monitoring and managing fungicide resistance in populations of Cercospora beticola in Michigan

    Science.gov (United States)

    Cercospora leaf spot (CLS, Cercospora beticola) is the most serious foliar disease of sugarbeet in Michigan and Ontario.Management of CLS depends on timely fungicide applications, disease forecasting prediction models and the use of CLS resistant sugar beet varieties. Fungicides have a dominant role...

  10. Electrophoretic karyotype of Cercospora kikuchii.

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    Hightower, R C; Callahan, T M; Upchurch, R G

    1995-02-01

    Classical genetic analyses are not possible with the phytopathogenic fungus Cercospora kikuchii since no sexual stage has been identified. To facilitate gene mapping and to develop an understanding of the genome organization of C. kikuchii, an electrophoretic karyotype has been obtained using contour-clamped homogeneous electric field gel electrophoresis (CHEF). Eight chromosomes, two of which migrate as a doublet, have been separated into seven bands ranging from 2.0 to 5.5 Mb. Using this determination of chromosome number and size, the total genome size of C. kikuchii is estimated to be 28.4 Mb. In addition, genes encoding tubulin, ribosomal DNA, and four previously isolated light-enhanced cDNAs from C. kikuchii were assigned to chromosomes by Southern-hybridization analysis of CHEF blots.

  11. Aerobiologia de Cercospora kikuchii Aerobiology of Cercospora kikuchii

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    Ângela Sathiko Kudo

    2011-10-01

    Full Text Available Neste estudo, foram quantificados os conídios de Cercospora kikuchii [crestamento foliar em soja (Glycine max] presentes no ar, sua relação com a intensidade da doença e com os fatores ambientais [temperatura, umidade relativa do ar (UR, precipitação e molhamento foliar] no período de novembro a março de 2006/07 e 2007/08 em Brasília, DF. Para tanto, foi instalada uma armadilha volumétrica capta-esporos 'Burkard' de sete dias em campo experimental com soja. Houve maior captura de conídios no período diurno, com mais de 60% dos esporos coletados entre 8h e 15h. Os dados climáticos variaram de acordo com a safra, mas, de modo geral, em ambos os experimentos, o período de maior captura de esporos ocorreu quando houve redução da precipitação e do molhamento foliar. A UR acima de 80% e temperatura entre 20 e 24°C foram mais favoráveis para a captura de conídios e a intensidade do crestamento foliar. Nos dois anos de avaliação, a maior quantidade de esporo capturado ocorreu quando a soja se apresentava no estádio R6-R7, assim como a intensidade da doença foi maior após o início do estágio reprodutivo da cultura. Apesar da quantidade de conídio capturado em 2006/07 ter sido maior que em 2007/08, o padrão da flutuação aérea de conídios foi semelhante.The objective of this study was to evaluate the relation of airborne released conidia of Cercospora kikuchii [cercospora leaf blight of soybean (Glycine max] with the disease intensity and some environmental factors [temperature, relative humidity (RH, precipitation and leaf wetness period under experimental field conditions in Brasília, DF, Brazil. The evaluation was from November to March of 2006/07 and 2007/08. Data for the amount of airborne conidia were collected using a Burkard's seven-day volumetric spore trap set in a field with soybean. Most of the conidia were collected during the day, with over 60% of the spores collected between 8h and 15h. Climatic data varied

  12. Effect of crop density of two genotypes of maize in the severity of gray leaf spot and yield in the second season cropInfluência da densidade de cultivo de dois genótipos de milho na severidade da mancha de cercospora e no rendimento de grãos na safrinha

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    Luis Gustavo Amorim Pessoa

    2012-08-01

    Full Text Available Among the diseases that affect the corn crop and can reduce the yield, there is cercospora gray leaf, caused by Cercospora spp. This disease is very important in the second season crop or ‘safrinha’. The objective of this study was to evaluate the severity of cercospora leaf spot in transgenic corn hybrids Agroceres Yieldgard AG 9010 YG and Advance NK Agrisure TL (Bt11, using two plant densities: 78,000 and 100,000 plants per hectare. The results showed that the higher density of plants increased the severity of the disease and provided a lower yield. There was no significant interaction between hybrids and severity of the disease. Entre as doenças que incidem na cultura do milho e podem reduzir seu rendimento, há a mancha de cercospora, causada por Cercospora spp., especialmente importante em milho de segunda época, ou ‘safrinha’. O objetivo deste trabalho foi avaliar a severidade da cercosporiose em nos híbridos transgênicos de milho Agroceres Yieldgard AG 9010 YG e Advance NK Agrisure TL (Bt11, em duas densidades de cultivo: 78.000 e 100.000 plantas por hectare. Os resultados permitiram constatar que a menor densidade de plantas favoreceu o incremento da severidade da doença e proporcionou menor rendimento de grãos. Não houve interação significativa entre os híbridos e a severidade da doença.

  13. Controle químico da Cercosporiose, Mancha-Branca e dos Grãos Ardidos em milho

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    André Humberto Brito

    2013-10-01

    Full Text Available Este trabalho foi realizado com o objetivo de avaliar os efeitos da aplicação de fungicida, no controle da Cercosporiose e da Mancha-Branca do milho, e suas consequências na produtividade de grãos e na incidência de grãos ardidos, além de estabelecer a relação existente entre a produtividade de grãos e a severidade dessas doenças. Dois experimentos distintos (com Azoxystrobina + Cyproconazole e tratamento controle foram conduzidos em três locais, no ano agrícola de 2007/2008. Utilizaram-se 12 híbridos comerciais de milho, que foram avaliados em delineamento de blocos casualizados, com três repetições. Foram realizadas cinco avaliações da severidade das doenças Cercosporiose e Mancha-Branca, por meio de escala de notas, variando de 1 (altamente resistente a 9 (altamente susceptível. Estimou-se a área abaixo da curva de progresso da doença (AACPD. A aplicação de fungicida é eficiente no controle de doenças foliares e na redução da incidência de grãos ardidos, além de proporcionar 12% de aumento na produtividade de grãos, em relação à do tratamento controle. As doenças foliares Cercosporiose e Mancha-Branca reduzem a produtividade de grãos de milho e essa redução é maior quando as doenças ocorrem mais precocemente. A Cercosporiose provoca maior redução na produtividade de grãos, quando comparada com a Mancha-Branca.

  14. Is morphology in Cercospora a reliable reflection of generic affinity?

    NARCIS (Netherlands)

    Bakhshi, Mounes; Arzanlou, Mahdi; Babai-Ahari, Asadollah; Groenewald, Johannes Z.; Crous, Pedro W.

    2015-01-01

    Cercospora (Mycosphaerellaceae) is a large genus of fungi comprising many important plant pathogens. In recent years DNA-based studies have revealed multiple genera of cercosporoid fungi being poly- and paraphyletic. Among these genera, the genus Cercospora has always been perceived as monophyletic.

  15. Molecular characterization of Cercospora beticola and its relatives

    NARCIS (Netherlands)

    Groenewald, M.

    2007-01-01

    The genus Cercospora is one of the largest and most heterogeneous genera of hyphomycetes and contains many important plant pathogens. Generally species of Cercospora are considered to be host-specific at the level of the plant genus or family, and this concept h

  16. Molecular basis of fungicide resistance in Cercospora beticola

    Science.gov (United States)

    Cercospora leaf spot (CLS), caused by the fungus Cercospora beticola, is the most important foliar disease of sugarbeet. Control measures include the application of sterol demethylation inhibitor (DMI) and quinone outside inhibitor (QoI) fungicides. Understanding the molecular mechanism of fungici...

  17. Efeito do meio de cultura e do regime de luz na esporulação de Cercospora zeae-maydis Effect of culture media and light exposure on the sporulation of Cercospora zeae-maydis

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    Kátia Regiane Brunelli

    2006-03-01

    Full Text Available Algumas espécies fúngicas não esporulam satisfatoriamente em meio de cultura, a exemplo de Cercospora zeae-maydis, agente causal da cercosporiose do milho. A esporulação deste patógeno foi avaliada em sete meios de cultura agarizados (V8, suco de tomate temperado, água de coco, aveia, BDA, extrato de folha de milho e extrato de folha de milho + CaCO3 sob dois regimes luminosos (fotoperíodo de 12 horas e seqüencial - 6 dias claro/3 dias escuro. O ensaio foi conduzido em esquema fatorial 7 x 2, com os tratamentos dispostos em delineamento inteiramente casualizado com cinco repetições. A parcela experimental compreendeu uma placa de petri contendo 20 mL de meio de cultura sobre o qual foram colocados 200 mL de uma suspensão de 8 x 10(4 esporos/mL. As culturas foram posteriormente incubadas a 27ºC durante nove dias. Os meios V8 e suco de tomate temperado (STT sob regime de fotoperíodo 12h/12h, foram aqueles que apresentaram melhor indução de esporulação, resultando na produção de 22,4 x 10(4 conídios/ mL e 28,62 x 10(4 conídios/mL, respectivamente.Some fungal species, like Cercospora zeae-maydis, causal agent of maize gray leaf spot, do not satisfactorily produce spores in artificial media. The conidial production of C. zeae-maydis was evaluated on seven culture media (V8, tomato juice, coconut water, oat, PDA, maize leaf extract and maize leaf extract plus CaCO3 under two light exposure regimens (12-hours photoperiod or six days under continuous light followed by three days of continuous darkness. The experiment was arranged as a 7 x 2 factorial design in a completely randomized design with five replicates. A single petri dish containing 20 mL of culture media inoculated with 200 mL of conidial suspension (8 x 10(4 conidia/mL comprised the experimental unit. Plates were incubated at 27ºC for nine days. The highest conidial production was obtained on V8 and tomato juice media under 12-hours photoperiod, resulting in the

  18. Controle genético da resistência da soja à raça 4 de Cercospora sojina

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    Martins Filho Sebastião

    2002-01-01

    Full Text Available O objetivo deste trabalho foi estudar o controle genético da resistência à Cercospora sojina, em populações segregantes derivadas do cruzamento entre as cultivares de soja Paraná e Bossier. Foram avaliadas nos genitores e nas gerações F1, F2, RC1 e RC2 seis características das plantas associadas com a doença: nota para infecção (NT; número de lesões por folíolo (NLF; diâmetro médio de lesão (DML; porcentagem de área foliar lesionada (PAFL; número de lesões por cm² (NLC e índice de doença (ID. A resistência da soja à cercosporiose comportou-se como um caráter quantitativo, e o efeito gênico aditivo o mais importante. As influências sobre NT foram as seguintes: efeito aditivo (62,05%, efeito da dominância (7,68% e as interações epistáticas aditiva x aditiva, aditiva x dominante e dominante x dominante (7,32%. O modelo aditivodominante foi suficiente para explicar as variações somente nos caracteres PAFL e NLC. A influência dos efeitos das interações epistáticas variaram de 2,22% no caráter PAFL e em até 30,78% no caráter DML. O modelo genético aditivo-dominante é satisfatório para explicar o comportamento da média das gerações em relação aos caracteres PAFL e NLC. Entretanto, quanto a NT, NLF, DML e ID, o modelo aditivo-dominante-epistático é o mais adequado.

  19. Novel species of Cercospora and Pseudocercospora (Capnodiales, Mycosphaerellaceae) from Australia.

    Science.gov (United States)

    Shivas, Roger Graham; Marney, Thomas Stephen; Tan, Yu Pei; McTaggart, Alistair Ross

    2015-05-01

    Novel species of Cercospora and Pseudocercospora are described from Australian native plant species. These taxa are Cercospora ischaemi sp. nov. on Ischaemum australe (Poaceae); Pseudocercospora airliensis sp. nov. on Polyalthia nitidissima (Annonaceae); Pseudocercospora proiphydis sp. nov. on Proiphys amboinensis (Amaryllidaceae); and Pseudocercospora jagerae sp. nov. on Jagera pseudorhus var. pseudorhus (Sapindaceae). These species were characterised by morphology and an analysis of partial nucleotide sequence data for the three gene loci, ITS, LSU and EF-1α. Recent divergence of closely related Australian species of Pseudocercospora on native plants is proposed. PMID:25937064

  20. PCR-based detection of fungicide resistance in Cercospora beticola

    Science.gov (United States)

    Leaf spot, caused by the fungus Cercospora beticola, is an endemic disease of sugarbeets in the North Dakota and Minnesota growing regions. Control measures against the fungus include resistant sugarbeet varieties and crop rotation, but the disease is managed effectively only when combined with tim...

  1. A rapid diagnostic tool for detecting benzimidazole resistance in Cercospora beticola, the causal agent of Cercospora leaf spot in sugarbeet

    Science.gov (United States)

    Resistance in Cercospora beticola to benzimidazole fungicides was selected in many sugar beet regions of the world due to extensive use of this fungicide class. Practical resistance to benzimidazole in populations of C. beticola was first reported in Greece in 1973. Resistance has subsequently been ...

  2. Multilocus Sequence Analysis of Cercospora spp. from Different Host Plant Families

    OpenAIRE

    Floreta Fiska Yuliarni; Wellyzar Sjamsuridzal; Iman Hidayat

    2014-01-01

    Identification of the genus Cercospora is still complicated due to the host preferences often being used as the main criteria to propose a new name. We determined the relationship between host plants and multilocus sequence variations (ITS rDNA including 5.8S rDNA, elongation factor 1-α, and calmodulin) in Cercospora spp. to investigate the host specificity. We used 53 strains of Cercospora spp. infecting 12 plant families for phylogenetic analysis. The sequences of 23 strains of ...

  3. Genetic Transformation System for the Fungal Soybean Pathogen Cercospora kikuchii.

    Science.gov (United States)

    Upchurch, R G; Ehrenshaft, M; Walker, D C; Sanders, L A

    1991-10-01

    An altered beta-tubulin gene that confers resistance to the fungicide benomyl was isolated from a genomic library of a UV-induced mutant of Cercospora kikuchii and used as a selectable marker for transformation. The level of benomyl resistance conferred to the transformants was at least 150-fold greater than the intrinsic resistance of the C. kikuchii recipient protoplasts. In the majority of cases, the tubulin fragment was integrated at the native beta-tubulin locus, apparently by gene replacement or gene conversion. The frequency of transformation ranged from 0.2 to 6 transformants per mug of DNA, depending on the recipient strain. Transformation with linearized plasmid resulted in a higher frequency, without changing the type of integration event. Transformants were phenotypically stable after eight consecutive transfers on medium without benomyl. This is the first report of a genetic transformation system for a Cercospora species.

  4. Fungicide sensitivity testing of Cercospora beticola from sugarbeet in the Great Lakes Region

    Science.gov (United States)

    Cercospora leaf spot (CLS), caused by Cercospora beticola (Sacc.), is the most serious foliar disease of sugarbeet (Beta vulgaris L.) worldwide. CLS is problematic in most sugarbeet growing regions and can cause significant economic losses due to decreases in both yield and sugar purity in the harve...

  5. Assessment of strobilurin resistance in Cercospora beticola in on sugar beet in Michigan and Nebraska, USA

    Science.gov (United States)

    Cercospora leaf spot (CLS) caused by Cercospora beticola Sacc. is the most important foliar disease of sugar beet (Beta vulgaris) worldwide. CLS is controlled mainly with fungicides, including strobilurins (FRAC group 11). Resistance to strobilurins in C. beticola was first identified in 2011 from s...

  6. First report of QoI insensitive Cercospora beticola on sugarbeet in Ontario, Canada

    Science.gov (United States)

    Cercospora beticola causes Cercospora leaf spot (CLS) of sugarbeet (Beta vulgaris) and is the most destructive foliar disease of sugarbeet worldwide. The QoI fungicide pyraclostrobin has been an important management tool for CLS in Canada since 2003. Beginning in 2010 some growers reported unsatisf...

  7. More Cercospora Species Infect Soybeans across the Americas than Meets the Eye.

    Science.gov (United States)

    Soares, Ana Paula Gomes; Guillin, Eduardo A; Borges, Leandro Luiz; Silva, Amanda C T da; Almeida, Álvaro M R de; Grijalba, Pablo E; Gottlieb, Alexandra M; Bluhm, Burton H; Oliveira, Luiz Orlando de

    2015-01-01

    Diseases of soybean caused by Cercospora spp. are endemic throughout the world's soybean production regions. Species diversity in the genus Cercospora has been underestimated due to overdependence on morphological characteristics, symptoms, and host associations. Currently, only two species (Cercospora kikuchii and C. sojina) are recognized to infect soybean; C. kikuchii causes Cercospora leaf blight (CLB) and purple seed stain (PSS), whereas C. sojina causes frogeye leaf spot. To assess cryptic speciation among pathogens causing CLB and PSS, phylogenetic and phylogeographic analyses were performed with isolates from the top three soybean producing countries (USA, Brazil, and Argentina; collectively accounting for ~80% of global production). Eight nuclear genes and one mitochondrial gene were partially sequenced and analyzed. Additionally, amino acid substitutions conferring fungicide resistance were surveyed, and the production of cercosporin (a polyketide toxin produced by many Cercospora spp.) was assessed. From these analyses, the long-held assumption of C. kikuchii as the single causal agent of CLB and PSS was rejected experimentally. Four cercosporin-producing lineages were uncovered with origins (about 1 Mya) predicted to predate agriculture. Some of the Cercospora spp. newly associated with CLB and PSS appear to represent undescribed species; others were not previously reported to infect soybeans. Lineage 1, which contained the ex-type strain of C. kikuchii, was monophyletic and occurred in Argentina and Brazil. In contrast, lineages 2 and 3 were polyphyletic and contained wide-host range species complexes. Lineage 4 was monophyletic, thrived in Argentina and the USA, and included the generalist Cercospora cf. flagellaris. Interlineage recombination was detected, along with a high frequency of mutations linked to fungicide resistance in lineages 2 and 3. These findings point to cryptic Cercospora species as underappreciated global considerations for soybean

  8. More Cercospora Species Infect Soybeans across the Americas than Meets the Eye.

    Directory of Open Access Journals (Sweden)

    Ana Paula Gomes Soares

    Full Text Available Diseases of soybean caused by Cercospora spp. are endemic throughout the world's soybean production regions. Species diversity in the genus Cercospora has been underestimated due to overdependence on morphological characteristics, symptoms, and host associations. Currently, only two species (Cercospora kikuchii and C. sojina are recognized to infect soybean; C. kikuchii causes Cercospora leaf blight (CLB and purple seed stain (PSS, whereas C. sojina causes frogeye leaf spot. To assess cryptic speciation among pathogens causing CLB and PSS, phylogenetic and phylogeographic analyses were performed with isolates from the top three soybean producing countries (USA, Brazil, and Argentina; collectively accounting for ~80% of global production. Eight nuclear genes and one mitochondrial gene were partially sequenced and analyzed. Additionally, amino acid substitutions conferring fungicide resistance were surveyed, and the production of cercosporin (a polyketide toxin produced by many Cercospora spp. was assessed. From these analyses, the long-held assumption of C. kikuchii as the single causal agent of CLB and PSS was rejected experimentally. Four cercosporin-producing lineages were uncovered with origins (about 1 Mya predicted to predate agriculture. Some of the Cercospora spp. newly associated with CLB and PSS appear to represent undescribed species; others were not previously reported to infect soybeans. Lineage 1, which contained the ex-type strain of C. kikuchii, was monophyletic and occurred in Argentina and Brazil. In contrast, lineages 2 and 3 were polyphyletic and contained wide-host range species complexes. Lineage 4 was monophyletic, thrived in Argentina and the USA, and included the generalist Cercospora cf. flagellaris. Interlineage recombination was detected, along with a high frequency of mutations linked to fungicide resistance in lineages 2 and 3. These findings point to cryptic Cercospora species as underappreciated global

  9. Progresso da ferrugem e da cercosporiose do cafeeiro consorciado com grevílea, com ingazeiro e a pleno sol em Lavras - MG Progress of rust and coffee plant cercosporiose mixed with grevílea, with ingazeiro and in the full sunshine in Lavras - MG

    Directory of Open Access Journals (Sweden)

    Bruno Grandi Salgado

    2007-08-01

    Full Text Available Com o presente trabalho, objetivou-se avaliar a incidência da ferrugem e da cercosporiose do cafeeiro em diferentes sistemas de cultivo, agroflorestais e a pleno sol, através da curva de progresso dessas doenças. Utilizou-se o delineamento inteiramente casualizado, com três tratamentos e sete repetições. Os tratamentos foram compostos por cafeeiros consorciados com ingazeiro, cafeeiros consorciados com grevílea e cafeeiros cultivados convencionalmente a pleno sol. As avaliações foram realizadas mensalmente no período de abril de 2001 a março de 2003. Realizou-se o cálculo da área abaixo da curva de progresso da doença (AACPD, a qual foi submetida à análise de variância. Para a incidência da ferrugem do cafeeiro o consórcio cafeeiro x ingazeiro mostrou-se com maiores índices da doença, sendo que os tratamentos consórcio cafeeiro x grevílea e cafeeiro a pleno sol não diferiram entre si e apresentaram menores incidências da doença. Diminuição na luz solar direta e maior umidade podem ter favorecido a ferrugem no sistema cafeeiro x ingazeiro. Para a incidência de cercosporiose, os cafeeiros a pleno sol obtiveram maiores valores de incidência da doença, seguidos por cafeeiros x grevílea, e menores taxas da doença foram observadas no consórcio cafeeiros x ingazeiro. A incidência de radiação solar direta pode ter favorecido a maior incidência de cercosporiose nos cafeeiros a pleno sol.The present work aimed to evaluate the incidence of rust and coffee plant cercosporiose in different systems of agroforest cultivation and in the full sunshine through the progress curve of those diseases. The completely randomized design with three treatments and seven replicates was utilized. The treatments were made up of coffee plants mixed with ingazeiro, coffee plants mixed with grevílea and coffee plants cultivated conventionally in the full sunshine. The evaluations were performed monthly during the period of April 2001 to

  10. Vegetative Compatibility Groups in Cercospora kikuchii, the Causal Agent of Cercospora Leaf Blight and Purple Seed Stain in Soybean.

    Science.gov (United States)

    Cai, G; Schneider, R W

    2005-03-01

    ABSTRACT Nitrogen nonutilizing (Nit) mutants were used to assess vegetative compatibility of 58 isolates of Cercospora kikuchii, 55 of which were isolated from soybean plants in Louisiana. Two isolates were vegetatively self-incompatible. Of 56 self-compatible isolates, 16 were assigned to six multimember vegetative compatibility groups (VCGs), 01 to 06, with 2 or 3 isolates in each VCG. The other 40 isolates each belonged to a distinct VCG. All six multimember VCGs contained isolates from different soy bean cultivars, and three included isolates from different locations. Only one of six multimember VCGs included isolates both from soybean leaves and seed, while the other five included isolates from only leaves or seed. The likelihood of tissue specificity or preference was discussed. All isolates and tested Nit mutants produced cercosporin on potato dextrose agar under light. Significantly different amounts of cercosporin were produced among wild-type isolates, and two Nit mutants produced significantly more cercosporin than their wild-type counterparts. All isolates produced typical Cercospora leaf blight symptoms on soybean plants in greenhouse pathogenicity tests.

  11. Transformation of the Fungal Soybean Pathogen Cercospora kikuchii with the Selectable Marker bar.

    Science.gov (United States)

    Upchurch, R G; Meade, M J; Hightower, R C; Thomas, R S; Callahan, T M

    1994-12-01

    An improved transformation protocol, utilizing selection for resistance to the herbicide bialaphos, has been developed for the plant pathogenic fungus Cercospora kikuchii. Stable, bialaphos-resistant transformants are recovered at frequencies eight times higher than those achieved with the previous system that was based on selection for benomyl resistance. In addition to C. kikuchii, this improved method can also be used to transform other species of Cercospora.

  12. Cercospora apii causing leaf spots on two Brazilian toxic weeds: solanum glaucophyllum and Xanthium strumarium

    OpenAIRE

    Fabiano Branco Rocha; Olinto Liparini Pereira; Robert Weingart Barreto

    2007-01-01

    Samples of two toxic weeds, Solanum glaucophyllum and Xanthium strumarium, bearing leaf spots symptoms were found. Cercospora apii was found associated to these leaf spots in both plants. These are the first reports of this fungus on these hosts in Brazil and its first report on S. glaucophyllum worldwide.Foram encontrados plantas das espécies Solanum glaucophyllum e Xanthium strumaruium apresentando sintomas de manchas foliares. Cercospora apii foi encontrado associado lesões foliares em amb...

  13. Mutants of Cercospora kikuchii Altered in Cercosporin Synthesis and Pathogenicity.

    Science.gov (United States)

    Upchurch, R G; Walker, D C; Rollins, J A; Ehrenshaft, M; Daub, M E

    1991-10-01

    We have obtained spontaneous and UV-induced stable mutants, altered in the synthesis of cercosporin, of the fungal soybean pathogen Cercospora kikuchii. The mutants were isolated on the basis of colony color on minimal medium. The UV-induced mutants accumulated, at most, 2% of wild-type cercosporin levels on all media tested. In contrast, cercosporin accumulation by the spontaneous mutants was strongly medium regulated, occurring only on potato dextrose medium but at concentrations comparable to those produced by the wild-type strain. UV-induced mutants unable to synthesize cercosporin on any medium were unable to incite lesions when inoculated onto the soybean host. Cercosporin was reproducibly isolated from all inoculated leaves showing lesions. Although cercosporin involvement in disease has been indirectly suggested by many previous studies, this is the first report in which mutants blocked in cercosporin synthesis have been used to demonstrate that cercosporin is a crucial pathogenicity factor for this fungal genus.

  14. Mutants of Cercospora kikuchii altered in cercosporin synthesis and pathogenicity

    Energy Technology Data Exchange (ETDEWEB)

    Upchurch, R.G.; Walker, D.C.; Rollins, J.A.; Ehrenshaft, M.; Daub, M.E. (North Carolina State Univ., Raleigh (United States))

    1991-10-01

    The authors have obtained spontaneous and UV-induced stable mutants, altered in the synthesis of cercosporin, of the fungal soybean pathogen Cercospora kikuchii. The mutants were isolated on the basis of colony color on minimal medium. The UV-induced mutants accumulated, at most, 2% of wild-type cercosporin levels on all media tested. In contrast, cercosporin accumulation by the spontaneous mutants was strongly medium regulated, occurring only on potato dextrose medium but at concentrations comparable to those produced by the wild-type strain. UV-induced mutants unable to synthesize cercosporin on any medium were unable to incite lesions when inoculated onto the soybean host. Cercosporin was reproducibly isolated from all inoculated leaves showing lesions. Although cercosporin involvement in disease has been indirectly suggested by many previous studies, this is the first report in which mutants blocked in cercosporin synthesis have been used to demonstrate that cercosporin is a crucial pathogenicity factor for this fungal genus.

  15. RNA-sequencing of Cercospora beticola DMI-sensitive and -resistant isolates after treatment with tetraconazole identifies common and contrasting pathway induction

    NARCIS (Netherlands)

    Bolton, Melvin D.; Ebert, Malaika K.; Faino, Luigi; Rivera-Varas, Viviana; Jonge, de Ronnie; Peer, Van de Yves; Thomma, Bart P.H.J.; Secor, Gary A.

    2016-01-01

    Cercospora beticola causes Cercospora leaf spot of sugar beet. Cercospora leaf spot management measures often include application of the sterol demethylation inhibitor (DMI) class of fungicides. The reliance on DMIs and the consequent selection pressures imposed by their widespread use has led to

  16. RNA-Sequencing of Cercospora beticola DMI-sensitive and -resistant isolates after treatment with tetraconazole identifies common and contrasting pathway induction

    Science.gov (United States)

    Cercospora beticola causes Cercospora leaf spot of sugarbeet. Cercospora leaf spot management measures often include application of the sterol demethylation inhibitor (DMI) class of fungicides. The reliance on DMIs and the consequent selection pressures imposed by their widespread use has led to th...

  17. Soybean Resistance to Cercospora sojina Infection Is Reduced by Silicon.

    Science.gov (United States)

    Nascimento, Kelly Juliane Telles; Debona, Daniel; França, Sueny Kelly Santos; Gonçalves, Mariana Gabriele Marcolino; DaMatta, Fábio Murilo; Rodrigues, Fabrício Ávila

    2014-11-01

    Frogeye leaf spot, caused by Cercospora sojina, is one of the most important leaf diseases of soybean worldwide. Silicon (Si) is known to increase the resistance of several plant species to pathogens. The cultivars Bossier and Conquista, which are susceptible and resistant, respectively, to frogeye leaf spot, supplied and nonsupplied with Si were examined for the activities of defense enzymes and the concentrations of total soluble phenolics (TSP) and lignin-thioglycolic acid (LTGA) derivatives at 8, 14, and 16 days after inoculation (dai) with C. sojina. The importance of cell wall degrading enzymes (CWDE) to the infection process of C. sojina and the effect of Si on their activities were also determined. Soybean plants were grown in hydroponic culture containing either 0 or 2 mM Si (-Si and +Si, respectively) and noninoculated or C. sojina inoculated. Severity of frogeye leaf spot was higher in cultivar Bossier plants than cultivar Conquista and also in the +Si plants compared with their -Si counterparts. Except for the concentrations of TSP and LTGA derivatives, activities of defense enzymes and the CWDE did not change for +Si noninoculated plants regardless of the cultivar. The activities of lipoxygenases, phenylalanine ammonia-lyases, chitinases, and polyphenoloxidases as well as the activities of CWDE decreased for the +Si inoculated plants. The results from this study demonstrated that defense enzyme activities decreased in soybean plants supplied with Si, which compromised resistance to C. sojina infection.

  18. A circadian rhythm regulating hyphal melanization in Cercospora kikuchii.

    Science.gov (United States)

    Bluhm, Burton H; Burnham, A Michele; Dunkle, Larry D

    2010-01-01

    Many metabolic and developmental processes in fungi are controlled by biological rhythms. Circadian rhythms approximate a daily (24 h) cycle and have been thoroughly studied in the model fungus, Neurospora crassa. However relatively few examples of true circadian rhythms have been documented among other filamentous fungi. In this study we describe a circadian rhythm underlying hyphal melanization in Cercospora kikuchii, an important pathogen of soybean. After growth in light or light : dark cycles, colonies transferred to darkness produced zonate bands of melanized hyphae interspersed with bands of hyaline hyphae. Rhythmic production of bands was remarkably persistent in the absence of external cues, lasting at least 7 d after transfer to darkness, and was compensated over a range of temperatures. As in N. crassa, blue light but not red light was sufficient to entrain the circadian rhythm in C. kikuchii, and a putative ortholog of white collar-1, one of the genes required for light responses in N. crassa, was identified in C. kikuchii. Circadian regulation of melanization is conserved in other members of the genus: Similar rhythms were identified in another field isolate of C. kikuchii as well as field isolates of C. beticola and C. sorghi, but not in wild-type strains of C. zeae-maydis or C. zeina. This report represents the first documented circadian rhythm among Dothideomycete fungi and provides a new opportunity to dissect the molecular basis of circadian rhythms among filamentous fungi.

  19. [Detection of genetic variability in Cercospora kikuchii isolates from a single soybean field].

    Science.gov (United States)

    Lurá, M C; Di Conza, J A; González, A M; Latorre Rapela, M G; Turino, L; Ibáñez, M M; Iacona, V

    2007-01-01

    Detection of genetic variability in Cercospora kikuchii isolates from a single soybean field. Current knowledge about epidemiology and population structure of Cercospora kikuchii is little developed and no studies regarding this subject have been reported in Argentina. The aim of this work was to select primers to study genetic variability in C. kikuchii isolated from the same soybean field using RAPD (Random Amplified Polymorphism DNA). RAPD was applied to the DNA of 5 C. kikuchii, isolated from diseased tissue of the soybean in the same field, another isolate, from a strain collection. Out of seven primers, five of them proved to be useful to study the population of C. kikuchii isolates.

  20. Cercospora apii causing leaf spots on two Brazilian toxic weeds: solanum glaucophyllum and Xanthium strumarium

    Directory of Open Access Journals (Sweden)

    Fabiano Branco Rocha

    2007-03-01

    Full Text Available Samples of two toxic weeds, Solanum glaucophyllum and Xanthium strumarium, bearing leaf spots symptoms were found. Cercospora apii was found associated to these leaf spots in both plants. These are the first reports of this fungus on these hosts in Brazil and its first report on S. glaucophyllum worldwide.Foram encontrados plantas das espécies Solanum glaucophyllum e Xanthium strumaruium apresentando sintomas de manchas foliares. Cercospora apii foi encontrado associado lesões foliares em ambas as plantas. Estes são os primeiros relatos desse fungo nestes hospedeiros no Brasil e o primeiro relato de sua ocorrência em S. glaucophyllum no mundo.

  1. Population structure of Cercospora kikuchii, the causal agent of Cercospora leaf blight and purple seed stain in soybean.

    Science.gov (United States)

    Cai, G; Schneider, R W

    2008-07-01

    Random amplified polymorphic DNA (RAPD) and microsatellite-primed polymerase chain reaction (MP-PCR) were used to characterize 164 isolates of Cercospora kikuchii, most of which were collected from Louisiana. Plant tissue (seeds versus leaves), but not host cultivar, had a significant impact on pathogen population differentiation. Cluster analysis showed that the Louisiana population was dominated by a primary lineage (group I) with only a few Louisiana isolates belonging to the minor lineage that also included the non-Louisiana isolates (group II). A previous study showed that isolates could be differentiated according to vegetative compatibility groups (VCGs). However, RAPD and MP-PCR data demonstrated that isolates of C. kikuchii were not generally clustered according to these VCGs. Furthermore, genetic relationships within and between VCGs were examined using sequences of the intergenic spacer region of rDNA. These analyses showed that VCG is not an indicator of evolutionary lineage in this fungus. Our results suggest the likely existence of a cryptically functioning sexual stage in some portion of the C. kikuchii population.

  2. Application of the consolidated species concept to Cercospora spp. from Iran

    NARCIS (Netherlands)

    Bakhshi, M.; Arzanlou, M.; Babai-ahari, A.; Groenewald, J.Z.; Braun, U.; Crous, P.W.

    2015-01-01

    The genus Cercospora includes many important plant pathogenic fungi associated with leaf spot diseases on a wide range of hosts. The mainland of Iran covers various climatic regions with a great biodiversity of vascular plants, and a correspondingly high diversity of cercosporoid fungi. However, mos

  3. Development of polymorphic microsatellite and single nucleotide polymorphism markers for Cercospora beticola (Mycosphaerellaceae)

    NARCIS (Netherlands)

    Groenewald, M.; Groenewald, J.Z.; Linde, C.C.; Crous, P.W.

    2007-01-01

    The plant pathogenic fungus, Cercospora beticola, causes the most important foliage disease of sugar beet. A previous study has shown that isolates of opposite mating types are present in equal proportions in natural populations; therefore, the aim of this study was to develop highly reproducible po

  4. Draft Genome Sequence of Cercospora arachidicola, Causal Agent of Early Leaf Spot in Peanuts

    Science.gov (United States)

    Cercospora arachidicola, an economically important pathogen of peanut, is the cause of early leaf spot disease. Despite its significance, insufficient genetic information is available for utilization. Understanding the genetic diversity of this pathogen is crucial for peanut breeding programs to d...

  5. An examination of fungicide sensitivity of Cercospora beticola in Michigan and Ontario sugarbeet (Beta vulgaris) (2014)

    Science.gov (United States)

    Leaf spot caused by Cercospora beticola Sacc. is the major foliar disease of sugarbeet in Michigan. Fungicide applications are one of the most important tools in managing this disease. However, fungicide resistance has developed in C. beticola to several classes of fungicides. To look for the levels...

  6. The disease prevalence and severity of Cercospora leaf spot in sugar beet cultivations in Kayseri

    Directory of Open Access Journals (Sweden)

    Hacer Handan ALTINOK

    2012-12-01

    Full Text Available Cercospora leaf spot disease (Cercospora beticola Sacc., is one of the most economically important fungal diseases in sugar beet growing. Under appropriate climatic conditions, the disease can reach epidemic levels. Although some fungicides exist for disease control, resistance development by pathogen against fungicides is creating difficulties. Besides, use of resistant varieties which is considered as the most efficient and environment-friendly method is adversely affected by pathogen’s ability to exhibit high genetic variations and varying resistance levels against different races of pathogen restricts the success of resistance breeding studies. In order to reveal status of this disease in Kayseri province, surveys were conducted in 2010 and 2011 in sugar beet growing areas and disease prevalence and severity were determined. Approximately, 1500 da area in 90 fields were examined and about 700 da of this area found as infected with Cercospora leaf spot disease in both years of the survey. Highest disease prevalence and severity were found as 80 % and 45 %, respectively, in Sarıoğlan district, which is followed by central district, Develi and Bünyan. Among surveyed districts, lowest prevalence and severity were detected as approx. 65 % and 35 %, respectively, in Yeşilhisar.

  7. Mating type idiomorphs distribution and their correlation to benzimidazole-resistance in Cercospora beticola from the Central High Plains Region, USA

    Science.gov (United States)

    Cercospora leaf spot (CLS) of sugarbeet is caused by Cercospora beticola Sacc., and is one of the most destructive foliar diseases worldwide. Fungicides used for disease suppression include benzimidazoles. Resistance to benzimidazoles can develop quickly, and was first reported in C. beticola in 197...

  8. Use of PCR-RFLP analysis to monitor fungicide resistance in Cercospora beticola populations from sugarbeet (Beta vulgaris) in Michigan, United States

    Science.gov (United States)

    Genetic resistance to Quinone outside inhibitor (QoI) and benzimidazole fungicides may be responsible for a recent decline in efficacy of chemical control management strategies for Cercospora leaf spot (CLS) caused by Cercospora beticola (Sacc.) in Michigan sugarbeet (Beta vulgaris L.) fields. The t...

  9. Characterization and spray drying of lipase produced by the endophytic fungus Cercospora kikuchii

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    T. A. Costa-Silva

    2014-12-01

    Full Text Available A lipase from the endophytic fungus Cercospora kikuchii was purified, biochemically characterized and the effects of spray drying on stabilization of the purified enzyme were studied. The lipase was purified 9.31-fold with recovery of 26.6% and specific activity of 223.6 U/mg. The optimum pH and temperature were 4.6 and 35 ºC, respectively, while the Vmax was 10.28 µmol/min.mg-1 protein and Km 0.0324 mM. All the metal ions tested enhanced the enzyme activity. The lipase retained almost 100% activity in the presence of strong oxidants and was also resistant to Triton X, Tween 80 and 20 and SDS, as well as to proteases. The purified lipase was spray dried and kept until 85.2% of enzymatic activity. At least 70% of the enzymatic activity was maintained for spray dried purified lipase during the storage period. The lipase produced by Cercospora kikuchii has properties useful for industrial application and showed adequate stabilization and retention of its enzymatic activity after spray drying.

  10. CbCTB2, an O-methyltransferase is essential for biosynthesis of the phytotoxin cercosporin and infection of sugar beet by Cercospora beticola

    OpenAIRE

    Staerkel, Cornelia; Boenisch, Marike J; Kröger, Cathrin; Bormann, Jörg; Schäfer, Wilhelm; Stahl, Dietmar

    2013-01-01

    Background Cercospora leaf spot disease, caused by the fungus Cercospora beticola, is the most destructive foliar disease of sugar beets (Beta vulgaris) worldwide. Cercosporin, a light-inducible toxin, is essential for necrosis of the leaf tissue and development of the typical leaf spots on sugar beet leaves. Results In this study we show that the O-methyltransferase gene CTB2 is essential for cercosporin production and pathogenicity in two C. beticola isolates. We established a transformatio...

  11. Adubação orgânica, nutrição e progresso de cercosporiose e ferrugem-do-cafeeiro Organic fertilization, nutrition and the progress of brown eye spot and rust in coffee trees

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    Florisvalda da Silva Santos

    2008-07-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de fontes nutricionais orgânicas, no progresso da cercosporiose e da ferrugem-do-cafeeiro, entre novembro/2003 e novembro/2005. Utilizou-se o delineamento de blocos ao acaso, com quatro repetições e seis tratamentos: palha de café + chorume suíno (PC+CS; torta de mamona + crotalária (TM+Cr; palha de café (PC; esterco bovino + crotalária (EB+Cr; palha de café + torta de mamona (PC+TM; e composto orgânico, torta de mamona, chorume suíno e crotalária (testemunha. A maior área abaixo da curva de progresso da incidência da cercosporiose e da ferrugem foi registrada no tratamento PC (respectivamente 62 e 38% superiores à testemunha. O maior progresso das doenças coincidiu com a elevação no teor de K e redução nos teores de Ca foliares no tratamento PC, comparado às demais fontes de adubação, e resultou em maior desfolha e menor produtividade. Os tratamentos PC+TM e PC+CS reduziram a incidência da cercosporiose em 38% e da ferrugem em 31 e 21%, respectivamente, e aumentou o teor de Ca foliar ao final da fase de granação do cafeeiro, em comparação ao tratamento PC. O equilíbrio nutricional desses cafeeiros conferiu-lhes maior resistência e reduziu o efeito da bienalidade nas safras 2003/2004 e 2004/2005.The objective of this work was to evaluate the effect of organic nutrional sources on the progress of brown eye spot and coffee rust in coffee plants, between November 2003 and November 2005. The experimental design adopted was the randomized blocks, with four replications and six treatment plots: coffee fruit peel + swine waste (CP+SW; castor bean presscake + crotalaria (CBP+Cr; coffee fruit peel (CP; bovine manure + crotalaria (BM+Cr; coffee fruit peel + castor bean presscake (CP+CBP; and standard fertilization used in the farm, which combines compost, castor bean presscake, swine waste and crotalaria (control. The higher area under the incidence progress curves of brown eye

  12. PENGENDALIAN PENYAKIT PATIK (Cercospora nicotianae PADA TEMBAKAU NA OOGST SECARA IN-VIVO DENGAN EKSTRAK DAUN GULMA KIPAHIT (Tithonia diversifolia

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    Aditya Reza Apriyadi

    2013-11-01

    Full Text Available [ENGLISH] Frog eyes diseases or leaf spot caused by Cercospora nicotinae that can reduce the quality of tobacco leaves, especially when used as a cigar deckblad. Affected leaves was easyly torn and the syhmptoms developed rapidly when processed in the storage. Therefore the alternative control of plant is by mexico sun flower leaf extracts. Mexico sunflower belonging to the broadleaf weeds. It suggested contains flavonoids, tannins, terpenoids, and saponins. The results showed mexico sunflower leaf extract concentration 50 g / L was effective to control this diseases, when compared mexico sunflower leaf extract concentration 25 g / L. However, there was no different between plant sprayed with mexico sun flower extract at concentration of 50 g/L and 75 g/L. Keywords: Mexico Sunflower leaf extract; Cercospora nicotianae; Tobacco. [INDONESIAN] Penyakit patik atau bercak daun Cercospora yang disebabkan oleh jamur Cercospora nicotinae dapat mengurangi mutu daun tembakau, terutama apabila digunakan sebagai daun pembalut cerutu. Biasanya penyakit ini dikendalikan dengan pestisida kimia tetapi karena ada batasan residu kimia maksimum sebesar 2,0 ppm, maka dicari alternatif pengendaliannya. Kipahit merupakan gulma berdaun lebar yang mempunyai potensi sebagai anti jamur patogen tanaman, karena mengandung senyawa flavonoid, tannin, terpenoid, dan saponin. Dengan penyemprotan empat kali dalam interval 15 hari, diketahui ekatrak daun kipahit dengan konsentrasi 50 g/l dan 75 g/L dapat menurunkan tingkat keparahan penyakit 1% sejak 60 hst sampai 70 hst. Akan tetapi, nilai insiden penyakit diketahui 100% pada semua perlakuan ekstrak daun kipahit. Ekstrak daun kipahit dengan konsentrasi 50 g/L sudah efektif mengendalikan penyakit patik jika dibandingkan dengan ekstrak daun kipahit dengan konsentrasi 25 g/L. Namun ekstrak daun kipahit dengan konsentrasi 75 g/L tidak berbeda efektifitasnya dengan ekstrak daun kipahit dengan konsentrasi 50 g/L. Kata Kunci: Ekstrak

  13. [Cercospora kikuchii isolated from Province of Santa Fe (Argentina): genetic variability and cercosporin production].

    Science.gov (United States)

    González, Ana María; Turino, Ludmila; Latorre Rapela, María Gabriela; Lurá, María Cristina

    2008-12-31

    The aims of the present study were to analyze the genetic variability of Cercospora kikuchii isolates and the in vitro cercosporin production, of these isolates obtained from soybean at the central-northern region of Santa Fe province (Argentina). Also the relationship between RAPD profiles and toxin production was also assessed. The strain C. kikuchii NBRC 6711 and 13 soybean isolates with symptoms of leaf blight were tested. Cercosporin production was analyzed by growing the fungus on Potato Dextrose Agar, extracting the toxin in alkaline medium and determining its concentration by spectrophotometry. The population of C. kikuchii studied showed variability, both genotypically, nine different groups were encountered, and have the ability to produce cercosporin. No relationship was found between toxin production and the RAPD profiles.

  14. Uji Antagonisme Jamur Endofit Dari Tanaman Padi Terhadap Cercospora oryzae Miyake dan Curvularia lunata (Wakk) Boed. di Laboratorium

    OpenAIRE

    Manurung, Ida Rumia

    2015-01-01

    Ida Rumia Manurung. 2014. “Antagonism Test Between Endophytic Fungi From Rice Against Cercospora oryzae Miyake and Curvularia lunata (Wakk) Boed. in Laboratory”, supervised by Mukhtar Iskandar Pinem and Lahmuddin Lubis. This research aimed to know antagonism ability of endophytic fungi to control C. oryzae and C. lunata in laboratory. This research was held at Plant Disease Laboratory, Agroecotechnology Program Study, Faculty of Agriculture, University of Sumatera Utara with ...

  15. Response of sugar beet plants to ultraviolet-B (280-320 nm) radiation and Cercospora leaf spot disease

    International Nuclear Information System (INIS)

    Sugar beet (Beta vulgaris L.) plants injected with Cercospora beticola Sacc. as well as non-infected plants were grown under visible light with or without ultraviolet-B (UV-B, 280-320 nm) radiation for 40 days. An interaction between UV-B radiation and Cercospora leaf spot disease was observed, resulting in a large reduction in leaf chlorophyll content, dry weight of leaf laminae, petioles and storage roots. Lipid peroxidation in leaves also increased the most under the combined treatments. This was also true for ultraweak luminescence from both adaxial and abaxial leaf surfaces. However, no correlation between lipid peroxidation and ultraweak luminescence was observed. Ultraviolet-B radiation given alone appeared to have either a stimulating effect, giving an increase in dry weight of laminac and reducing lipid peroxidation, or no effect. This lack of effect was seen in the absence of change in dry weight of storage roots and chlorophyll content relative to controls. The study demonstrated a harmful interaction between UV-B radiation and Cercospora leaf spot disease on sugar beet

  16. Herencia de la resistencia al complejo Cercospora spp. en líneas de maíz tropical

    Directory of Open Access Journals (Sweden)

    Narro L. Luis

    2005-09-01

    Full Text Available Se evaluó un diseño dialélico (Griffing Modelo 1 entre 10 líneas endogámicas de maíz tropical contrastantes en su reacción a Cercospora spp. (5 tolerantes y 5 susceptibles, en tres localidades en lotes bajo siembra directa, con presencia natural del patógeno e inoculación artificial, para la variable índice de enfermedad (escala 1 a 5. En el análisis de varianza, por localidad y combinado, los efectos de habilidad combinatoria general (hcg, habilidad combinatoria específica (hce, y recíprocos resultaron altamente significativos; siendo >10 veces mayor los efectos de la hcg que los de hce, indicando predominio de la acción genética aditiva. Resultados también sugieren que la resistencia está controlada por efectos maternos o de citoplasma. La acumulación de genes de resistencia y la conformación de variedades sintéticas tolerantes es una alternativa a implementar en programas del mejoramiento de resistencia a Cercospora de maíces tropicales. ABSTRACT Inheritance of resistance to Cercospora Complex in tropical maize (zea mays inbred lines. Inheritance of resistance to the maize disease complex caused by Cercospora spp on tropical maize was studied by generating and evaluating a diallel mating model (Griffing model I using ten corn inbred lines with contrasting levels of disease reaction (5 tolerant and 5 susceptible. Parental lines and their crosses, both direct and reciprocal, were evaluated in three locations using conservation tillage and inoculated artificially with inoculum prepared using a mixture of foliar maize diseases collected from several farmer’s fields. Analysis of variance for the variable index of disease (scale 1 to 5, both locality and combined, the general combining ability (hcg, specific combining ability (hce, and reciprocal effects were highly significant, with the hcg portion being >10 times greater than the hce component, indicating that the genetic action is predominantly additive. Data

  17. Influence of substrates, light, filter paper and pH on the sporulation of Cercospora sojina

    Directory of Open Access Journals (Sweden)

    Diana Erica Gómez

    2013-06-01

    Full Text Available Fungi require special substrates for their isolation, vegetative growth and sporulation. In experiments conducted in the laboratory, the influence of substrates, light, filter paper and pH on the sporulation of Cercospora sojina conidia, the causal agent of soybean frogeye leaf spot, was assessed. The media potato sucrose agar, V-8 agar, tomato extract agar, soybean leaf extract agar, soybean seed extract agar, soybean meal agar, soybean flour agar and wheat flour agar were tested, added on the surface, with and without filter paper and under two light regimes, with 12 h light at 25°± 2°C and in the dark. A triple factorial 8x2x2 (substrates x light/dark x with/without filter paper design with four replicates was used. V-8 agar medium was employed and the pH was adjusted with HCl 0.1N or NaOH 0.1N before autoclaving to the values: 3, 4, 5, 6, 7 and 8, and the pH of V-8 agar medium is 6.7. The evaluation was done on the seventh day of incubation. Data underwent regression analysis. Sporulation was maximized on the agar media V-8, seed extract, oat flour, tomato extract, and potato sucrose in the presence of filter paper and 12h light. On V-8 medium, maximal sporulation was obtained with pH 6.7.

  18. Immobilization of Lipases Produced by the Endophytic Fungus Cercospora kikuchii on Chitosan Microparticles

    Directory of Open Access Journals (Sweden)

    Lara Aparecida Buffoni Campos Carneiro

    2014-08-01

    Full Text Available This work studied the immobilization of Cercospora kikuchii lipases on chitosan microparticles by chemical attachment on chitosan acetate microparticles activated by glutaraldehyde (CAM added before or after the enzyme and physical adsorption on highly deacetylated chitosan hydrochloride microparticles (CHM. Lipases covalently immobilized on pre-activated CAM showed better performance retaining 88.4% of the enzymatic activity, with 68.2% of immobilization efficiency (IE. The immobilized enzyme retained an activity of about 53.5 % after five reuses, using p-NPP as substrate. Physical adsorption of lipase onto highly deacetylated CHM showed 46.2 % of enzymatic activity and 28.6% of IE. This immobilized derivative did not lose activity up to 80 days of storage at 4°C, while lipases immobilized on pre-activated CAM maintained its activity up to 180 days at same conditions. Taken together the results indicate that chitosan microparticles provide an optimal microenvironment for the immobilized enzyme to maintain good activity and stability.

  19. Genetic Relationships Between Cercospora kikuchii Populations from South America and Japan.

    Science.gov (United States)

    Imazaki, I; Homma, Y; Kato, M; Vallone, S; Yorinori, J T; Henning, A A; Iizumi, H; Koizumi, S

    2006-09-01

    ABSTRACT A collection 160 isolates of Cercospora kikuchii was made from South America and 245 from Japan. DNA fingerprint patterns were analyzed based on amplified fragment length polymorphism among the sample isolates, dividing the isolates into seven lineages (I to VII). Partial nucleotide sequence analyses of the beta-tubulin gene supported this division into seven lineages. Lineages I and III commonly existed in South America and Japan. In all, 136 of the 160 isolates from South America and 223 of the 245 isolates from Japan belonged to lineage I, indicating that lineage I was the major lineage in each area; 5 isolates from South America and 8 isolates from Japan belonged to lineage III. Lineages II (12 isolates) and IV (2 isolates) were specific to Japan and lineages V (3 isolates), VI (1 isolate), and VII (15 isolates) specifically existed in South America. These results suggest that the population genetic structure of C. kikuchii was different between South America and Japan, but the dominance of lineage I was common between the two areas.

  20. Cercospora and Allied Genera in China (Ⅴ)%中国尾孢菌属及其近似属的研究(Ⅴ)

    Institute of Scientific and Technical Information of China (English)

    郭英兰

    2000-01-01

    报道3个中国新记录种:寄生在豆科Leguminosae植物上的葛尾孢Cercospora austrinae Chupp&Viegas和决明尾孢Cercospora cassiocarpa Chupp及寄生在牻牛儿苗科Geraniaceae植物上的老鹳草色链隔孢Phaeoramularia keranii(W.B.Cooke&C.G.Shaw)U.Braun.文中为3个种提供了形态描述.研究的标本保藏在中国科学院微生物研究所菌物标本馆(HMAS).

  1. Characterization of CbCyp51 from field isolates of Cercospora beticola.

    Science.gov (United States)

    Bolton, Melvin D; Birla, Keshav; Rivera-Varas, Viviana; Rudolph, Kurt D; Secor, Gary A

    2012-03-01

    The hemibiotrophic fungus Cercospora beticola causes leaf spot of sugar beet. Leaf spot control measures include the application of sterol demethylation inhibitor (DMI) fungicides. However, reduced sensitivity to DMIs has been reported recently in the Red River Valley sugar beet-growing region of North Dakota and Minnesota. Here, we report the cloning and molecular characterization of CbCyp51, which encodes the DMI target enzyme sterol P450 14α-demethylase in C. beticola. CbCyp51 is a 1,632-bp intron-free gene with obvious homology to other fungal Cyp51 genes and is present as a single copy in the C. beticola genome. Five nucleotide haplotypes were identified which encoded three amino acid sequences. Protein variant 1 composed 79% of the sequenced isolates, followed by protein variant 2 that composed 18% of the sequences and a single isolate representative of protein variant 3. Because resistance to DMIs can be related to polymorphism in promoter or coding sequences, sequence diversity was assessed by sequencing >2,440 nucleotides encompassing CbCyp51 coding and flanking regions from isolates with varying EC(50) values (effective concentration to reduce growth by 50%) to DMI fungicides. However, no mutations or haplotypes were associated with DMI resistance or sensitivity. No evidence for alternative splicing or differential methylation of CbCyp51 was found that might explain reduced sensitivity to DMIs. However, CbCyp51 was overexpressed in isolates with high EC(50) values compared with isolates with low EC(50) values. After exposure to tetraconazole, isolates with high EC(50) values responded with further induction of CbCyp51, with a positive correlation of CbCyp51 expression and tetraconazole concentration up to 2.5 μg ml(-1). PMID:22085297

  2. Isolation of Light-Enhanced cDNAs of Cercospora kikuchii.

    Science.gov (United States)

    Ehrenshaft, M; Upchurch, R G

    1991-09-01

    Cercospora kikuchii is a fungal pathogen of soybeans which produces a photosensitizing phytotoxic polyketide metabolite, cercosporin. Cercosporin synthesis in culture is modulated by several environmental factors. In addition to the light requirement for toxin action, cercosporin biosynthesis is also highly light regulated. As a first step towards identifying genes involved in cercosporin regulation and biosynthesis, we have used subtractive hybridization to isolate light-enhanced cDNA clones. Six distinct cDNA clones representing genes from a wild-type C. kikuchii strain for which transcript accumulation is positively regulated by light were isolated. To assess the relationship of these light-enhanced cDNAs to cercosporin biosynthesis, we compared corresponding steady-state RNA levels in the wild type and in three mutant strains altered in toxin biosynthesis. Two of the mutant C. kikuchii strains which fail to accumulate cercosporin in response to light also fail to exhibit light-enhanced accumulation of transcripts corresponding to all six light-enhanced cDNAs. Cercosporin accumulation in the third mutant strain, S2, is regulated by medium composition as well as light. S2 fails to accumulate cercosporin in complete medium, a medium which allows significant cercosporin accumulation by the wild-type strain. When cultured in complete medium, this mutant strain also fails to show the wild-type, light-enhanced accumulation of transcripts corresponding to five of the six light-enhanced cDNAs. Kinetic analysis demonstrated that transcript accumulation for two of the six light-enhanced cDNAs strongly paralleled cercosporin accumulation in light-grown wild-type culture.

  3. Analyses of expressed sequence tags from the maize foliar pathogen Cercospora zeae-maydis identity novel genes expressed during vegetative infectious, and repoductive growth

    NARCIS (Netherlands)

    Bluhm, B.H.; Lindquist, E.; Kema, G.H.J.; Goodwin, S.B.; Dunkle, L.D.

    2008-01-01

    The ascomycete fungus Cercospora zeae-maydis is an aggressive foliar pathogen of maize that causes substantial losses annually throughout the Western Hemisphere. Despite its impact on maize production, little is known about the regulation of pathogenesis in C. zeae-maydis at the molecular level. The

  4. Non-invasive Presymptomatic Detection of Cercospora beticola Infection and Identification of Early Metabolic Responses in Sugar Beet

    Science.gov (United States)

    Arens, Nadja; Backhaus, Andreas; Döll, Stefanie; Fischer, Sandra; Seiffert, Udo; Mock, Hans-Peter

    2016-01-01

    Cercospora beticola is an economically significant fungal pathogen of sugar beet, and is the causative pathogen of Cercospora leaf spot. Selected host genotypes with contrasting degree of susceptibility to the disease have been exploited to characterize the patterns of metabolite responses to fungal infection, and to devise a pre-symptomatic, non-invasive method of detecting the presence of the pathogen. Sugar beet genotypes were analyzed for metabolite profiles and hyperspectral signatures. Correlation of data matrices from both approaches facilitated identification of candidates for metabolic markers. Hyperspectral imaging was highly predictive with a classification accuracy of 98.5–99.9% in detecting C. beticola. Metabolite analysis revealed metabolites altered by the host as part of a successful defense response: these were L-DOPA, 12-hydroxyjasmonic acid 12-O-β-D-glucoside, pantothenic acid, and 5-O-feruloylquinic acid. The accumulation of glucosylvitexin in the resistant cultivar suggests it acts as a constitutively produced protectant. The study establishes a proof-of-concept for an unbiased, presymptomatic and non-invasive detection system for the presence of C. beticola. The test needs to be validated with a larger set of genotypes, to be scalable to the level of a crop improvement program, aiming to speed up the selection for resistant cultivars of sugar beet. Untargeted metabolic profiling is a valuable tool to identify metabolites which correlate with hyperspectral data. PMID:27713750

  5. The ABC transporter ATR1 is necessary for efflux of the toxin cercosporin in the fungus Cercospora nicotianae.

    Science.gov (United States)

    Amnuaykanjanasin, Alongkorn; Daub, Margaret E

    2009-02-01

    The Cercospora nicotianae mutant deficient for the CRG1 transcription factor has marked reductions in both resistance and biosynthesis of the toxin cercosporin. We cloned and sequenced full-length copies of two genes, ATR1 and CnCFP, previously identified from a subtractive library between the wild type (WT) and a crg1 mutant. ATR1 is an ABC transporter gene and has an open reading frame (ORF) of 4368bp with one intron. CnCFP encodes a MFS transporter with homology to Cercospora kikuchii CFP, previously implicated in cercosporin export, and has an ORF of 1975bp with three introns. Disruption of ATR1 indicated atr1-null mutants had dramatic reductions in cercosporin production (25% and 20% of WT levels) in solid and liquid cultures, respectively. The ATR1 disruptants also showed moderately higher sensitivity to cercosporin. Constitutive expression of ATR1 in the crg1 mutant restored cercosporin biosynthesis and moderately increased resistance. In contrast, CnCFP overexpression in the mutant did not restore toxin production, however, it moderately enhanced toxin resistance. The results together indicate ATR1 acts as a cercosporin efflux pump in this fungus and plays a partial role in resistance.

  6. CFP, the putative cercosporin transporter of Cercospora kikuchii, is required for wild type cercosporin production, resistance, and virulence on soybean.

    Science.gov (United States)

    Callahan, T M; Rose, M S; Meade, M J; Ehrenshaft, M; Upchurch, R G

    1999-10-01

    Many species of the fungal genus Cercospora, including the soybean pathogen C. kikuchii, produce the phytotoxic polyketide cercosporin. Cercosporin production is induced by light. Previously, we identified several cDNA clones of mRNA transcripts that exhibited light-enhanced accumulation in C. kikuchii. Targeted disruption of the genomic copy of one of these, now designated CFP (cercosporin facilitator protein), results in a drastic reduction in cercosporin production, greatly reduced virulence of the fungus to soybean, and increased sensitivity to exogenous cercosporin. Sequence analysis of CFP reveals an 1,821-bp open reading frame encoding a 65.4-kDa protein similar to several members of the major facilitator superfamily (MFS) of integral membrane transporter proteins known to confer resistance to various antibiotics and toxins in fungi and bacteria. We propose that CFP encodes a cercosporin transporter that contributes resistance to cercosporin by actively exporting cercosporin, thus maintaining low cellular concentrations of the toxin.

  7. Tolérance de quelques cultivars de manioc (Manihot esculenta Crantz et de l'espèce sauvage (Manihot glaziovii à la mosaïque virale africaine et à la cercosporiose du manioc

    Directory of Open Access Journals (Sweden)

    Ongono, YSB.

    2007-01-01

    Full Text Available Tolerance of some Cassava Cultivars (Manihot esculenta Crantz and the Wild Species (M. Glaziovii to Cassava Mosaic Virus Disease and Brown Leaf Spot. A study of the tolerance of three cultivars of Manihot esculenta Crantz (one local cultivar, Alot-Bikon, and two improved: IITA 8034, IITA 8061 and wild cassava (M. glaziovii collected from the Mbam and Kim forest (Cameroon towards the cassava mosaic virus disease (CMVD and brown leaf spot (BLS, was carried out in Yaoundé. CMVD was studied under natural conditions, whereas BLS was inoculated through a solution of Cercospora henningsii in concentration around 20 × 10² conidia/ml. Sixteen weeks after planting the cuttings, M. glaziovii plants were tallest (156 cm, whereas highest number of leaves (113 was obtained on the IITA 8061 cultivar. The lowest infection degrees by CMVD (17.2% and BLS (2.7% were registered on the wild species. Consequently, wild species seem to be more tolerant of the diseases studied. IITA 8061 cultivar is moderately resistant to CMVD (28.9% and rather resistant to BLS (7.8%. Cultivars IITA 8034 and the local variety are more sensitive respectively to CMVD (53.1 and 54.5% and BLS (18.8 and 32.8%. The highest yield in tubers was obtained from cultivar IITA 8061 (34.5 t/ha followed by IITA 8034 (32.1 t/ha and local cultivar, Alot-Bbikon (15.6 t/ha. These results show that the tolerance of cassava cultivars to disease has a large influence on tuber yield.

  8. Inibição do crescimento micelial de Cercospora calendulae Sacc. por extratos de plantas medicinais

    Directory of Open Access Journals (Sweden)

    J.M. Nascimento

    2013-01-01

    Full Text Available O uso de extratos e óleos essenciais de plantas medicinais tem sido amplamente estudado no controle de doenças de plantas. O objetivo da realização do presente trabalho foi avaliar o efeito de extratos de Ruta graveolens L., Mentha x villosa, Calendula officinalis L., Momordica charantia L., Symphytum officinale L., Ageratum conyzoides L. e Ricinus comunis L., nas concentrações de 0, 250, 500, 1000, 2000, 5000 e 10000 mg L-1, sobre a inibição do crescimento micelial de Cercospora calendulae Sacc. in vitro. Os extratos foram obtidos por infusão. O experimento foi desenvolvido no Laboratório de Fitopatologia da FCA/UFGD, estado de Mato Grosso do Sul, em delineamento inteiramente casualizado, esquema fatorial 7 extratos x 7 concentrações, com seis repetições. Foi detectado efeito dos extratos e suas concentrações sobre o crescimento do fungo, sendo a interação significativa. Os extratos de calêndula, arruda, hortelã e melão de São Caetano, nas maiores concentrações resultaram em maiores porcentagens de inibição, próximas de 100%, 30%, 35% e 40%, respectivamente, a 10000 mg L-1.

  9. Over-expression of the cercosporin facilitator protein, CFP, in Cercospora kikuchii up-regulates production and secretion of cercosporin.

    Science.gov (United States)

    Upchurch, R G; Rose, M S; Eweida, M

    2001-10-16

    CFP (cercosporin facilitator protein), a light-regulated gene from the soybean fungal pathogen Cercospora kikuchii, encodes the putative major facilitator transporter of the fungal polyketide cercosporin. Gene disruption of CFP in C. kikuchii strain Gus-3 resulted in dramatically reduced cercosporin production and virulence, and increased sensitivity to the toxin. Two C. kikuchii transformant strains (10-1 and 10-11) that over-produce cercosporin were recovered from the complementation of CFP gene-disrupted strain Gus-3. Southern analysis revealed that these strains contained multiple genomic copies of CFP and over-expressed CFP transcript and protein. Although 10-1 and 10-11 produce and secrete significantly elevated levels of cercosporin, they exhibit wild-type resistance to cercosporin, and maintain a wild-type pattern of light-regulated toxin accumulation. Restoration of wild-type cercosporin resistance in 10-1 and 10-11 suggests that CFP does contribute substantially to cercosporin resistance via toxin secretion. The three-fold increase in toxin accumulation, predominantly associated with the mycelium fraction of these CFP multi-copy strains, suggests that CFP may also have a significant, but unknown, role in regulating toxin production.

  10. Genetic diversity of Cercospora kikuchii isolates from soybean cultured in Argentina as revealed by molecular markers and cercosporin production.

    Science.gov (United States)

    Lurá, María Cristina; Latorre Rapela, María Gabriela; Vaccari, María Celia; Maumary, Roxana; Soldano, Anabel; Mattio, Mónica; González, Ana María

    2011-05-01

    Leaf blight and purple seed, caused by the fungal pathogen Cercospora kikuchii (Matsumoto & Tomoyasu) M. W. Gardner are very important diseases of soybean (Glycine max L. Merr.) in Argentina. The aims of this work were: (a) to confirm and to assess the genetic variability among C. kikuchii isolates collected from different soybean growing areas in Santa Fe province using inter simple sequence repeats (ISSR) markers and sequence information from the internal transcribed spacer (ITS) region of rDNA and (b) to analyze the cercosporin production of the regional C. kikuchi isolates in order to assess whether there was any relationship between the molecular profiles and the toxin production. Isolates from different regions in Santa Fe province were studied. The sequence of the ITS regions showed high similarity (99-100%) to the GenBank sequences of C. kikuchii BRCK179 (accession number AY633838). The ISSR markers clustered all the isolates into many groups and cercosporin content was highly variable among isolates. No relationship was observed between ITS region, ISSR groups and origin or cercosporin content. The high degree of genetic variability and cercosporin production among isolates compared in this study characterizes a diverse population of C. kikuchii in the region.

  11. RNA-sequencing of Cercospora beticola DMI-sensitive and -resistant isolates after treatment with tetraconazole identifies common and contrasting pathway induction.

    Science.gov (United States)

    Bolton, Melvin D; Ebert, Malaika K; Faino, Luigi; Rivera-Varas, Viviana; de Jonge, Ronnie; Van de Peer, Yves; Thomma, Bart P H J; Secor, Gary A

    2016-07-01

    Cercospora beticola causes Cercospora leaf spot of sugar beet. Cercospora leaf spot management measures often include application of the sterol demethylation inhibitor (DMI) class of fungicides. The reliance on DMIs and the consequent selection pressures imposed by their widespread use has led to the emergence of resistance in C. beticola populations. Insight into the molecular basis of tetraconazole resistance may lead to molecular tools to identify DMI-resistant strains for fungicide resistance management programs. Previous work has shown that expression of the gene encoding the DMI target enzyme (CYP51) is generally higher and inducible in DMI-resistant C. beticola field strains. In this study, we extended the molecular basis of DMI resistance in this pathosystem by profiling the transcriptional response of two C. beticola strains contrasting for resistance to tetraconazole. A majority of the genes in the ergosterol biosynthesis pathway were induced to similar levels in both strains with the exception of CbCyp51, which was induced several-fold higher in the DMI-resistant strain. In contrast, a secondary metabolite gene cluster was induced in the resistance strain, but repressed in the sensitive strain. Genes encoding proteins with various cell membrane fortification processes were induced in the resistance strain. Site-directed and ectopic mutants of candidate DMI-resistance genes all resulted in significantly higher EC50 values than the wild-type strain, suggesting that the cell wall and/or membrane modified as a result of the transformation process increased resistance to tetraconazole. Taken together, this study identifies important cell membrane components and provides insight into the molecular events underlying DMI resistance in C. beticola. PMID:27112724

  12. Expression in sugar beet of the introduced cercosporin toxin export (CFP) gene from Cercospora kikuchii, the causative organism of purple seed stain in soybean.

    Science.gov (United States)

    Kuykendall, L David; Upchurch, Robert G

    2004-05-01

    The Cercospora kikuchii cercosporin export gene, CFP, introduced into Beta vulgaris L. by conjugation with Rhizobium radiobacter, was stably maintained during vegetative propagation as verified by PCR using primers specific for the CFP gene. Transcriptional expression of the CFP gene in leaves was determined by RT-PCR using CFP-specific primers. CFP protein was detected using Western analysis with an affinity-purified polypeptide-specifc antibody. Analysis of the relative susceptibility of CFP-transgenic and non-transgenic sugar beet plants is planned but will probably take several years to complete.

  13. Reação de genótipos de soja ao crestamento foliar de cercospora

    Directory of Open Access Journals (Sweden)

    Angela Sathiko Kudo

    2011-01-01

    Full Text Available Foram realizados dois experimentos em um delineamento em blocos ao acaso com três repetições, em Cristalina (GO, na safra de 2005/2006, para avaliar a reação de genótipos de soja convencional e transgênica (RR ao crestamento foliar causado por Cercospora kikuchii. No experimento 1, foram avaliados 86 genótipos de soja convencional e no experimento 2, 30 genótipos de soja convencional e transgênica quanto à reação ao crestamento foliar. Como padrões de genótipos convencionais foram usados Emgopa 313 e Msoy 8001 e como genótipos transgênicos Msoy 8585 RR e Msoy 8787 RR. Os genótipos com menor incidência (<1% da doença no experimento 1 foram: GT04-7229, GT04-8987, GT04-8902, GT04-7991, GT04-8218, GT04-9501, GT04-7020, GT04-7505 e GT04-7439. No experimento 2, os menos afetados foram: GT04-7437 RR, GT04-9192 RR, GT04-8091 RR, GT04-8203, GT04-9265 RR e GT04-9085 RR. Não houve diferença na intensidade de doença entre genótipos transgênicos e convencionais. A intensidade do crestamento nos experimentos foi baixa (área foliar lesionada de 0 a 1,5% e incidência de 0 a 20%.

  14. Development of a Quantitative Polymerase Chain Reaction Detection Protocol for Cercospora kikuchii in Soybean Leaves and Its Use for Documenting Latent Infection as Affected by Fungicide Applications.

    Science.gov (United States)

    Chanda, A K; Ward, N A; Robertson, C L; Chen, Z-Y; Schneider, R W

    2014-10-01

    Cercospora leaf blight (CLB) of soybean, caused by Cercospora kikuchii, is a serious disease in the southern United States. A sensitive TaqMan probe-based real-time quantitative polymerase chain reaction (qPCR) assay was developed to specifically detect and quantify C. kikuchii in naturally infected soybean plants. The sensitivity was 1 pg of genomic DNA, which was equivalent to about 34 copies of genome of C. kikuchii. Using this qPCR assay, we documented a very long latent infection period for C. kikuchii in soybean leaves beginning at the V3 growth stage (as early as 22 days after planting). The levels of biomass of C. kikuchii remained low until R1, and a rapid increase was detected from the R2/R3 to R4/R5 growth stages shortly before the appearance of symptoms at R6. The efficacy of various fungicide regimens under field conditions also was evaluated over a 3-year period using this qPCR method. Our results showed that multiple fungicide applications beginning at R1 until late reproductive stages suppressed the development of C. kikuchii in leaves and delayed symptom expression. Different fungicide chemistries also had differential effects on the amount of latent infection and symptom expression during late reproductive growth stages.

  15. EFICIÊNCIA DE PRODUTOS FITOSSANITÁRIOS PULVERIZADOS NA CULTURA DA SOJA (Glycine max L., NO CONTROLE DA MANCHA PARDA (Septoria glycines E CRESTAMENTO FOLIAR-MANCHA PÚRPURA DOS GRÃOS (Cercospora kikuchii EFFICIENCY OF FUNGICIDES IN THE CONTROL OF Septoria glycines AND Cercospora kikuchii ON SOYBEAN (Glycine max L.

    Directory of Open Access Journals (Sweden)

    Alessandro Ramos Nonato

    2007-09-01

    Full Text Available

    Cultura de soja (Glycine max, variedade Crixás, cultivada a campo, naturalmente infectada por Cercospora kikuchii e Septoria glycines, foi pulverizada uma ou duas vezes com diferentes dosagens de produtos fitossanitários. Foram avaliados o nível de infecção nas folhas e sementes, nível de desfolha e rendimento de grãos. Entre os produtos testados, o mais eficiente foi o azoxystrobin, que foi superior ao difeconazole e benomyl, comparando-se à testemunha. Entre os tratamentos com fungicida não houve diferença estatística significante ao nível de 5% de probabilidade, fato este também constatado quando se comparam os tratamentos com fungicida e a testemunha, em relação à produção de grãos.

    PALAVRAS-CHAVE: Soja; Cercospora kikuchii; Septoria glycines.

    Soybean Crixás crop (Glycine max, naturally infected by Cercospora kikuchii and Septoria glycines was sprayed once or twice with different dosages of fungicides. Infection level on leaves and seeds, leaf fall level and seed production were evaluated. Among tested fungicides, the most efficient was azoxystrobin, which was superior to difeconazole and benomyl. All were superior to the control. Among the treatments, there was no significant difference at 5% level. This fact was also noticed when seed yield was compared between treatments and the control.

    KEY-WORDS: Cercospora kikuchii; Septoria glycines; soybean.

  16. Changes occurring in compositions and antioxidant properties of healthy soybean seeds [Glycine max (L.) Merr.] and soybean seeds diseased by Phomopsis longicolla and Cercospora kikuchii fungal pathogens.

    Science.gov (United States)

    Lee, Jin Hwan; Hwang, Seung-Ryul; Lee, Yeon-Hee; Kim, Kyun; Cho, Kye Man; Lee, Yong Bok

    2015-10-15

    Changes in the compositions (isoflavone, protein, oil, and fatty acid) and antioxidant properties were evaluated in healthy soybeans and soybeans diseased by Phomopsis longicolla and Cercospora kikuchii. The total isoflavone content (1491.3 μg/g) of healthy seeds was observed to be considerably different than that of diseased seeds (P. longicolla: 292.6, C. kikuchii: 727.2 μg/g), with malonlygenistin exhibiting the greatest decrease (726.1 → 57.1, 351.9 μg/g). Significantly, three isoflavones exhibited a slight increase, and their structures were confirmed as daidzein, glycitein, and genistein, based on their molecular ions at m/z 253.1, 283.0, and 269.1 using the negative mode of HPLC-DAD-ESI/MS. The remaining compositions showed slight variations. The effects against 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radicals in healthy seeds were stronger than the diseased soybeans, depending upon the isoflavone level. Our results may be useful in evaluating the relationship between composition and antioxidant activity as a result of changes caused by soybean fungal pathogens.

  17. Efeito do tipo de substrato e da presença de adubação suplementar sobre o crescimento vegetativo, nutrição mineral, custo de produção e intensidade de cercosporiose em mudas de cafeeiro formadas em tubetes Effects of substrate type and supplementary fertilization on vegetative growth, mineral nutrition, production costs, and brown eye spot of coffee seedlings in stiff plastic containers

    Directory of Open Access Journals (Sweden)

    Adélia Aziz Alexandre Pozza

    2007-06-01

    Full Text Available A utilização de tubetes para produzir mudas de cafeeiro (Coffea arabica L. tornou-se uma realidade. Objetivando avaliar o uso de substratos adubados ou não com fertilizante de liberação gradual e seus efeitos na nutrição, na formação, na cercosporiose e nos custos de produção de mudas de cafeeiro em tubetes, conduziu-se um experimento em viveiro, em esquema fatorial (4x2 com quatro substratos combinados com duas adubações, tendo quatro repetições. As parcelas foram constituídas por 16 tubetes de 120 mL, considerando-se como plantas úteis as seis centrais. Os tratamentos consistiram dos substratos S1= Substrato comercial I, S2 = Substrato comercial II, S3 = Substrato de eucalipto e S4 = 80% esterco de curral + 20% terra de subsolo, todos com e sem adubação com fertilizante de liberação gradual. No geral, os melhores substratos para formação de mudas de cafeeiro em tubetes foram os substratos não comerciais ou orgânicos, independentemente de receberem ou não adubação suplementar. Observou-se redução da cercosporiose com a nutrição mineral, principalmente com o cálcio. Com a utilização de todos os substratos houve ganho econômico em relação ao custo por milheiro de mudas. A maior economia foi obtida com o substrato S4, seguida do substrato S3, com melhor relação custo/benefício.The utilization of stiff plastic containers for producing coffee seedlings (Coffea arabica L. is a reality. Aiming to evaluate the effects of substrate type enriched or not with slow-release fertilizer on vegetative growth, mineral nutrition, production cost and, brown eye spot of coffee seedlings, an experiment was conducted in the plant nursery. The experimental design was a factorial scheme with four substrates in the presence and absence of supplementary fertilization, with four replicates. The plots were made of 16 containers of 120 ml, using six central plants for evaluation. The treatments consisted of S1 = Commercial Substrate

  18. Efectividad biológica delazoxystrobin para el control de pyricularia oryzae cav. y cercospora oryzae miyake. en arroz de temporal en Veracruz, México

    Directory of Open Access Journals (Sweden)

    Enrique Becerra

    2001-01-01

    Full Text Available El estado de Veracruz, México, siembra anualmente 22000 ha de arroz de temporal con un rendimiento medio de 3,5 t/ha, debido principalmente a problemas de sequía lo cual favorece la presencia de hongos como Pyricularia oryzae Cav. (quema del arroz y Cercospora oryzae Miyake. (Mancha angosta. Con el objeto de conocer el comportamiento de nuevos fungicidas se evaluó la eficacia del Azoxystrobin en el control de estos hongos. El experimento se estableció en el municipio de Tres Valles, Veracruz, durante el temporal de 1999, con semilla de Milagro Filipino Depurado. El diseño estadístico utilizado fue bloques al azar con cuatro repeticiones. Los tratamientos evaluados fueron: Azoxystrobin a 0,2, 0,4 y 0,6 l/ha vs Tecto60 a 0,5 kg/ha y un testigo sin aplicación. Estos fueron aplicados al presentarse los primeros síntomas de las enfermedades. Se evaluó la incidencia, número de lesiones en 20 plantas, índice de intensidad, el rendimiento de grano y fitotoxicidad. Se encontró que el Azoxystrobin obtuvo mejores resultados que el Tecto 60 y éste a su vez que el testigo no tratado. El mejor control para P. oryzae y C. oryzae y el mayor rendimiento de grano (4432 kg/ha se logró cuando se aplicó Azoxystrobin en dosis de 0,6 l/ha, aunque con 0,2 y 0,4 l/ha de este fungicida tuvo un buen control de estas enfermedades. Ninguno de los fungicidas causó toxicidad al arroz

  19. Limiares térmicos para a germinação de conídios de Cercospora sojina em dois regimes luminosos

    Directory of Open Access Journals (Sweden)

    Juliane Nicolodi Camera

    2013-03-01

    Full Text Available O objetivo desse trabalho foi avaliar a germinação de conídios horas, verificou-se que a maior germinação ocorreu na temperatura de Cercospora sojina em diferentes temperaturas com luz contínua de 23,8 ºC, para 6 horas foi de 24,3 ºC, para 9 horas foi de 22,9 ºC e no escuro, visando a determinar os limiares térmicos inferior e e para 12 horas foi de 22,4ºC. Quando as placas foram incubadas superior e a temperatura ótima. Os conídios foram depositados na no escuro, verificou-se que a maior germinação dos conídios para superfície das placas de petri contendo substrato ágar-água. Em o tempo de exposição de 3 horas foi na temperatura de 23,8 ºC, seguida foram incubadas em DBO com luz contínua e no escuro para 6 horas foi de 23,4 ºC, para 9 horas foi de 22,9 ºC e para 12 nas temperaturas (0; 5; 10; 15; 20; 25; 30; 35 e 40 ºC e retiradas horas 22,7 ºC. A temperatura ótima para a germinação de conídios nos tempos de exposição (3, 6, 9 e 12 horas. Para os conídios de na luz contínua foi de 22,4 ºC e no escuro de 23 ºC, sendo o limiar C. sojina submetidos à luz contínua no tempo de exposição de 3 térmico inferior de 0 ºC e o superior de 40 ºC.

  20. Effects of 12 beticolins, Cercospora beticola toxins, on proliferation of ras-transformed adrenocortical cell%真菌Cercospora beticola的12种毒素贝第高林对癌基因ras转导的肾上腺细胞生长的作用

    Institute of Scientific and Technical Information of China (English)

    丁国庆; Gabrielle MAUME; Hanan OSMAN; Martine PADIEU; Marie-Louise MILAT; Claude HUMBERT; Jean-Pierre BLEIN; Bernard F MAUME

    2001-01-01

    AIM: To explore different effects of 12 beticolins, Cercospora beticola toxins, on ras-transformed adrenocortical cell growth inhibition and their functional mechanism.METHODS: Beticolin-induced inhibition was measured with survival cell number determined by an automated photocolorimetric method. The penetration of beticolin was examined by confocal microscopy. Ras protein determined by Lowry method were separated by 14 % SDS-PAGE and electroblotted to Immobilon-P transfer membrane and detected with pan-Ras (Ab-3) monoclonal antibody. The Ca2+ chelation by beticolin was investigated using a calcium ionophore. RESULTS: Cell growth inhibition was found dose- and time-dependently at submicromolar level for beticolin-1, -2, and -13 (IC50 ≤250 nmol/L) and for beticolin-0, 6, and-11 (400 nmol/L < IC50 ≤ 500 nmol/L ). The inhibition by beticolin-1 was immediate, independent of cell culture step and not reversible for 3-day treatment. Beticolin-3 and -4 were slightly active (1 μmol/L < IC50 ≤ 2μmol/L) and beticolin-7, -9, -12, and -5 were inactive at micromolar level. The beticolin-induced cell growth inhibition was correlated with the hydrophobicity of these compounds. Beticolin-1 fluorescence in RTAC cells was detected by confocal microscopy whereas beticolin-3 and -12 were not even after a 24 h incubation period.Beticolin-1-induced cell growth inhibition was partially reverted by calcium ionophore suggesting a role of intracellular Ca2 + chelation by beticolin-1 on cell growth inhibition. Furthermore, beticolin-1 blocked up Ras p21 translocation to membrane and induced accumulation of Ras in the cytosol as an inactive form by different ways.

  1. Preliminary Study on Resistance of Sugar Beet M14 to Cercospora Leaf Spot%甜菜M14品系褐斑病抗性的初步研究

    Institute of Scientific and Technical Information of China (English)

    胡敏; 赵晓菊; 殷亚杰; 武燕

    2009-01-01

    It is of great important to study the cercospora leaf spot resistance of sugar beet M14 which has No. 9 chromosome of Beta corolliflora Zoss. in addition. After spraying with the Cercospora beticola Saec. eonidia sus-pension, enzyme activities in leaves of suger beet M14 and Beta vulgaris L. were experimented, then the amino acid contents in leaves were also analyzed .The results showed that all of the enzyme activities detected in leaves of sugar beet M14 were higher than those in Beta vulgaris L., and the total content of amino acid in suger beet M 14 decreased quickly after infected, while increased in Beta vulgaris L..Therefore, we can conclude that it is valuable to study sugar beet M14 which has resistance to eercospora leaf spot.%甜菜M14品系由于附加了一条野生白花甜菜第9号染色体,因此,研究其是否具有抗病性以及抗病程度的强弱具有十分重要的意义.通过用褐斑病原真菌感染甜菜M14品系与栽培甜菜,对比接种前后叶片中几种酶活性差异,同时对其氨基酸含量进行分析.结果表明:甜菜M14品系植株在感染褐斑病原真菌后所研究的几种酶活性都高于作为对照的栽培甜菜植株;并且甜菜M14品系植株感病后总氨基酸含量下降,而栽培甜菜感病后总氨基酸含量上升.因此,甜菜M14品系具有抗褐斑病的特征,更加具有研究价值.

  2. Diagnóstico e quantificação de doenças fúngicas da acerola no Estado da Paraíba Diagnostic and quantification of barbados cherry diseases in the State of Paraíba, Brazil

    OpenAIRE

    Fernandes A. Almeida; Egberto Araújo; Hermes Gonçalves Junior; Artur F. Barreto; Renato A. G. Carvalho

    2003-01-01

    Objetivando o diagnóstico e quantificação das doenças da acerola (Malpighia emarginata) no Estado da Paraíba, realizou-se um levantamento nas microrregiões do Sertão, Curimatau, Brejo e Litoral. As doenças identificadas foram a cercosporiose (Cercospora sp.), fusariose (Fusarium oxysporum), fumagina (Capnodium sp.), antracnose (Colletotrichum gloeosporioides) e mancha de Alternaria (Alternaria sp.). Além dessas, no teste de patogenicidade, verificou-se o desenvolvimento de lesões circulares, ...

  3. Biological Characteristics of Pathogenic Cercospora sp.Strain F J24 of Water Hyacinth%水葫芦生防菌尾孢霉属菌株FJ24的生物学特性

    Institute of Scientific and Technical Information of China (English)

    龚莲娜; 徐钊; 郑思; 褚建君

    2011-01-01

    测定了从福建省得到的水葫芦致病菌——尾孢霉属菌株FJ24,在不同光照、温度、pH值、碳源、氮源和培养基等条件下菌丝的生长情况.结果表明,全黑暗条件有利于菌丝生长,温度为30℃、pH值为7.6时菌丝生长最快.最适培养基为MDYEA,最适碳源是可溶性淀粉,最适氮源为乙酸铵.%Growth characteristic of fungus threads of water hyacinth pathogenic Cercospora sp. Strain FJ24 collected from Fujian Province was studied under culture in vitro with various environmental factors including light,temperature,pH, carbon source, nitrogen source, medium and so on. The results show that the fungus threads grow best under condition of thorough darkness, and the fungus threads grow fast at 30 ℃ and pH 7.6. MDYEA, soluble starch and acetate ammonium might be the most suitable medium, carbon source and nitrogenous sources respectively.

  4. Study on Biological Characteristics of Cercospora zeae-maydis in Southwest China%西南地区玉米灰斑病菌生物学特性研究

    Institute of Scientific and Technical Information of China (English)

    崔丽娜; 张小飞; 邹成佳; 李晓; 杨晓蓉; 罗怀海

    2012-01-01

    为了进一步防治玉米灰斑病奠定基础,对西南地区玉蜀黍尾孢菌的生物学特性进行了初步研究.结果表明,该病菌生长温度为10 ~35℃,最适生长温度为20~25℃;病原菌对酸碱度的适应范围较广,在pH 4 -11都能生长,以pH 5 ~7为最适pH值;分生孢子萌发温度为5 ~35℃,最适温度为20 ~25℃;光照对菌丝和孢子萌发无显著影响;病原菌最适碳源为葡萄糖,最适氮源为酵母青,致死温度为55℃(10 min).%Some biological characters of Cercospora zeae-maydis were studied in this experiment. The results showed that the pathogen could grow and develop between 10 and 35 ℃ , and the optimum temperature was between 20 and 25 ℃, For growth of the pathogen, there had no strict pH requirement: the favorable pH was 4 -11 and the optimum pH was 5-7. For germination of conidia, the favorable temperature for conidial germination was between 5 and 35 ℃and the optimum temperature was 20 -25 ℃. Effect of light was not obvious on mycelial growth and conidial germination. The optimum carbon source was glucose, and the optimum nitrogen source was yeast extract. The lethal temperature for pathogen was at 55 ℃ for 10 minutes.

  5. Research methodology for maize gray leaf spot:Ⅰ.sporulation of Cercospora zeae-maydis%玉米灰斑病研究方法:Ⅰ.玉米灰斑病菌孢子的培养

    Institute of Scientific and Technical Information of China (English)

    赵正龙; 吴兴兴; 毛自朝; 何月秋

    2011-01-01

    为了明确玉米灰斑病菌的产孢条件,将玉米灰斑病菌接种到马铃薯蔗糖(PSA),燕麦番茄碳酸钙(OTCA)、玉米叶粉碳酸钙(MLPCA)、燕麦粉(OA)、粗面粉(CWPA)等5种培养基上,于25℃下培养,测定该菌生长速度、产孢时间和产孢量.结果表明,菌丝在上述培养基上生长速度均较慢,每天平均生长0.33 nun左右,其中以在OA和PSA上生长速度相对较快.基于上述结果,构建了玉米灰斑病菌孢子培养的二级分段培养法,即将菌丝块接种于加有10~15粒直径为5 mm玻璃珠的马铃薯蔗糖(PS)液体培养基三角瓶里,在25℃,180 r/min条件下振荡培养15 d,形成菌丝悬液,再取菌丝悬浮液涂布在MLPCA培养基上,避光培养13 d左右,可获得大童供接种的分生孢子.长期光照促进菌丝生长,不利于孢子的形成,而长期黑暗不利于菌丝生长,但有利于孢子的形成.%The pathogen of maize gray leaf spot, Cercospora zeae-maydis, was inoculated on potato sucrose agar (PSA), oat tomato plus CaCO3 agar(OTCA), maize leaf powder plus CaCO3 agar(MLPCA), oatmeal agar(OA) and crude wheat powder agar (CWPA), and incubated at 25 ℃ for measuring the mycelial growth, sporulation time and number. The results showed that the mycelia grew very slow on the media, with an average of 0.33 mm per day. They grew fastest on OA and PSA, slower on CWPA and most slowly on MLPCA. Based on the results,a sporulation method was set up, namely two-step culturing method. The mycelia were inoculated into flask with PS and 10-15 glass balls of 5mm diameter, and shaken at 25 ℃ and 180 r/min for 15 days, to culture the mycelial fragment suspension. Then the suspension was smeared on MLPCA medium and incubated for about 13 days at 25 ℃ without light. By this way, a large number of spores could be produced for inoculation. Long illumination promoted the mycelial growth, but on the contrary, long darkness was conducive to sporulation.

  6. Main Diseases and Pests of Coffee and Their Prevention and Control in Yunnan%云南咖啡主要病虫害及防治调查研究①

    Institute of Scientific and Technical Information of China (English)

    刘树芳; 金桂梅; 杨艳鲜; 许叁卫

    2014-01-01

    对云南保山、德宏、普洱等地咖啡病虫害开展调查研究,结果表明院咖啡锈病(Hemileia vastatrix Berk et Br.)、炭疽病(Colletotrichum coffeanum Noack)、褐斑病(Cercospora coffeicola Berk. et Cooke)、幼苗立枯病(Rhizoctonia solani Kuhn.)、旋皮天牛(Acalolepta cervina Hope)、灭字虎天牛(Xylotrechus quadripes Chevr)和根粉蚧(Planococus lilacinus Cockrell)是云南咖啡主要病虫害,其危害较重。根据调查研究结果,提出相应防治方法,为云南咖啡主要病虫害的防治提供依据。%As increasing in cultivated area of coffee and its occurrence of diseases and insects in Yunnan, the study on diseases and insects of coffee and their prevention and control has important significance on sustainable production of coffee. The diseases and insects of coffee were investigated in Baoshan, Dehong, Puer cities in Yunnan of China from 2012-2013. The results showed that Hemileia vastatrix Berk et Br., Colletotrichum coffeanum Noack, Cercospora coffeicola Berk. et Cooke, Rhizoctonia solani Kuhn., Acalolepta cervina Hope, Xylotrechus quadripes Chevr, Planococus lilacinus Cockrell were the main insects and diseases and resulted into higher damage for coffee in Yunnan. According to occurrence and damage of coffee diseases and insects, some corresponding prevention and control methods have been proposed. All these will provide scientific basis for Yunnan coffee production.

  7. Incidência de pragas e doenças em agroecossistemas de café orgânico de agricultores familiares em Poço Fundo-MG Incidence of plagues and diseases in agroecossystems of organic coffee of familiar farmers in Poço Fundo-MG

    Directory of Open Access Journals (Sweden)

    Márcia Martins

    2004-12-01

    Full Text Available Objetivando-se determinar a incidência de pragas Leucoptera coffeella (GUÉRIN-MENÉVILLE, 1842 e Hypothenemus hampei (FERRARI, 1867 e doenças Hemileia vastatrix (BERK e BROOME, 1869 e Cercospora coffeicola (BERK e CURTIS, 1880, durante o período de janeiro de 2001 a dezembro de 2002, foram selecionados três agroecossistemas com produção de café orgânico conduzidos por agricultores familiares do município de Poço Fundo-MG. O agroecossistema I possui 2.200 pés da cultivar 'Catuaí Vermelho' em espaçamento 2,5 x 1,3 m (0,72 ha. O agroecossistema II possui 2.000 pés ('Catuaí Vermelho' em espaçamento 2,8 x 1,0 m (0,56 ha. O agroecossistema III possui 1.100 pés ('Icatu Amarelo' em espaçamento 3,0 x 0,9 m (0,36 ha. A determinação da incidência de L. coffeella, C. coffeicola e H. vastatrix foi realizada mediante levantamentos mensais. A determinação da infecção por C. coffeicola em frutos foi realizada nos meses de abril, maio e junho de 2001 e 2002. O levantamento da infestação por H. hampei foi realizado nos meses de janeiro a junho/julho de cada ano. Determinou-se que a infestação por L. coffeella ultrapassou 20% no terço superior (principalmente no período seco. A infestação por H. hampei atingiu o nível de dano somente no agroecossistema I, em 2001, e no agroecossistema III, em 2002. A infecção por H. vastatrix no agroecossistema III não atingiu nível de dano em conseqüência da tolerância da cultivar ('Icatu' à infecção por esse fungo; porém, nos agroecossistemas I e II ('Catuaí Vermelho', a infecção na lavoura ultrapassou o nível de 10% (principalmente no período seco. A infecção por C. coffeicola em folhas e frutos atingiu níveis elevados (período seco. A produtividade do agroecossistema I, em 2001, foi de 510 Kg ha-1 e, em 2002, de 2.340 Kg ha-1; no agroecossistema II, em 2001, foi de 420 Kg ha-1 e, em 2002, de 1.290 Kg ha-1; e, no agroecossistema III, foi praticamente zero, em 2001, e em

  8. Antifungal activity using medicinal plant extracts against pathogens of coffee tree

    Directory of Open Access Journals (Sweden)

    J.L. Silva

    2014-09-01

    Full Text Available Generally, the medicinal plants have antifungal substances that can be used for the plant protection against phytopathogens. The objective of this study was to know the efficiency of aqueous extracts from medicinal plants against the major etiological agents of coffee tree. The aqueous extracts used were extracted from bulbs of Allium sativum, leaves of Vernonia polysphaera, Cymbopogon citratus, Cymbopogon nardus, Cordia verbenacea, Eucalyptus citriodora, Ricinus communis, Azadirachta indica, Piper hispidinervum and flower buds of Syzygium aromaticum. The etiological agents considered for this study were Cercospora coffeicola, Colletotrichum gloeosporioides, Fusarium oxysporum, Phoma tarda, Rhizoctonia solani and Hemileia vastatrix. The screening for harmful extracts was done based on mycelial growth and conidial germination inhibition. All experiments performed were in vitro conditions. The inhibition of mycelial growth was performed mixing the extracts with the PDA. This mixture was poured in Petri dishes. On the center of the dishes was added one PDA disc with mycelium. It was incubated in a chamber set to 25ºC. The evaluation was done daily by measuring the mycelial growth. The germination assessment was also performed with Petri dishes containing agar-water medium at 2%. These were incubated at 25ºC for 24 hours. After this period the interruption of germination was performed using lactoglycerol. The experiments were conducted in a completely randomized design. The most effective plant extracts against the micelial growth and conidial germination were V. polysphaera, S. aromaticum and A. sativum.

  9. Screening for resistance to purple seed stain Cercospora kikuchii by seed inoculation technique

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, S.H.; Oh, J.H.

    1978-01-01

    An attempt was made to establish a mass-screening technique for resistance to purple seed stain disease in soybean. Seeds sterilized in 1 : 10,000 mercuric chloride for 1 minute and transferred to Petridishes containing 20ml water agar plus 50 ppM of the sodium salt of 2,4-D were inoculated by placing a small agar cube containing fungal mycelium on the seed coat of each seed. A positive correlation betweeen natural infection of purple seed stain and purple discoloration by seed inoculation technique was highly significant and by this technique, some native soybean collections and introduced varieties were tested for resistance to the disease. Most of the soybean varieties tested were susceptible except for the varieties Hill, Harosoy and Sac, resistant comparatively.

  10. Situation de la cercosporiose noire des bananiers et plantains Musa spp. sous différents systèmes de culture à Yangambi, Haut-Zaïre

    Directory of Open Access Journals (Sweden)

    Mobambo, KN.

    1993-01-01

    Full Text Available Black sigatoka situation of bananas and plantains Musa spp. under different farming systems at Yangambi, Upper-Zaire. Black sigatoka, a leaf spot disease, caused by Mycosphaerella fijiensis Morelet seems to be one of the major constraints in the banana and plantain production in Upper-Zaire. Indeed, a survey study undertaken at Yangambi on 12 plantain and 4 banana cultivars revealed that all the observed cultivars were attacked with an exception of banana "Yangambikm 5" which was tolerant. In otherhand, significant differences were observed between bananas and plantains cultivated in fields and those planted in backyards. The regular application of organic matter in backyard farms seems to be one of the major reasons of those differences.

  11. The heterothallic sugarbeet pathogen Cercospora beticola contains exon fragments of both MAT genes that are homogenized by concerted evolution

    NARCIS (Netherlands)

    Bolton, M.D.; Jonge, de R.; Inderbitzin, P.; Liu, Z.; Birla, K.; Peer, Van de Y.; Subbarao, K.; Thomma, B.P.H.J.; Secor, G.

    2014-01-01

    Dothideomycetes is one of the most ecologically diverse and economically important classes of fungi. Sexual reproduction in this group is governed by mating type (MAT) genes at the MAT1 locus. Self-sterile (heterothallic) species contain one of two genes at MAT1 (MAT1-1-1 or MAT1-2-1) and only isola

  12. Biological characteristics of Cercospora fagopyri%荞麦褐斑病菌及其生物学特性

    Institute of Scientific and Technical Information of China (English)

    孟有儒; 李万苍; 李文明

    2004-01-01

    荞麦(Fagopyrum esculentum Moench)富含生物类黄酮、酚类、亚油酸及钙、镁、铜、铁、锌、硒和丰富的维生素等特殊营养成分,具有降血脂、降血糖,软化血管和防病治病等效果。国内大部分省区都有种植,在甘肃历来作为复种作物种植,播种面积较小。随着人民对营养要求多样化和农业种植结构调整,荞麦种植面积逐年扩大,荞麦褐斑病的发生危害愈来愈重,

  13. 大豆紫斑病菌(Cercospora kikuchii)生物学特性研究

    Institute of Scientific and Technical Information of China (English)

    王伟; 衣春生

    1998-01-01

    大豆紫斑病菌在PDA培养基上生长速率最快,在大豆叶葡萄糖琼脂培养基和番茄培养基瞳孢量经在PDA上高2倍,比病菌生长发育最适温度为25-28℃,低于15℃或高于37℃均不适宜,在连续黑暗条件下有利于生长,PH4-9之间,均能生长和产孢以PH-=7生长最适,PH=7-8产孢最多,分生孢子在葡萄糖液中萌发最好,在15-40℃之间均能萌发,最适温度为30-33℃,PH=3-9之间均能萌发,PH=7-8萌发

  14. Controle químico da "ERGOT" (Claviceps africana Frederickson, Mantle & de Milliano ou doença-açucarada e das principais doenças foliares do sorgo (Sorghum bicolor (L. Moench Chemical control of "ERGOT"(Claviceps africana Frederickson, Mantle & de Milliano or sugary disease and the main foliar diseases of sorghum (Sorghum bicolor (L. Moench

    Directory of Open Access Journals (Sweden)

    Nicésio Filadelfo Janssen de Almeida Pinto

    2003-08-01

    Full Text Available O controle químico da "ergot" (Claviceps africana foi realizado em campo de produção de sementes do híbrido de sorgo granífero BR 304 (Sorghum bicolor (L. Moench., utilizando-se os fungicidas (g i.a./ha: captan (1250,0, fenarimol (80,0, trifenil hidróxido de estanho (166,7, prochloraz (450,0, chlorothalonil (1500,0, iprodione (750,0, azoxystrobin (150,0, thiabendazole (360,0, procimidone (750,0, ziram (1500,0 e tebuconazole (200,0. Parcelas sem aplicação de fungicida constituíram a testemunha. As pulverizações foram realizadas com pulverizador costal manual, com o jato dirigido para as panículas. O intervalo das aplicações dos fungicidas foi de 4 dias, a partir da antese. Aos 7 dias após o término das pulverizações, a porcentagem de panículas doentes variou 5,4 para o fungicida tebuconazole e 100,0% para a maioria dos demais tratamentos. Para a porcentagem de flores doentes por panícula, os valores variaram de 0,3% a 65,0% para o fungicida tebuconazole e testemunha, respectivamente. Não ocorreu diferença significativa entre as porcentagens de flores doentes por panículas nos tratamentos tebuconazole (0,3%, chlorothalonil (2,5% e prochloraz (3,0%, sendo esses os mais eficientes no controle da ergot. Adicionalmente, o fungicida mais eficiente no controle da antracnose foliar (Colletotrichum graminicola foi o prochloraz, ao passo que para a ferrugem (Puccinia purpurea e a cercosporiose (Cercospora fusimaculans, o maior controle foi obtido com o fungicida tebuconazole. Não houve aumento da germinação das sementes em nenhum dos tratamentos; entretanto, o aumento do peso de mil sementes foi significativo para os tratamentos com os fungicidas prochloraz, chlorotalonil e tebuconazole.The efficiency of fungicides in the control of sugar disease of sorghum (Sorghum bicolor (L. Moench. was evaluated in a seed production field of the sorghum hybrid BR 304. The following fungicides and doses (g a.i./ha were evaluated : captan (1250

  15. Influência da nutrição mineral na intensidade da mancha-de-olho-pardo em mudas de cafeeiro Influence of the mineral nutrition on intensity of brown-eye spot in young coffee plants

    Directory of Open Access Journals (Sweden)

    Adélia Aziz Alexandre Pozza

    2001-01-01

    Full Text Available Objetivando avaliar a intensidade da mancha-de-olho-pardo do cafeeiro, variedade Catuaí Vermelho, com relação ao estado nutricional das plantas quanto a N e K, realizou-se um experimento no viveiro da Universidade Federal de Viçosa, em Viçosa, MG, utilizando solução nutritiva circulante. Empregaram-se 16 tratamentos, em delineamento inteiramente casualizado, com três repetições e duas plantas por parcela, em esquema fatorial com quatro doses de K (3, 5, 7 e 9mmol/L e quatro doses de N (3, 7, 11 e 15mmol/L. Após sete inoculações de conídios, e avaliações, colheram-se as plantas. A produção de matéria seca total, a área foliar total, e a área abaixo da curva de progresso (AACP do número total de folhas não foram influenciadas pelas doses de K, mas aumentaram com o incremento das doses de N. Observou-se elevação, na AACP, do número de lesões por folha, e na desfolha com o aumento das doses de K e a redução das doses de N. A elevação nas doses de K promoveu redução nos teores foliares de Ca e Cu. Osteores foliares de P, Mg, Mn e Fe não foram influenciados pelas doses de K e tiveram pequena redução com o aumento de N na solução, elevando-se a seguir.The experiment was carried out at the coffee nursery of the Universide Federal de Viçosa, in Viçosa, MG, Brazil, using nutrient circulating solution to evaluate the intensity of brown-eye spot (Cercospora coffeicola, variety Catuaí Vermelho, as a function of N and K. Acompletely randomized design with 16 treatments, three replicates, and two plants per plot was used in a factorial with four levels of K (3, 5, 7 and 9mmol/L combined with four levels of N (3, 7, 11 and 15mmol/L. After seven inoculations and evaluations, the plants were picked. Total dry matter production, total leaf area, and the area below the curve of progress (AACP for the total number of leaves were not influenced by the levels of K, but increased with increasing levels of N. There was increase

  16. Influência de safras agrícolas e tratamentos fungicidas no café cereja descascado e bóia Influence of harvests and fungicide treatments on the parchment and floaters coffee

    Directory of Open Access Journals (Sweden)

    Adriano Andrade Abrahão

    2009-01-01

    Full Text Available O manejo adequado de doenças foliares, como a ferrugem e a cercosporiose do cafeeiro, é fator primordial para a produção de bebidas de qualidade. Nesse sentido, torna-se de extrema importância o conhecimento dos procedimentos técnicos e de produtos fitossanitários, bem como o efeito exercido pelos mesmos na qualidade do café. Objetivou-se, com este trabalho, estudar a qualidade dos grãos de café cereja descascado e bóia procedentes de tratamentos fungicidas, em duas safras agrícolas. Foram conduzidos ensaios nos anos agrícolas 2002/03 e 2003/04. O delineamento utilizado foi o inteiramente casualizado com parcelas subdivididas, utilizando-se quatro repetições, em esquema fatorial 2 x 3 x 2, compreendendo duas safras, três tratamentos fungicidas (fungicida sistêmico, nome comercial Ópera®, fungicida de contato, nome comercial Cobox®, e testemunha não tratada com fungicidas e dois tipos de processamento, cereja descascado e bóia. As avaliações da qualidade dos grãos foram realizadas por meio das análises químicas: acidez titulável, pH, lixiviação de potássio e condutividade elétrica. Os resultados indicaram que os tratamentos fungicidas afetaram apenas a lixiviação de potássio para o café bóia, no qual o Cobox® apresentou menor lixiviação comparado aos demais. Em ambos os processamentos estudados, o segundo ano de ensaio apresentou maior condutividade elétrica, e quando considerado o café bóia, maior lixiviação de potássio. O resultados apontam ainda que, no primeiro ano de ensaio o café cereja descascado apresentou efeito superior para a acidez titulável.The appropriate management of leaf diseases, such as rust and cercospora of the coffee plant, has become extremely important to the production of good quality coffee. In this context, the knowledge of technical procedures and phytosanitary products become extremely important, as well as the effect caused by them in the coffee quality. The objective

  17. Occurrence Reason and Control Measure of Cercospora kikuchii Matsumoto and Tomoyasu%大豆紫斑病发生的原因及综合防治措施

    Institute of Scientific and Technical Information of China (English)

    赵凤玲; 高凤菊

    2008-01-01

    针对德州市2007年大豆收获前阴雨寡照、致使大豆紫斑病严重发生的生产实际,对大豆紫斑病发生的原因、病症、规律、传播途径及综合防治措施进行了研究探讨,为指导今后的大豆生产奠定了理论基础.

  18. Improvement of mungbean by X-ray and thermal neutron irradiation

    International Nuclear Information System (INIS)

    With the aim of improving yield, resistance to Cercospora leaf spot and pod shattering, mungbean varieties Kyunggi No. 5 and M-317 were irradiated with X-rays and thermal neutrons. High yielding mutant lines are generally characterized by a higher number of pods per plant. Better Cercospora resistance appears often associated with later maturity. Satisfactory shattering resistance was not yet obtained. (author)

  19. Fungal Planet description sheets: 69–91

    NARCIS (Netherlands)

    Crous, P.W.; Groenewald, J.Z.; Shivas, R.G.; Edwards, J.; Seifert, K.A.; Alfenas, A.C.; Alfenas, R.F.; Burgess, T.I.; Carnegie, A.J.; Hardy, G.E.St.J.; Hiscock, N.; Hüberli, D.; Jung, T.; Louis-Seize, G.; Okada, G.; Pereira, O.L.; Stukely, M.J.C.; Wang, W.; White, G.P.; Young, A.J.; McTaggart, A.R.; Pascoe, I.G.; Porter, I.J.; Quaedvlieg, W.

    2011-01-01

    Novel species of microfungi described in the present study include the following from Australia: Bagadiella victoriae and Bagadiella koalae on Eucalyptus spp., Catenulostroma eucalyptorum on Eucalyptus laevopinea, Cercospora eremochloae on Eremochloa bimaculata, Devriesia queenslandica on Scaevola t

  20. THE USE OF COADJUTANTS IN TANK MIX WITH FUNGICIDES IN ORDER TO IMPROVE THEIR EFFECTIVENESS EVEN AT LOW DOSAGES

    Directory of Open Access Journals (Sweden)

    Giovanni Campagna

    2006-07-01

    Full Text Available One of the most important items of modern agriculture is the reduction of environmental impact thanks to the integration of new cultivation and protection techniques. Therefore it is important to optimise the use of chemicals and pesticides. We found that some coadjutants applied in tank mix with fungicides on sugar beet protection improve the effectiveness of active principles in cercospora leafspot (Cercospora bieticola sacc. control.

  1. Alternatives agro-écologiques à l’usage des intrants chimiques dans les bananeraies plantains - Le cas de deux régions de la Caraïbe : Guadeloupe et Haïti

    OpenAIRE

    Deloné, Brunise

    2014-01-01

    La banane plantain (Musa paradisiaca) est l’aliment de base de millions de personnes dans le monde et sa culture génère des revenus permanents pour un grand nombre d’agriculteurs, dans des plantations de taille petite ou moyenne. Comme dans d’autres régions tropicales, la culture du plantain en Guadeloupe et en Haïti est soumise à de fortes contraintes parasitaires aussi bien telluriques (i.e. du sol : nématodes phytoparasites et charançon du bananier) qu’aériennes (Cercosporiose noire notamm...

  2. Phylogenetic placement of plant pathogenic Sclerotium species among teleomorph genera.

    Science.gov (United States)

    Xu, Zhihan; Harrington, Thomas C; Gleason, Mark L; Batzer, Jean C

    2010-01-01

    Phylogenetic analyses and morphological characteristics were used to assess the taxonomic placement of eight plant-pathogenic Sclerotium species. Members of this genus produce only sclerotia and no fruiting bodies or spores, so Sclerotium species have been difficult to place taxonomically. Sequences of rDNA large subunit (LSU) and internal transcribed spacer (ITS) regions were determined for isolates of Sclerotium cepivorum, S. coffeicola, S. denigrans, S. hydrophilum, Ceratorhiza oryzae-sativae, S. perniciosum, S. rhizodes, S. rolfsii and S. rolfsii var. delphinii. Parsimony analysis grouped two species previously thought to be in the Basidiomycota, S. denigrans and S. perniciosum, within the Ascomycota; these species were found to have affinities with the teleomorph genera Sclerotinia and Stromatinia and the asexual Sclerotium cepivorum, which was known earlier to be related to Sclerotinia species. The other Sclerotium species were placed in one of two basidiomycetous groups, genera Athelia or Ceratobasidium. Based on rDNA analysis and morphology the basidiomycetous Sclerotium hydrophilum and S. rhizodes were transferred to genus Ceratorhiza, the anamorph of Ceratobasidium species. Sclerotium coffeicola was found to be close to S. rolfsii var. delphinii and S. rolfsii var. rolfsii, which was shown earlier to have an Athelia teleomorph. PMID:20361501

  3. 草本植物三种真菌新病害%Three New Fungous Disease of Forage Grasses

    Institute of Scientific and Technical Information of China (English)

    雷玉明; 张建文

    2006-01-01

    经田间采集、分离培养、室内鉴定及致病性测定.本文报道了寄生于菊科Compositae和桑科Moraceae等9种草本植物上的3种尾孢菌及其病害:蒿褐斑病(Cercospora artenmisiae Y. L. Guo & Y. Jiang)、蓟褐斑病(Cercospora cirsii Ellis & Everh.)和草褐斑病(Cercospora humuligena Y. L. Guo & L. Xu).上述病害在国内外均未见报道,属国内3种新病害,其中9种草本植物为国内新纪录寄主.并对每一种病害的症状和病原形态进行了描述.

  4. BUSCANDO UM BIOHERBICIDA CONTRA Cyperus sp (tiririca

    Directory of Open Access Journals (Sweden)

    Cristine Benfatti Gonzalez

    2001-01-01

    Full Text Available As an alternative to conventional control of Cyperus sp (herbaceousnutsedge, with chemical products, it rises the biological control, making use of phytopathogenic microorganisms. As results of the whole production of Cercospora henningsii e Cercospora caricis by fermentation in potato-dextrose (PD liquid medium, it was observed that both species obtained the optimum growth at 36o C. C. henningsii attained the best value after a period of 72 h of fermentation and C. caricis attained it after 60 h. The field experiments, against Cyperus sp (nutsedge, with the obtained products by liquid fermentation of Cercospora sp (C. henningsii and/or C. caribaea, andwith the use of "wet chamber", proved the pathogenic potential bioherbicide of these microorganisms. = Como alternativa ao controle convencional do Cyperus sp (tiririca usando produtos químicos, surge o controle biológico, empregando-se microrganismos fitopatógenos. Como resultados da produção massal de Cercospora henningsii eCercospora caricis através de cultivo submerso em meio de cultura batata-dextrose (BD, observou-se que ambas espécies obtiveram um crescimento ótimo a 36o C, sendo que para C. henningsii se deu com 72 h de fermentação e para C. caricis com 60 h. Os experimentos de campo, bem como os de Câmara úmida, contra Cyperus sp (tiririca,com os produtos obtidos pelo cultivo submerso de Cercospora sp (C. henningsii e/ou C. caribaea, demonstraram a patogenicidade, ou seja, o potencial bioherbicida desses microrganismos.

  5. Influência do zinco na incidência de doenças do cafeeiro Zinc influence on coffee diseases

    Directory of Open Access Journals (Sweden)

    Vicente Luiz de Carvalho

    2008-06-01

    Full Text Available Em cafeeiros, poucos estudos foram feitos relacionando aumento ou diminuição da resistência das plantas às doenças, com alteração dos níveis de nutrientes utilizados. Com este trabalho, objetivou-se estudar os efeitos do sulfato de zinco aplicado isoladamente, e associado com fungicidas e cloreto de potássio sobre a ferrugem, cercosporiose e manchas foliares do cafeeiro. O trabalho foi desenvolvido em uma lavoura de café em produção, onde foram testados oxicloreto de cobre, tebuconazole, sulfato de zinco + cloreto de potássio e sulfato de zinco e nas subparcelas foram realizadas diferentes concentrações de sulfato de zinco: ausência, 0,3 %, 0,6 % e 1,2 %. Verificou-se que os tratamentos com oxicloreto de cobre e tebuconazole reduziram a incidência e severidade de ferrugem, a incidência de cercosporiose, de manchas foliares (phoma e ascochyta e a desfolha, independente das concentrações de sulfato de zinco utilizadas. Concentrações de sulfato de zinco na faixa de 0,6 % - 0,75 % apresentaram menor severidade da ferrugem e o aumento nas concentrações de sulfato de zinco aumentou a incidência de cercosporiose, manchas foliares e a desfolha dos cafeeiros.The are few studies have been done related to the increase or decrease of disease resistance in coffee plants, with alteration from plant nutrient levels. The ain of this work was to verify the effect of zinc sulfate, applied either alone or in association with fungicides, and the effect of potassium chloride on coffee leaf rust, brown-eyes and leaf stains in coffee plants. Copper oxichloride, tebuconazole, sulfate of zinc + potassium chloride and sulfate of zinc were applied on plots and concentrations of zinc sulfate (0,0 %, 0,3 %, 0,6 % and 1,2 % were applied on sub plot. Treatments with copper and tebuconazole reduced the incidence and severity of rust, the incidence of brown-eyes and stains leaf (phoma and ascochyta and the defoliate independent of the zinc sulfate

  6. Dicty_cDB: Contig-U13942-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 185118 |pid:none) Cercospora zeina strain CPC 11998 ... 44 6e-04 EU644069_1( EU644069 |pid:none) Eupenicillium...L ... 44 0.002 EF626954_1( EF626954 |pid:none) Eupenicillium idahoense NRRL 5274

  7. Fungal Planet 91 – 31 May 2011

    OpenAIRE

    Crous, P.W.; Groenewald, J.Z.; Shivas, R.G.; Edwards, J.; Seifert, K.A.; Alfenas, A.C.; Alfenas, R.F.; Burgess, T.I.; Carnegie, A.J.; Hardy, G.E.St.J.; Hiscock, N.; Hüberli, D.; Jung, T; Louis-Seize, G.; Okada, G.

    2011-01-01

    Novel species of microfungi described in the present study include the following from Australia: Bagadiella victoriae and Bagadiella koalae on Eucalyptus spp., Catenulostroma eucalyptorum on Eucalyptus laevopinea, Cercospora eremochloae on Eremochloa bimaculata, Devriesia queenslandica on Scaevola taccada, Diaporthe musigena on Musa sp., Diaporthe acaciigena on Acacia retinodes, Leptoxyphium kurandae on Eucalyptus sp., Neofusicoccum grevilleae on Grevillea aurea, Phytophthora fluvialis from w...

  8. Genomics of peanut leaf-spot pathogens; and RNA-interference-mediated control of aflatoxins

    Science.gov (United States)

    An overview update of the research done at USDA-ARS National Peanut Research Laboratory will be presented: including: the release of the Cercospora arachidicola genome, sequencing of Cercosporidium personatum, a workflow to study genetic diversity of aflatoxigenic Aspergillus, and progress on the us...

  9. Sugar beet activities of the USDA-ARS East Lansing conducted in cooperation with Saginaw Research & Extension Center during 2014

    Science.gov (United States)

    Evaluation and rating plots were planted at the Saginaw Valley Research & Extension Center (SVREC) in Frankenmuth, MI in 2014 that focused on Cercospora leaf spot (CLS) and Rhizoctonia crown and root rot (CRR) disease performance of a wide range of Beta vulgaris materials. CLS and CRR trials were co...

  10. No Spray' Rose Cultivars for the Mid South

    Science.gov (United States)

    Sixty cultivars of roses, most having disease resistance claims associated with their descriptions in rose catalogs were planted in Tennessee. Plants were evaluated every two weeks from planting until frost for susceptibility to black spot and Cercospora leaf spot using the following scale: 0 = no ...

  11. Doenças da vinagreira no Estado do Maranhão

    OpenAIRE

    Gilson Soares da Silva; Adriano Soares Rêgo; Raycenne Rosa Leite

    2014-01-01

    Neste trabalho, são descritas as principais doenças da vinagreira (Hibiscus sabdariffa) que ocorrem no Estado do Maranhão. Os patógenos identificados foram Cercospora malayensis, Corynespora cassiicola, Lasiodiplodia theobromae, Meloidogyne incognita, Phytophthora nicotianae e Sclerotium rolfsii.

  12. Permanent Genetic Resources added to Molecular Ecology Resources database 1 January 2009-30 April 2009.

    Science.gov (United States)

    Abercrombie, L G; Anderson, C M; Baldwin, B G; Bang, I C; Beldade, R; Bernardi, G; Boubou, A; Branca, A; Bretagnolle, F; Bruford, M W; Buonamici, A; Burnett, R K; Canal, D; Cárdenas, H; Caullet, C; Chen, S Y; Chun, Y J; Cossu, C; Crane, C F; Cros-Arteil, S; Cudney-Bueno, R; Danti, R; Dávila, J A; Della Rocca, G; Dobata, S; Dunkle, L D; Dupas, S; Faure, N; Ferrero, M E; Fumanal, B; Gigot, G; González, I; Goodwin, S B; Groth, D; Hardesty, B D; Hasegawa, E; Hoffman, E A; Hou, M L; Jamsari, A F J; Ji, H J; Johnson, D H; Joseph, L; Justy, F; Kang, E J; Kaufmann, B; Kim, K S; Kim, W J; Koehler, A V; Laitung, B; Latch, P; Liu, Y D; Manjerovic, M B; Martel, E; Metcalfe, S S; Miller, J N; Midgley, J J; Migeon, A; Moore, A J; Moore, W L; Morris, V R F; Navajas, M; Navia, D; Neel, M C; De Nova, P J G; Olivieri, I; Omura, T; Othman, A S; Oudot-Canaff, J; Panthee, D R; Parkinson, C L; Patimah, I; Pérez-Galindo, C A; Pettengill, J B; Pfautsch, S; Piola, F; Potti, J; Poulin, R; Raimondi, P T; Rinehart, T A; Ruzainah, A; Sarver, S K; Scheffler, B E; Schneider, A R R; Silvain, J F; Siti Azizah, M N; Springer, Y P; Stewart, C N; Sun, W; Tiedemann, R; Tsuji, K; Trigiano, R N; Vendramin, G G; Wadl, P A; Wang, L; Wang, X; Watanabe, K; Waterman, J M; Weisser, W W; Westcott, D A; Wiesner, K R; Xu, X F; Yaegashi, S; Yuan, J S

    2009-09-01

    This article documents the addition of 283 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Agalinis acuta; Ambrosia artemisiifolia; Berula erecta; Casuarius casuarius; Cercospora zeae-maydis; Chorthippus parallelus; Conyza canadensis; Cotesia sesamiae; Epinephelus acanthistius; Ficedula hypoleuca; Grindelia hirsutula; Guadua angustifolia; Leucadendron rubrum; Maritrema novaezealandensis; Meretrix meretrix; Nilaparvata lugens; Oxyeleotris marmoratus; Phoxinus neogaeus; Pristomyrmex punctatus; Pseudobagrus brevicorpus; Seiridium cardinale; Stenopsyche marmorata; Tetranychus evansi and Xerus inauris. These loci were cross-tested on the following species: Agalinis decemloba; Agalinis tenella; Agalinis obtusifolia; Agalinis setacea; Agalinis skinneriana; Cercospora zeina; Cercospora kikuchii; Cercospora sorghi; Mycosphaerella graminicola; Setosphaeria turcica; Magnaporthe oryzae; Cotesia flavipes; Cotesia marginiventris; Grindelia Xpaludosa; Grindelia chiloensis; Grindelia fastigiata; Grindelia lanceolata; Grindelia squarrosa; Leucadendron coniferum; Leucadendron salicifolium; Leucadendron tinctum; Leucadendron meridianum; Laodelphax striatellus; Sogatella furcifera; Phoxinus eos; Phoxinus rigidus; Phoxinus brevispinosus; Phoxinus bicolor; Tetranychus urticae; Tetranychus turkestani; Tetranychus ludeni; Tetranychus neocaledonicus; Tetranychus amicus; Amphitetranychus viennensis; Eotetranychus rubiphilus; Eotetranychus tiliarium; Oligonychus perseae; Panonychus citri; Bryobia rubrioculus; Schizonobia bundi; Petrobia harti; Xerus princeps; Spermophilus tridecemlineatus and Sciurus carolinensis.

  13. Soybean Toxin (SBTX) Impairs Fungal Growth by Interfering with Molecular Transport, Carbohydrate/Amino Acid Metabolism and Drug/Stress Responses

    NARCIS (Netherlands)

    Morais, Janne K. S.; Bader, Oliver; Weig, Michael; Oliveira, Jose Tadeu A.; Arantes, Mariana R.; Gomes, Valdirene M.; Da Cunha, Maura; Oliveira, Hermogenes D.; Sousa, Daniele O. B.; Lourencao, Andre L.; Vasconcelos, Ilka M.

    2013-01-01

    Soybean toxin (SBTX) is an antifungal protein from soybeans with broad inhibitory activity against the growth and filamentation of many fungi, including human and plant pathogenic species such as Candida albicans, Candida parapsilosis, Aspergillus niger, Penicillium herquei, Cercospora sojina and Ce

  14. Permanent genetic resources added to molecular ecology resources database 1 January 2009-30 April 2009

    OpenAIRE

    Abercrombie, L. G.; Anderson, C M; Baldwin, B G; Bang, I. C.; Beldade, R.; Bernardi, G.; Boubou, A.; Branca, A; Bretagnolle, F.; Bruford, M. W.; Buonamici, A.; Burnett, R. K.; Canal, D.; Cardenas, H; Caullet, C.

    2009-01-01

    This article documents the addition of 283 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Agalinis acuta; Ambrosia artemisiifolia; Berula erecta; Casuarius casuarius; Cercospora zeae-maydis; Chorthippus parallelus; Conyza canadensis; Cotesia sesamiae; Epinephelus acanthistius; Ficedula hypoleuca; Grindelia hirsutula; Guadua angustifolia; Leucadendron rubrum; Maritrema novaezealandensis; Meretrix meretrix; Nilaparvata luge...

  15. Permanent Genetic Resources added to Molecular Ecology Resources database 1 January 2009-30 April 2009.

    Science.gov (United States)

    Abercrombie, L G; Anderson, C M; Baldwin, B G; Bang, I C; Beldade, R; Bernardi, G; Boubou, A; Branca, A; Bretagnolle, F; Bruford, M W; Buonamici, A; Burnett, R K; Canal, D; Cárdenas, H; Caullet, C; Chen, S Y; Chun, Y J; Cossu, C; Crane, C F; Cros-Arteil, S; Cudney-Bueno, R; Danti, R; Dávila, J A; Della Rocca, G; Dobata, S; Dunkle, L D; Dupas, S; Faure, N; Ferrero, M E; Fumanal, B; Gigot, G; González, I; Goodwin, S B; Groth, D; Hardesty, B D; Hasegawa, E; Hoffman, E A; Hou, M L; Jamsari, A F J; Ji, H J; Johnson, D H; Joseph, L; Justy, F; Kang, E J; Kaufmann, B; Kim, K S; Kim, W J; Koehler, A V; Laitung, B; Latch, P; Liu, Y D; Manjerovic, M B; Martel, E; Metcalfe, S S; Miller, J N; Midgley, J J; Migeon, A; Moore, A J; Moore, W L; Morris, V R F; Navajas, M; Navia, D; Neel, M C; De Nova, P J G; Olivieri, I; Omura, T; Othman, A S; Oudot-Canaff, J; Panthee, D R; Parkinson, C L; Patimah, I; Pérez-Galindo, C A; Pettengill, J B; Pfautsch, S; Piola, F; Potti, J; Poulin, R; Raimondi, P T; Rinehart, T A; Ruzainah, A; Sarver, S K; Scheffler, B E; Schneider, A R R; Silvain, J F; Siti Azizah, M N; Springer, Y P; Stewart, C N; Sun, W; Tiedemann, R; Tsuji, K; Trigiano, R N; Vendramin, G G; Wadl, P A; Wang, L; Wang, X; Watanabe, K; Waterman, J M; Weisser, W W; Westcott, D A; Wiesner, K R; Xu, X F; Yaegashi, S; Yuan, J S

    2009-09-01

    This article documents the addition of 283 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Agalinis acuta; Ambrosia artemisiifolia; Berula erecta; Casuarius casuarius; Cercospora zeae-maydis; Chorthippus parallelus; Conyza canadensis; Cotesia sesamiae; Epinephelus acanthistius; Ficedula hypoleuca; Grindelia hirsutula; Guadua angustifolia; Leucadendron rubrum; Maritrema novaezealandensis; Meretrix meretrix; Nilaparvata lugens; Oxyeleotris marmoratus; Phoxinus neogaeus; Pristomyrmex punctatus; Pseudobagrus brevicorpus; Seiridium cardinale; Stenopsyche marmorata; Tetranychus evansi and Xerus inauris. These loci were cross-tested on the following species: Agalinis decemloba; Agalinis tenella; Agalinis obtusifolia; Agalinis setacea; Agalinis skinneriana; Cercospora zeina; Cercospora kikuchii; Cercospora sorghi; Mycosphaerella graminicola; Setosphaeria turcica; Magnaporthe oryzae; Cotesia flavipes; Cotesia marginiventris; Grindelia Xpaludosa; Grindelia chiloensis; Grindelia fastigiata; Grindelia lanceolata; Grindelia squarrosa; Leucadendron coniferum; Leucadendron salicifolium; Leucadendron tinctum; Leucadendron meridianum; Laodelphax striatellus; Sogatella furcifera; Phoxinus eos; Phoxinus rigidus; Phoxinus brevispinosus; Phoxinus bicolor; Tetranychus urticae; Tetranychus turkestani; Tetranychus ludeni; Tetranychus neocaledonicus; Tetranychus amicus; Amphitetranychus viennensis; Eotetranychus rubiphilus; Eotetranychus tiliarium; Oligonychus perseae; Panonychus citri; Bryobia rubrioculus; Schizonobia bundi; Petrobia harti; Xerus princeps; Spermophilus tridecemlineatus and Sciurus carolinensis. PMID:21564911

  16. Doenças da vinagreira no Estado do Maranhão

    Directory of Open Access Journals (Sweden)

    Gilson Soares da Silva

    2014-12-01

    Full Text Available Neste trabalho, são descritas as principais doenças da vinagreira (Hibiscus sabdariffa que ocorrem no Estado do Maranhão. Os patógenos identificados foram Cercospora malayensis, Corynespora cassiicola, Lasiodiplodia theobromae, Meloidogyne incognita, Phytophthora nicotianae e Sclerotium rolfsii.

  17. Effect of genotype on sugar beet yield and quality

    Directory of Open Access Journals (Sweden)

    Nenadić N.

    2003-01-01

    Full Text Available The effect of a considerable number of both domestic and foreign sugar beet genotypes on root yield and quality was investigated. The data demonstrated the most favorable results of some genotypes for root yield and sugar content. Trials were conducted on rhizomania infested soil, thus tolerant genotypes were used. Susceptible cultivars represented the control. In the trial root yield was high and sugar content low. On average, in the genotypes tested, root yield varied from 73.98 to 93.30 t/ha and sugar content from 11.90 to 13.36%, depending on weather conditions. Root yield of the genotypes investigated varied from 30.61 to 112.64 t/ha and sugar content from 10.60 to 14.20%. The Swedish cultivar Dorotea (tolerant to both rhizomania and cercospora was the most yielding. The least yielding (susceptible to both rhizomania and cercospora was the domestic cultivar Dana.

  18. Design, Synthesis, and Fungicidal Activities of Novel 5-Methyl-1H-1,2,3- trizole-4-carboxyl Amide Analogues.

    Science.gov (United States)

    Wang, Zhen-Jun; Yang, Hui-Hui; Tian, Lei; Zhao, Wei-Guang

    2016-01-01

    Succinate dehydrogenase inhibitors (SDHIs) are fungicides with an amide bond widely used to control plant diseases caused by phytopathogenic fungi. Because of broad spectrum activity of new SDHIs, they have attracted wide attention from the research community. A series of structurally novel SDHIs with a bioactive 1,2,3-triazole moiety were designed and synthesized. Bioactivity screening showed that some of designed N-phenethyl-1,2,3-trizole-4-carboxyl amide analogues exhibited good fungicidal activities toward Sclerotinia sclerotiorum and Botrytis cinerea, while some of Nbenzyl- 1,2,3-trizole-4-carboxyl amide analogues exhibited good fungicidal activities toward Phytophthora capsici and Cercospora arachidicola. EC50 value of compound 5d against Cercospora arachidicola (6.6 µg/mL) was lower than that of chlorothalonil (12.3 µg/mL). PMID:26558376

  19. Transgenic assessment of CFP-mediated cercosporin export and resistance in a cercosporin-sensitive fungus.

    Science.gov (United States)

    Upchurch, Robert G; Rose, Mark S; Eweida, Mohamed; Callahan, Terrence M

    2002-04-01

    Cercosporin is a toxic polyketide produced by many phytopathogenic members of the fungal genus Cercospora. Cercospora species, themselves, exhibit the highest level of self-resistance to this almost universally toxic photosensitizer. Although the mechanism of cercosporin self-resistance is multi-faceted, partial resistance does appear to be provided by the encoded product of CFP ( cercosporin facilitator protein), a gene recently isolated from the pathogen of soybean, C. kikuchii. CFP has significant similarity to the major facilitator superfamily of integral membrane transport proteins. We expressed CFP in the cercosporin non-producing, cercosporin-sensitive fungus, Cochliobolus heterostrophus, in order to assess the transport activity of CFP and the contribution of CFP to cercosporin resistance in a fungal species free of endogenous toxin production. Expression of the CFP transgene in this fungus results in increased resistance to cercosporin due, apparently, to its export out of the fungus.

  20. Identification of Immunity Related Genes to Study the Physalis peruviana – Fusarium oxysporum Pathosystem

    OpenAIRE

    Enciso-Rodríguez, Felix E.; Carolina González; Rodríguez, Edwin A.; Camilo E López; David Landsman; Luz Stella Barrero; Leonardo Mariño-Ramírez

    2013-01-01

    The Cape gooseberry ( Physalis peruviana L) is an Andean exotic fruit with high nutritional value and appealing medicinal properties. However, its cultivation faces important phytosanitary problems mainly due to pathogens like Fusarium oxysporum, Cercospora physalidis and Alternaria spp. Here we used the Cape gooseberry foliar transcriptome to search for proteins that encode conserved domains related to plant immunity including: NBS (Nucleotide Binding Site), CC (Coiled-Coil), TIR (Toll/Inter...

  1. Pathogenicity of seed-borne and seedling fungi of groundnut cv. Tatu/
    Patogenicidade de fungos associados às sementes e plântulas de amendoim cv. Tatu

    OpenAIRE

    Débora Cristina Santiago; Édison Miglioranza; Romeu Munashi Endo; Nair Mieko Takaki Bellettini

    2005-01-01

    Seeds and seedlings of groundnut (Arachis hypogaea) cv. Tatu were investigated under laboratory and green house conditions to detect and identify any seed-borne pathogenic fungi present, besides determining the pathogenicity and the seed damages. The fungi detected were Aspergillus niger, Fusarium oxysporum, Cercospora arachidicola, Rhizopus sp., Penicillium sp., Cladosporium sp. and Phoma sp.. The most frequently isolated fungi were Aspergillus niger and Penicillium sp.. These fungi were tra...

  2. Characterization and toxicity of Amanita cokeri extract.

    Science.gov (United States)

    Drehmel, Dennis C; Chilton, William Scott

    2002-02-01

    The nonprotein amino acids 2-amino-3-cyclopropylbutanoic acid and 2-amino-5-chloro-4-pentenoic acid were isolated from the mushroom Amanita cokeri. The cyclopropyl amino acid is toxic to the fungus Cercospora kikuchii, the arthropod Oncopeltus fasciatus (milk weed bug), and the bacteria Agrobacterium tumefaciens, Erwinia amylovora, and Xanthomonas campestris. Toxicity to bacteria was reversible by addition of isoleucine to the medium. No toxicity was observed for 2-amino-5-chloro-4-pentenoic acid.

  3. Potential biochemical markers for selection of disease resistance in Vigna radiata

    International Nuclear Information System (INIS)

    The Vigna radiata (L.) Wilczek (Green gram), a major pulse crop is prone to damaging diseases caused by Erysiphe polygoni, Cercospora canescens and Rhizoctonia sp. Therefore, the development of multiple resistance is a major breeding objective in green gram. Resistance to powdery mildew has already been developed, however, there are no reports on the development of resistance to Cercospora in green gram. Owing to limitation of conventional screening methods, the improvement for multiple disease resistance is inadequate, in this crop. It needs an efficient and quick selection method, for screening the plant population at an early stage. It is well established that the resistant interaction, in plants, involves accumulation of antibiotic compound phytoalexin (Genestein in Vigna radiata) and induction of enzymes such as β-1,3 gulcanase and Chitinases. These compounds are not only induced by pathogens but also pathogen-derived elicitors. These biochemical compounds can be used as resistance indicative biochemical markers for screening the natural or mutagen induced genetic diversity in populations of Vigna radiata in non-destructive manner. It, however, needs a systematic study of plant defense response. This paper deals with the response of resistant and susceptible cultivars of vigna radiata to Cercospora elicitor and development of non-destructive selection method for disease resistance. (author)

  4. Synthesis and Biological Activities of Novel Anthranilic Diamides Analogues Containing Benzo[b]thiophene

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-feng; LIU Chen; LIU Peng-fei; YAN Tao; WANG Bao-lei; XIONG Li-xia; LI Zheng-ming

    2013-01-01

    A series of novel anthranilic diamides analogues containing benzo[b]thiophenyl ring was designed and synthesized.Their structures were characterized by melting points,1H nuclear magnetic resonance(1H NMR) and high-resolution mass spectrometry(HRMS).The bioassay tests indicate that their insecticidal activities were weak to moderate.Antibacterial tests indicate that some of the compounds showed favourable activity in vitro against Physalospora piricola,Alternaria solani,Cercospora arachidicola,Gibberella sanbinetti and Phytophthora infestans at a dosage of 50 mg/L.

  5. Characterization of a new antifungal non-specific lipid transfer protein (nsLTP) from sugar beet leaves

    DEFF Research Database (Denmark)

    Kristensen, A K; Brunstedt, J; Madsen, M T;

    2000-01-01

    cysteines at conserved positions, the protein can be classified as a member of the plant family of non-specific lipid transfer proteins (nsLTPs). The protein is 47% identical to IWF1, an antifungal nsLTP previously isolated from leaves of sugar beet. A potential site for N-linked glycosylation present...... sequence of 26 amino acid residues. The protein shows a strong in vitro antifungal activity against Cercospora beticola (causal agent of leaf spot disease in sugar beet) and inhibits fungal growth at concentrations below 10 µg ml(-1)....

  6. 我国西部三省区丝孢菌新记录种%New records of Hphomycetes from western provinces in China

    Institute of Scientific and Technical Information of China (English)

    翟凤艳; 杨蕊; 刘英杰; 李玉

    2011-01-01

    报道了宁夏、云南和四川三个省区的8个丝孢菌新记录种,分别是宁夏回族自治区新记录种荞麦尾孢Cercospora fagopyri、轮纹尾孢C.zonata、仁果枝孢Cladosporium malorum、藜钉孢Passalora dubia、插天泡假尾孢Pseudocercospora rubi、稍厚柱隔孢Ramularia crassiuscula;云南省新记录种紫草柱隔孢R.cerinthes;四川省新记录种莴苣柱隔孢 R.lactucosa.

  7. 我国西部三省区丝孢菌新记录种

    Institute of Scientific and Technical Information of China (English)

    翟凤艳; 杨蕊; 刘英杰; 李玉

    2011-01-01

    报道了宁夏、云南和四川三个省区的8个丝孢菌新记录种,分别是宁夏回族自治区新记录种荞麦尾孢Cercospora fagopyri、轮纹尾孢C.zonata、仁果枝孢Cladosporium malorum、藜钉孢Passalora dubia、插天泡假尾孢Pseudocercospora rubi、稍厚柱隔孢Ramularia crassiuscula;云南省新记录种紫草柱隔孢R.cerinthes;四川省新记录种莴苣柱隔孢R.lactucosa.

  8. TRATAMENTO DE SEMENTES DE ARROZ, TRIGO, FEIJÃO E SOJA COM UM PRODUTO FORMULADO À BASE DE CÉLULAS E DE METABÓLITOS DE Bacillus subtilis

    OpenAIRE

    LAZZARETTI E; W. Bettiol

    1997-01-01

    Um produto constituido de pó-molhável (PBBS) formulado à base de células (60g) e de metabólitos (60g) de Bacillus subtilis, argila (480g), espalhante (7,92g) e água (2400ml), moído e seco, mostrou-se semelhante aos tratamentos com fungicidas recomendados para o controle de Rhizoctonia solani, Aspergillus sp. e Sclerotinia sclerotiorum em sementes de feijão; Pyricularia oryzae e Rhinchosporium sativum em sementes de arroz; e Cercospora kikuchii, Phomopsis phaseoli e Fusarium spp. em sementes d...

  9. BRS 153: cultivar de soja com boa adaptação ao sistema plantio direto no Rio Grande do Sul BRS 153: a soybean cultivar well-adapted to no-till in the State of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Emídio Rizzo Bonato

    2002-08-01

    Full Text Available A cultivar de soja BRS 153, oriunda do cruzamento EMBRAPA 1 x Braxton, é de ciclo médio, possui plantas de crescimento determinado, flor branca, pubescência cinza e grãos de hilo marromclaro. É resistente ao cancro-da-haste (Diaporthe phaseolorum f. sp. meridionalis, à podridão-parda-da-haste (Phialophora gregata, à mancha-olho-de-rã (Cercospora sojina e ao oídio (Microsphaera diffusa. O rendimento médio de grãos, em 19 ambientes do Rio Grande do Sul, foi 12% e 14% superior aos das cultivares RS 7-Jacuí e BR-16, respectivamente. É indicada para semeaduras em novembro, em todo o Rio Grande do Sul.Soybean cultivar BRS 153, derived from the cross EMBRAPA 1 x Braxton, has medium cycle and has determinate growth habit plants, with white flowers, gray pubescence, and light brown hilum. It is resistant to soybean stem canker (Diaporthe phaseolorum f. sp. meridionalis, brown stem rot (Phialophora gregata, frogeye leafspot (Cercospora sojina, and powdery mildew (Microsphaera diffusa. In 19 environments of the State of Rio Grande do Sul, Brazil, BRS 153 averaged 12% and 14% higher yields than cultivars RS 7-Jacuí and BR-16, respectively. It is indicated for sowing in November in all regions of Rio Grande do Sul.

  10. Pathogenicity of seed-borne and seedling fungi of groundnut cv. Tatu/ Patogenicidade de fungos associados às sementes e plântulas de amendoim cv. Tatu

    Directory of Open Access Journals (Sweden)

    Débora Cristina Santiago

    2005-06-01

    Full Text Available Seeds and seedlings of groundnut (Arachis hypogaea cv. Tatu were investigated under laboratory and green house conditions to detect and identify any seed-borne pathogenic fungi present, besides determining the pathogenicity and the seed damages. The fungi detected were Aspergillus niger, Fusarium oxysporum, Cercospora arachidicola, Rhizopus sp., Penicillium sp., Cladosporium sp. and Phoma sp.. The most frequently isolated fungi were Aspergillus niger and Penicillium sp.. These fungi were transmitted by seeds and caused damping-off before and after seedling emergence.Sementes e plântulas de amendoim (Arachis hypogaea cv. Tatu foram avaliadas em condições de laboratório e casa de vegetação com o objetivo de detectar e identificar a presença de fungos patogênicos associados às sementes, além de determinar a patogenicidade e os danos por eles causados. Os fungos detectados foram Aspergillus niger, Fusarium oxysporum, Cercospora arachidicola, Rhizopus sp., Penicillium sp., Cladosporium sp. e Phoma sp.. Os fungos mais freqüentes foram A. niger e Penicillium sp.. Estes fungos foram transmitidos através das sementes e causaram tombamento de pré e pósemergência nas plântulas.

  11. UFUS-Imperial: nova cultivar de soja para o Estado de Mato Grosso UFUS-Imperial: new soybean cultivar for the State of Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Osvaldo Toshiyuki Hamawaki

    2007-01-01

    Full Text Available A fim de ampliar as opções ao cultivo da soja, a Universidade Federal de Uberlândia lançou a cultivar UFUS-Imperial, proveniente do cruzamento entre (Msoy 8411xMsoy 8914 x (Emgopa 313xTucano. A cultivar apresentou resistência ao acamamento, à deiscência da vagem e aos patógenos: Fusarium solani, Cercospora sojina, Peronospora manshurica, Xanthomonas campestris pv. glycines e Diaporthe phaseolorum f.sp. meridionalis, e resistência parcial a Septoria glycines, Erysiphe diffusa e Phakopsora pachyrhizi. O rendimento dessa cultivar, em ensaios regionais, foi 45% superior ao da testemunha Msoy 6101, e é indicada para o Estado de Mato Grosso.With the purpose of offering new options for soybean production, the Universidade Federal de Uberlândia released the cultivar UFUS-Imperial, originated from the crosses between (Msoy 8411xMsoy 8914 x (Emgopa 313xTucano. It showed resistance to lodging, to pod shattering, and to the pathogens Fusarium solani, Cercospora sojina, Peronospora manshurica, Xanthomonas campestris pv. glycines and Diaporthe phaseolorum f.sp. meridionalis, and partial resistance to Septoria glycines, Erysiphe diffusa, and Phakopsora pachyrhizi. Its average yield from uniform trials was 45% higher than that of the control Msoy 6101, and it is indicated for cultivation in the State of Mato Grosso.

  12. Occurrence of fungal diseases on angelica (Archangelica officinalis Hoffm. in the region of Małopolska

    Directory of Open Access Journals (Sweden)

    Stanisław Mazur

    2012-12-01

    Full Text Available The field experiment on angelica (Archangelica officinalis Hoffm. was carried out in the years 2001-2002 at the plantations situated in Małopolska (Mydlniki near Kraków and Królówka near Bochnia. The results of two years' investigations pointed out, that angelica plants during vegetation were infested by many pathogens. The most often noticed on the plants were angelica rust (Puccinia anglicae, powdery mildew (Erysiphe umbelliferarum and Cercospora leaf spot (Cercospora sp.. Moreover, many various types of disease symptoms, which were described and made a diagnosis. There were mainly spots on leaves and steams, from which there were isolated most often fungi from Alternaria genus. The investigations on the salubrity of the seed material (angelica fruits coming from different sources showed that fungi from genus Alternaria were likely to transfer by seeds and caused disease symptoms on plants during vegetation. Fungi from genus Alternaria were most often isolated from angelica fruits. Saprotrophic fungi (Epicoccum purpurascens, Penicillium spp., Mucor hiemalis were also often isolated from angelica fruits. Disinfection on fruits reduced number of isolated fungi and bacteria.

  13. Soybean toxin (SBTX impairs fungal growth by interfering with molecular transport, carbohydrate/amino acid metabolism and drug/stress responses.

    Directory of Open Access Journals (Sweden)

    Janne K S Morais

    Full Text Available Soybean toxin (SBTX is an antifungal protein from soybeans with broad inhibitory activity against the growth and filamentation of many fungi, including human and plant pathogenic species such as Candida albicans, Candida parapsilosis, Aspergillus niger, Penicillium herquei, Cercospora sojina and Cercospora kikuchii. Understanding the mechanism by which SBTX acts on fungi and yeasts may contribute to the design of novel antifungal drugs and/or the development of transgenic plants resistant to pathogens. To this end, the polymorphic yeast C. albicans was chosen as a model organism and changes in the gene expression profile of strain SC5314 upon exposure to SBTX were examined. Genes that were differentially regulated in the presence of SBTX were involved in glucose transport and starvation-associated stress responses as well as in the control of both the induction and repression of C. albicans hyphal formation. Transmission electron microscopy showed that C. albicans cells exposed to SBTX displayed severe signs of starvation and were heavily granulated. Our data were indicative of C. albicans cell starvation despite sufficient nutrient availability in the medium; therefore, it can be speculated that SBTX blocks nutrient uptake systems. Because neither the starvation signal nor the alkaline response pathway lead to the induction of hyphae, we hypothesise that conflicting signals are transmitted to the complex regulatory network controlling morphogenesis, eventually preventing the filamentation signal from reaching a significant threshold.

  14. Soybean toxin (SBTX) impairs fungal growth by interfering with molecular transport, carbohydrate/amino acid metabolism and drug/stress responses.

    Science.gov (United States)

    Morais, Janne K S; Bader, Oliver; Weig, Michael; Oliveira, Jose Tadeu A; Arantes, Mariana R; Gomes, Valdirene M; Da Cunha, Maura; Oliveira, Hermogenes D; Sousa, Daniele O B; Lourencao, Andre L; Vasconcelos, Ilka M

    2013-01-01

    Soybean toxin (SBTX) is an antifungal protein from soybeans with broad inhibitory activity against the growth and filamentation of many fungi, including human and plant pathogenic species such as Candida albicans, Candida parapsilosis, Aspergillus niger, Penicillium herquei, Cercospora sojina and Cercospora kikuchii. Understanding the mechanism by which SBTX acts on fungi and yeasts may contribute to the design of novel antifungal drugs and/or the development of transgenic plants resistant to pathogens. To this end, the polymorphic yeast C. albicans was chosen as a model organism and changes in the gene expression profile of strain SC5314 upon exposure to SBTX were examined. Genes that were differentially regulated in the presence of SBTX were involved in glucose transport and starvation-associated stress responses as well as in the control of both the induction and repression of C. albicans hyphal formation. Transmission electron microscopy showed that C. albicans cells exposed to SBTX displayed severe signs of starvation and were heavily granulated. Our data were indicative of C. albicans cell starvation despite sufficient nutrient availability in the medium; therefore, it can be speculated that SBTX blocks nutrient uptake systems. Because neither the starvation signal nor the alkaline response pathway lead to the induction of hyphae, we hypothesise that conflicting signals are transmitted to the complex regulatory network controlling morphogenesis, eventually preventing the filamentation signal from reaching a significant threshold.

  15. Impact of Poultry Manure on Growth Behaviour, Black Sigatoka Disease Response and Yield Attributes of Two Plantain (Musa spp. AAB Genotypes

    Directory of Open Access Journals (Sweden)

    Aba, SC.

    2011-01-01

    Full Text Available La baisse de rendement en culture de plantain est un phénomène fréquent après quelques cycles de production; elle est due à de faibles niveaux de matière organique du sol et à une sensibilité accrue à des stress biotiques. L'utilisation de variétés améliorées est une option bon marché et respectueuse de l'environnement pour lutter contre les maladies des plantes, mais le maintien du rendement d'un nouveau cultivar en bananeraie nécessite une bonne gestion de la fertilité des sols qui pourrait être obtenue par une utilisation judicieuse de fumier de volaille. Les effets des trois doses [(0, 10 et 20 t.ha-1] de fumier de volaille décomposé sur la croissance, la réponse à la cercosporiose noire et le rendement de PITA 24' (un hybride de plantain et de son grand-parent maternel 'Mbi-Egome' (une banane plantain locale ont été évalués à Onne (Nigeria dans une station à fortes précipitations de l'IITA. L'expérience a été menée selon un dispositif split plot en blocs aléatoires complets. Les résultats ont montré que les deux clones étudiés avaient des variables de croissance similaires, sauf pour la surface foliaire et la teneur en chlorophylle. Malgré la sensibilité du génotype hybride à la cercosporiose foliaire d'origine atmosphérique, les données sur les composantes du rendement ont montré que 'PITA 24' produisait significativement plus de mains et de doigts par régime, un meilleur rendement du régime et un meilleur rendement végétatif global, toutefois, les deux génotypes ont présenté un schéma similaire pour la répartition de la biomasse. Les plants fumés ont eu un rendement significativement amélioré par rapport aux plants témoins, mais il y a eu un rendement moindre pour la dose de 20 t.ha-1. L'augmentation des doses d'engrais a réduit de plus de 30 jours le temps de récolte; de même, la taille des plants, le drageonnage, la teneur en chlorophylle des feuilles, l'indice des feuilles non

  16. Synthesis and antifungal activity of 2-hydroxy-4,5-methylenedioxyaryl ketones as analogues of kakuol.

    Science.gov (United States)

    Musso, Loana; Dallavalle, Sabrina; Merlini, Lucio; Farina, Gandolfina

    2010-04-01

    In a study aiming to determine the structural elements essential to the antifungal activity of kakuol, we synthesized a series of 2-hydroxy-4,5-methylenedioxyaryl ketones, and we assayed their in vitro antifungal activity. The most sensitive target organisms to the action of these class of compounds were Phytophthora infestans, Phytium ultimum, Cercospora beticola, Cladosporium cucumerinum, and Rhizoctonia solani. Most of the analogs showed a remarkable in vitro activity, and some of them appeared significantly more effective than the natural product. The biological activity was mainly affected by introducing structural modification on the carbonyl moiety of the natural-product molecule. In particular, compound 5a, bearing a C=C bond conjugated to the C=O group, was found active with a MIC value of 10 microg ml(-1) against Cladosporium cucumerinum. The results suggest that 2-hydroxy-4,5-methylenedioxyaryl ketones can be considered promising candidates in the development of new antifungal compounds. PMID:20397224

  17. Early detection and quantification of Ramularia beticola in sugar beets using spore traps and real-time PCR

    DEFF Research Database (Denmark)

    Wieczorek, Thies Marten; Justesen, Annemarie Fejer; Jørgensen, Lise Nistrup;

    2012-01-01

    used fungicide dose is recommended for each treatment. Preliminary field trials have indicated a more efficient control of fungal diseases and higher sugar yield if sugar beets are treated with fungicides before visual symptoms occur. For a better determination of the optimized timing of disease...... method to detect and to quantify R. beticola DNA in air samples obtained from Burkard® spore traps. Primers were designed based on the ITS region sequences and tested on R. beticola isolates from 2010 and 2011. The specificity of the primers was tested on related fungi, including Cercospora beticola...... and other Ramularia fungi. Real-time PCR was used to measure the quantity of the DNA of R. beticola collected on tapes from the Burkard Spore Traps®. Three spore traps were set up in sugar beet fields at three different sites on the Danish island of Lolland. Based on real-time PCR, R. beticola DNA...

  18. New Records of Hyphomycetes in Henan Province%河南丝孢菌新记录种

    Institute of Scientific and Technical Information of China (English)

    喻璋; 任国兰

    2006-01-01

    从河南各地采集的1 000多份真菌标本中,鉴定出丝孢菌类12属,54种.其中河南新记录种16个.即葡萄孢菌2种(Botrytis tulipor,B.squamosa);梨孢菌1种(Pyricularia gisea);尾孢菌3种(Cercospora ipomoeae,C.achyrunthina,C.mangiferae);黑孢菌2种(Nigrospora oryzae,N.sphaeriea);皮思孢菌1种(Pithomyces);弯孢菌3种(Curularia laonenosis,C.eragrosfidis,C.geniculata);德氏孢菌1种(Drechslera cynodontis);链格孢菌2种(Alternaria dianthi,A.dianthicola);匍柄孢菌1种(Stemphylium botrytosum).

  19. Cultivar de soja BRS 205

    Directory of Open Access Journals (Sweden)

    Bonato Emídio Rizzo

    2002-01-01

    Full Text Available A BRS 205, cultivar de soja de ciclo semiprecoce, obtida do cruzamento [BR-16(2 x Ocepar 8] x Tracy-M, é indicada para o Rio Grande do Sul, em semeaduras de novembro. Possui crescimento determinado, plantas de flor branca, pubescência marrom, porte baixo e grãos de hilo preto. Tem resistência ao cancro-da-haste (Diaporthe phaseolorum f. sp. meridionalis, à podridão-parda-da-haste (Phialophora gregata, à mancha-olho-de-rã (Cercospora sojina e à pústula bacteriana (Xanthomonas axonopodis pv. glycines. É moderadamente resistente ao oídio (Microsphaera diffusa. O rendimento médio de grãos foi 6% e 11% superior ao das cultivares RS 7-Jacuí e BR-16, respectivamente.

  20. Fungicide resistance assays for fungal plant pathogens.

    Science.gov (United States)

    Secor, Gary A; Rivera, Viviana V

    2012-01-01

    Fungicide resistance assays are useful to determine if a fungal pathogen has developed resistance to a fungicide used to manage the disease it causes. Laboratory assays are used to determine loss of sensitivity, or resistance, to a fungicide and can explain fungicide failures and for developing successful fungicide recommendations in the field. Laboratory assays for fungicide resistance are conducted by measuring reductions in growth or spore germination of fungi in the presence of fungicide, or by molecular procedures. This chapter describes two techniques for measuring fungicide resistance, using the sugarbeet leaf spot fungus Cercospora beticola as a model for the protocol. Two procedures are described for fungicides from two different classes; growth reduction for triazole (sterol demethylation inhibitor; DMI) fungicides, and inhibition of spore germination for quinone outside inhibitor (QoI) fungicides.

  1. Enzyme encapsulation in magnetic chitosan-Fe3O4 microparticles.

    Science.gov (United States)

    Costa-Silva, Tales Alexandre; Marques, Polyana Samorano; Souza, Cláudia Regina Fernandes; Said, Suraia; Oliveira, Wanderley Pereira

    2015-01-01

    Two simple procedures for the preparation of magnetic chitosan enzyme microparticles have been investigated and used for the immobilisation of endophytic fungus Cercospora kikuchii lipase as model enzyme. In the first case, lipase was entrapped in Fe3O4-chitosan microparticles by cross-linking method, while in the second case magnetic immobilised derivatives were produced using spray drying. Immobilised enzymes showed high enzyme activity retention and stability during storage without significant loss of activity. Glutaraldehyde Fe3O4-chitosan powders presented a higher lipase activity retention and storage stability than the others preparations. However, the immobilised derivatives produced by cross-linking showed higher enzyme activity after reuse cycles. The results proved that the magnetic Fe3O4-chitosan microparticles are an effective support for the enzyme immobilisation since the immobilised lipase showed best properties than the free form.

  2. Influence of He-Ne laser irradiation of soybean seeds on seed mycoflora, growth, nodulation, and resistance to Fusarium solani

    International Nuclear Information System (INIS)

    Laser irradiation of soybean seeds for 3 min caused a clear reduction in the number of seed-borne fungi which became more pronounced as the irradiation time was extended. Pretreatment of the seeds with methylene blue, methyl red and carmine enhanced the effect of laser. Rhizoctonia solani, Alternaria tenuissima, Cercospora kikuchii and Colletotrichum truncatum were completely eliminated when the seeds were pretreated with a dye and irradiated for 10 min. Seed germination was stimulated on exposure of the seed to 1-min irradiation. Chlorophyll a, chlorophyll b and carotenoid content of developed plants differed, depending on the irradiation dose and dye treatment of the seeds. The number and dry mass of nodules were mostly greater (as compared to the corresponding control), when the seeds irradiated for 1 or 3 min were pretreated with methyl red, chlorophenol red, crystal violet and methylene blue. Irradiation of pre-sowing seeds greatly protected soybean stands against F. solani

  3. Environmental Factors in the Growth of Jatropha at Potorono Village, Yogyakarta

    Directory of Open Access Journals (Sweden)

    Mohammad Nurcholis

    2015-01-01

    Full Text Available Jatropha curcas is a perennial crop that has been known by Indonesian people for more than seven decades as a plant that produces renewable biofuel. In the present decade, plants producing biofuel are expected to be developed to overcome the lowering nonrenewable fuel reserves. There is a myth that jatropha can grow well on marginal lands and draught condition, perform well on non-fertile soils, no need for agronomic management and is resistant to plant pests and diseases. This study was conducted to identify the environmental factors that influenced the growth of jatropha on the marginal land at Potorono village, Yogyakarta Province, Indonesia. Jatropha has been planted by local people at the village road sides and on the marginal land field at the local governmental land in this village. They grew jatropha on these areas with the purpose of preventing competition of area utilization with food crops. The results showed that the growth of jatropha was restricted by low content of organic matter, plant nutrition and poor soil drainage. Applications of manure and macro nutrients (N, P and K to this crop were able to increase crop performance. The number of shoots, flowers and fruit bunches increased by manure and nutrients treatments. Field observation showed that there were several plant pests, such as Aspidiotus sp., Paracoccus marginatus, Poliphagotarsonemus latus, Selenothrips rubrocinctus, Chrysochoris javanus, Valanga nigricornis, Chloracris prasina, and Helicoverpa armigera that attacked plant leaves and fruits. There were plant leaf necrotic symptoms that caused by plant pathogens were also observed. The diseases are bacterial leaf spot (Xanthomonas ricinicola, cercospora leaf spot (Cercospora ricinella and rust (Phakopsora jatrophicola. Thus, jatropha is like any other plants that need a good agro-ecological condition to grow well and produce high yield.

  4. Breeding of improved grain legume genotypes for Bangladesh through nuclear and conventional techniques

    International Nuclear Information System (INIS)

    Grain legumes are important in Bangladesh for human diet, as cattle feed, for cropping pattern and soil fertility. But their production has been steadily declining owing to severe competition from cereals. Development of improved genotypes is problematic because of the lack of adequate genetic variability in these legumes. Mutation breeding programmes on chickpea (Cicer arietinum L.), mungbean (Vigna radiata (L.) Wilczek) and blackgram (Vigna mungo (L.) Hepper) were therefore attempted in order to create adequate variability and later selection of mutans. Adaptability studies with exotic genotypes were also carried out. In chick-pea, one high yielding, high protein variety named Hyprosola, with 20% higher yield and 4% increased protein per unit seed weight, has been released from the gamma irradiated material. Three mutants and one exotic germplasm with higher yield and desirable agronomic characters are in advanced stages of development. Sodium azide treatment has resulted in isolation and development of genotypes with an increased number of pods/plant and higher seed yield. Gamma irradiation of mungbean has yielded mutants with 15-17% higher yield and resistance/tolerance to mungbean yellow mosaic virus (MYMV) and Cercospora leaf spot diseases. These are ready for release. Mutants with erect growth habit and synchrony in pod maturity were selected from the sodium azide treated population. Adaptation studies of the exotic and local germplasm have resulted in identification of genotypes suitable for growing during various seasons of the year. It has been possible to isolate and develop one blackgram mutant through irradiation with 15% higher seed yield and tolerance/resistance to Cercospora leaf spot disease and yellow mosaic virus (YMV). 41 refs, 1 fig., 17 tabs

  5. Severidade da mela da soja causada por Rhizoctonia solani AG-1 IA em função de doses de potássio Severity of hte foliar blight of the soylean caused by Rhizoctonia solani AG-1 IA infunction of doses of potassium

    Directory of Open Access Journals (Sweden)

    Marco Antonio Basseto

    2007-03-01

    Full Text Available O fungo Rhizoctonia solani pertencente ao grupo de anastomose 1 IA (AG-1 IA é um dos patógenos mais importantes afetando a cultura da soja no Brasil. Este fungo causa queima da folha e/ou mela em soja, para a qual medidas de manejo cultural são consideradas alternativas importantes para controle antes do estabelecimento da doença. Há evidências de que a adubação potássica diminui substancialmente a severidade dos sintomas de várias doenças da soja como a queima foliar (Cercospora kikuchii, a seca da haste e da vagem (Phomopsis phaseoli var. sojae e o cancro da haste (Diaporthe phaseolorum f. sp. meridionalis. Apesar das evidências do efeito do potássio no controle de várias doenças da soja, não há informação na literatura sobre o efeito desse nutriente no controle da mela. A hipótese testada foi que a mela da soja pode ser controlada através de incrementos na adubação potássica. De maneira geral, concluiu-se que, sob condições de casa de vegetação, o incremento de K no solo não resultou no controle da mela da soja. É necessário, entretanto, confirmar esta observação conduzindo-se experimentos sob condições de campo, podendo-se incluir a avaliação do efeito da doença sob aspectos da produção.The fungus Rhizoctonia solani, belonging to anastomosis group 1IA (AG-1 IA is one of the most important pathogens affecting soybean in Brazil. This fungus causes aerial or foliar blight of soybean, and cultural measures are thought as important choices for the control before the establishment of the disease. Based on evidences that potassium amendments can substantially reduce the severity of several soybean diseases such as Cercospora leaf blight (Cercospora kikuchii, pod and stem blight (Phomopsis phaseoli var. sojae and stem canker (Diaporthe phaseolorum f. sp. meridionalis. Despite all evidence, there is no information in the literature about the effect of potassium controlling the soybean foliar blight. The

  6. Survival of pathogens on soybean debris under no-tillage and conventional tillage systems Sobrevivência de patógenos em restos de cultura de soja mantidos em sistema de semeadura direta e convencional

    Directory of Open Access Journals (Sweden)

    Álvaro Manuel Rodrigues Almeida

    2001-10-01

    Full Text Available A study was conducted in the subtropical area of Southern Brazil to determine the survival of pathogens in soybean residues under conventional and no-tillage cultivation systems from March to September of 1998 and 1999. The pathogens most frequently isolated were Colletotrichum truncatum, Phomopsis spp., Cercospora kikuchii, Fusarium spp., Macrophomina phaseolina, and Rhizoctonia solani. Other fungi isolated were Myrothecium roridum, Penicillium sp., Chaetomium sp., Epicoccum sp., Corynespora cassiicola and Trichoderma sp. The percent of survival of each pathogen varied according to the month and the year. Survival of C. truncatum, Phomopsis spp. and C. kikuchii were significantly reduced (pAvaliou-se a sobrevivência de patógenos em restos de soja, em sistema de semeadura direta e convencional, entre março e setembro de 1998 e 1999, em Londrina, PR. Os patógenos mais freqüentemente isolados foram Colletotrichum truncatum, Phomopsis spp., Cercospora kikuchii, Fusarium spp., Macrophomina phaseolina e Rhizoctonia solani. Outros fungos isolados foram Myrothecium roridum, Penicillium sp., Chaetomium sp., Epicoccum sp., Corynespora cassiicola e Trichoderma sp. A porcentagem de sobrevivência variou com o mês e o ano. A sobrevivência de C. truncatum, Phomopsis spp. e C. kikuchii foi significativamente reduzida (P<0,05 entre a primeira e última avaliação nos resíduos mantidos sobre ou sob o solo. M. phaseolina e Fusarium spp. não foram afetados, ou foram favorecidos pelo enterro dos resíduos. A freqüência de isolamento de Fusarium spp. aumentou em resíduos enterrados no solo. A perda de biomassa mostrou redução de 44,4% no sistema convencional e 34,9% no sistema de semeadura direta, em 1998, quando a distribuição de chuvas foi mais regular. Em 1999, a redução foi de 48,2% e 39,0% para os sistemas convencional e de semeadura direta, respectivamente.

  7. Resistance to gray leaf spot of maize: genetic architecture and mechanisms elucidated through nested association mapping and near-isogenic line analysis.

    Directory of Open Access Journals (Sweden)

    Jacqueline M Benson

    2015-03-01

    Full Text Available Gray leaf spot (GLS, caused by Cercospora zeae-maydis and Cercospora zeina, is one of the most important diseases of maize worldwide. The pathogen has a necrotrophic lifestyle and no major genes are known for GLS. Quantitative resistance, although poorly understood, is important for GLS management. We used genetic mapping to refine understanding of the genetic architecture of GLS resistance and to develop hypotheses regarding the mechanisms underlying quantitative disease resistance (QDR loci. Nested association mapping (NAM was used to identify 16 quantitative trait loci (QTL for QDR to GLS, including seven novel QTL, each of which demonstrated allelic series with significant effects above and below the magnitude of the B73 reference allele. Alleles at three QTL, qGLS1.04, qGLS2.09, and qGLS4.05, conferred disease reductions of greater than 10%. Interactions between loci were detected for three pairs of loci, including an interaction between iqGLS4.05 and qGLS7.03. Near-isogenic lines (NILs were developed to confirm and fine-map three of the 16 QTL, and to develop hypotheses regarding mechanisms of resistance. qGLS1.04 was fine-mapped from an interval of 27.0 Mb to two intervals of 6.5 Mb and 5.2 Mb, consistent with the hypothesis that multiple genes underlie highly significant QTL identified by NAM. qGLS2.09, which was also associated with maturity (days to anthesis and with resistance to southern leaf blight, was narrowed to a 4-Mb interval. The distance between major leaf veins was strongly associated with resistance to GLS at qGLS4.05. NILs for qGLS1.04 were treated with the C. zeae-maydis toxin cercosporin to test the role of host-specific toxin in QDR. Cercosporin exposure increased expression of a putative flavin-monooxygenase (FMO gene, a candidate detoxification-related gene underlying qGLS1.04. This integrated approach to confirming QTL and characterizing the potential underlying mechanisms advances the understanding of QDR and will

  8. Influência do espaçamento e população de plantas sobre doenças de final de ciclo e oídio e caracteres agronômicos em soja = Influence of row spacing and plant population on late season disease severity, powdery mildew and agronomic characters in soybean

    Directory of Open Access Journals (Sweden)

    Jorge Luiz Knebel

    2006-07-01

    Full Text Available Este trabalho foi conduzido em Cascavel, Estado do Paraná, na safra de2004/2005, utilizando a cultivar de soja CD 202, para avaliar a influência do espaçamento e da população de plantas sobre a severidade de (DFC doenças de final de ciclo (Septoria glycines e Cercospora kikuchii e oídio da soja (Microsphaera diffusa e caracteres agronômicos da cultura. Os tratamentos foram 3 espaçamentos (22,5; 45,0 e 67,5 cm e 3 populações (200; 400; e 600 mil plantas ha-1. As DFC tiveram menor severidade no espaçamento reduzido e na população mais baixa, enquanto a ocorrência de oídio não se alterou. Em todos os espa��amentos, quanto maior a população de plantas, maior a altura final e, conseqüentemente, maior o acamamento de plantas. O número de legumes/planta foi superior no maior espaçamento e reduziu com o aumento da população; o número de grãos/planta diminuiu com o aumento da população; e a produtividade foi superior no menor espaçamento.This study was carried out in Cascavel, Paraná State, during the growing season 2004/2005, using soybean cultivar CD 202. The aim was to evaluate the influence of row-spacing and plant population on lateseason disease severity (Septoria glycines and Cercospora kikuchii, soybean powdery mildew (Microsphaera diffusa and agronomic characters of the culture. The treatments were three row spacing (22.5; 45.0 and 67.5 cm and three plant populations (200; 400; and 600 thousand plants ha-1. Late season disease had smaller severity in the reduced spacing and in the lowest population, while the powdery mildew occurrence did not modify with these factors. In all spacing, as larger the plants density, larger the plants height and consequently larger the plants fallen. The number pods per plant was higher with the largest spacing and it decreased with the population increase; the number of grains per plant decreased with the population increase; and the productivity was higher in the smallest spacing.

  9. Ocorrência de fungos em sementes de soja produzidas sob calagem e adubação potássica residuais The residual effect of liming and potassium fertilization on the occurrence of fungi in soybean seeds

    Directory of Open Access Journals (Sweden)

    H.A.A. Mascarenhas

    1995-12-01

    Full Text Available Estudou-se o efeito residual da adubação potássica e da calagem sobre a ocorrência de fungos em sementes de soja. O experimento foi instalado com a cultivar IAC-17, no ano agrícola de 1991/92, aplicando doses a lanço de O, 3,5 e 7 t/ha de calcário dolomítico e de 0, 150, 300, 450 e 600 kg/ha de K2O. As sementes colhidas no terceiro ano de cultivo, (1993/94 foram submetidas ao teste de sanidade, pelo método do papel de filtro. Observou-se que a calagem reduziu significativamente a incidência de Phomopsis sp., favorecendo, no entanto, a presença de Aspergillus sp. e de Fusarium sp.. Embora não tenham sido detectadas diferenças significativas, nos tratamentos com calagem, verificou-se redução da incidência de Cercospora kikuchii, Colltotrichum dematium var. truncata e Peronospora manshurica. Apenas a incidência de Phomopsis sp. diminuiu significativamente devido à adubação potássica, sendo menor quando se utilizou a dose de 450 kg/ha de K2O.To study the residual effect of liming and potassium fertilizer on the occurrence of fungi in soybean seeds, an experiment was installed during the 1991/92 growing season, using 0, 3.5 and 7.0 t/ha of dolomitic lime and 0, 150, 300, 450 and 600 kg/ha of K2O in the form of potassium cloride. In 1993/94 (the third year, the harvested seeds were submitted to a seed health test (blotter method. The results showed that liming reduced significantly the incidence of Phomopsis sp. and increased the presence of Aspergillus sp. and Fusarium sp.. Although no significant differences were observed with liming, there was a reduction in the incidence of Cercospora kikuchii, Colletotrichum dematium var. truncala and Peronospora manshurica. Among the fungi found in the seeds, only Phomopsis sp. was significantly reduced by potassium fertilization, the least incidence being observed at the rate of 450 kg/ha.

  10. Fenton reagent and titanium dioxide nanoparticles as antifungal agents to control leaf spot of sugar beet under field conditions

    Directory of Open Access Journals (Sweden)

    Hamza Amany

    2016-07-01

    Full Text Available In this study, foliar sprays of Fenton solutions (Fenton reaction, Fenton-like reaction and Fenton complex, titanium dioxide (TiO2 and the recommended fungicide (chlorothalonil were estimated in the control of sugar beet leaf spot caused by Cercospora beticola under field conditions in two growing seasons. In addition, the impacts of these treatments on some crop characters (leaf dry weight, root fresh weight, soluble solid content, sucrose content and purity of sugar were examined. Biochemical and histological changes in the livers and kidneys of treated rats compared to an untreated control were utilized to assess the toxicity of the examined curative agents. Overall, chlorothalonil and Fenton complex were the most effective treatments for disease suppression in both tested seasons followed by Fenton-like reagent, Fenton’s reagent and TiO2, respectively. Growth and yield characters of treated sugar beet significantly increased in comparison to an untreated control. There were mild or no (biochemical and histological changes in the livers and kidneys of treated rats compared to the control. Fenton solutions and TiO2 may offer a new alternative for leaf spot control in sugar beet.

  11. Synthesis, Bioactivities and Structure Activity Relationship of N-4-Methyl-1,2,3-thiadiazole-5-carbonyl-N'.phenyl Ureas%Synthesis, Bioactivities and Structure Activity Relationship of N-4-Methyl-1,2,3-thiadiazole-5-carbonyl-N'.phenyl Ureas

    Institute of Scientific and Technical Information of China (English)

    国丹丹; 王治文; 范志金; 赵晖; 张薇; 程家高; 杨家强; 吴青君; 张友军; 范谦; 无

    2012-01-01

    Twenty nine novel N-4-methyl-1,2,3-thiadiazole-5-carbonyl-N'-phenyl ureas were designed and synthesized, and their structures were confirmed by proton nuclear magnetic resonance (1H NMR), infra red spectroscopy (IR) and high-resolution mass spectroscopy (HRMS). Compounds V-9, V-11, V-12, V-15, V-19, V-21, V-22 and V-24 exhibit excellent activity against Culex pipiens pallens. Compounds V-12 and V-22 present good insecticidal activity against Plutella xylostella L. Their median lethal concentrations (LC50) are 164.15 and 89.69 mg-L^-1, respec- tively. Compound V-11 also has potential wide spectrum of fungicide activity. Its median effective concentrations (ECs0) detected from 3.82 μg·mL 1 against Physalospora piricola to 31.60 μg·mL-i against Cercospora arachidi- cola. Compounds V-15 and V-24 show outstanding induction activities as same as positive controls TDL and ning- nanmycin, furthermore V-24 has the highest induction activity of 41.85%±4.43%. To elucidate the structure activity relationship in these compounds, a 3D-QSAR model has been built. The established model showed a reliable predicting ability with q2 values of 0.643 and r2 values of 0.982.

  12. Inventory of Green Spaces and Woody Plants in the Urban Landscape in Ariogala

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    Lina Straigytė

    2012-12-01

    Full Text Available Background and Purpose: Regulation of urban greenery design, management and protection was approved in 2008 in Lithuania after the Green Space Law was passed, allowing protection of public green spaces and woody plants. Protection of these resources first requires an inventory, and we have created a digital database that will help in management of urban green spaces. Material and Methods: An inventory of green spaces and woody plants was conducted in the public urban territory of Ariogala, using GIS technology. A digital cartographic database was created using ArcGis 9.1 software. Results and Conclusion: Most of the woody plants in the survey area are deciduous trees, and the survey results highlighted the major green space management problems. Often, planted trees grow under power lines, and their crowns touch the power cables. Near blocks of flats, trees are often in the wrong place-planted too close to buildings, trees shade windows and their roots heave pavers and penetrate building foundations. According to the inventory, street trees sustain the most damage, most commonly showing injuries on their trunks and roots. Leaves of Aesculus hipocastanum L. show massive damage from Cameraria ohridella Deschka & Dimić, and Tilia cordata Mill. are damaged by Cercospora microsora Sacc. T. cordata is a favourite city tree, but is susceptible to infestation and when damaged appears unsightly, ending its vegetation period very early. The inventory of green spaces also showed that there are sufficient public parks.

  13. Study on Relativity Between Population of Nematode Crowd in Rhizosphere of Cryptomeria fortunei and Pestalotiopsis apiculatus%柳杉根际线虫群体数量与柳杉赤枯病的相关性研究

    Institute of Scientific and Technical Information of China (English)

    王邵军; 刘勇; 蔡秋锦; 彭九生

    2004-01-01

    于2002~2003年间,发现福建农林大学南平校区柳杉绿化林带有严重病害发生,经过病原鉴定为柳杉赤枯病(Cercospora secoiae).同时,从柳杉病区林木根系及根际土壤分离到大量双宫螺旋线虫(Helicotylenchus Dihystera)、马丁矮化线虫(Tylencnchorhynchus martini)、肾形肾脏线虫(Rotylenchulus reniformis)、微小针线虫(Paratylenchus minuts)、垫刃线虫(Tylenchus platycephalus)及一定量的盘旋线虫(Rotylenchus caudnphasmidius)、美洲剑线虫(Xiphinema americanum)、长针线虫未定种(Longidorus sp.)、尾滑刃线虫(Aphelenchoides composticola)、环线虫未定种(Macroposthonia sp.)、昏暗毛刺线虫(Trichdorus obscurus)、燕麦真滑线虫(Aphelenchus avenoe).根据相关性分析和有关报道,认为柳杉根际线虫某些类群的群体数量与柳杉赤枯病的发生有明显的相关性.

  14. Discrimination of Five Citrus Diseased Leaves by FTIR Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Xingxiang; ZHAO; Gang; LIU; Weixing; LI; Xiaohua; Wang; Jianming; HAO; Xiangping; ZHOU

    2014-01-01

    In this paper,citrus brown spot,huanglongbing,canker,fuliginous,Cercospora sp. and healthy leaves were studied using Fourier transform infrared spectroscopy( FTIR) combined with statistical analysis. The results showed that the spectra of the samples were similar,whereas there were obvious differences in the second derivatives of infrared spectra in the range of 1 500- 700 cm- 1. The correlative analysis were evaluated,results showed that the correlation coefficients were larger than 0. 918 between healthy leaves,and between the same diseased leaves. However,the values were all decreased between healthy and diseased leaves,and among different diseased leaves. The preprocessed original,first derivative and second derivative spectra in the range of 1 200- 700 cm- 1were chosen to evaluated principal component analysis( PCA) and hierarchical cluster analysis( HCA),respectively. The performance of the overall accuracy of PCA was 92.5%,which were better than original dataset and first derivative dataset. HCA by selecting second derivative dataset yield about 90% accuracy. This study proved that FTIR spectroscopy could be detected citrus diseases quickly and accurately.

  15. Cercosporoid diseases of Citrus.

    Science.gov (United States)

    Huang, Feng; Groenewald, J Z; Zhu, Li; Crous, P W; Li, Hongye

    2015-01-01

    Citrus leaves and fruits exhibiting disease symptoms ranging from greasy spot, yellow spot, small or large brown spot, black dot, and brown dot were sampled from Fujian, Guangdong, Guizhou, Hunan, Jiangxi, Yunnan, Zhejiang provinces and the Guangxi Zhuang Autonomous Region in China. In total 82 isolates representing various cercosporoid genera were isolated from these disease symptoms, which were supplemented with eight Citrus cercosporoid isolates collected from other countries. Based on a morphological and phylogenetic study using sequence data from the nuclear ribosomal DNA's ITS1-5.8S-ITS2 regions (ITS), and partial actin (act), β-tubulin (tub2), 28S nuclear ribosomal RNA (28S rDNA) and translation elongation factor 1-α (tef1) genes, these strains were placed in the following genera: Cercospora, Pallidocercospora, Passalora, Pseudocercospora, Verrucisporota and Zasmidium. All isolates tended to be sterile, except the Zasmidium isolates associated with citrus greasy spot-like symptoms, which subsequently were compared with phylogenetically similar isolates occurring on Citrus and other hosts elsewhere. From these results four Zasmidium species were recognized on Citrus, namely Z. indonesianum on Citrus in Indonesia, Z. fructicola and Z. fructigenum on Citrus in China and Z. citri-griseum, which appears to have a wide host range including Acacia, Citrus, Eucalyptus and Musa, as well as a global distribution.

  16. Genetic characterization and linkage disequilibrium mapping of resistance to gray leaf spot in maize(Zea mays L.)

    Institute of Scientific and Technical Information of China (English)

    Liyu; Shi; Xiangling; Lv; Jianfeng; Weng; Hanyong; Zhu; Changlin; Liu; Zhuanfang; Hao; Yu; Zhou; Degui; Zhang; Mingshun; Li; Xiaoke; Ci; Xinhai; Li; Shihuang; Zhang

    2014-01-01

    Gray leaf spot(GLS),caused by Cercospora zeae-maydis,is an important foliar disease of maize(Zea mays L.)worldwide,resistance to which is controlled by multiple quantitative trait loci(QTL).To gain insights into the genetic architecture underlying the resistance to this disease,an association mapping population consisting of 161 inbred lines was evaluated for resistance to GLS in a plant pathology nursery at Shenyang in 2010 and 2011.Subsequently,a genome-wide association study,using 41,101 single-nucleotide polymorphisms(SNPs),identified 51 SNPs significantly(P<0.001)associated with GLS resistance,which could be converted into 31 QTL.In addition,three candidate genes related to plant defense were identified,including nucleotidebinding-site/leucine-rich repeat,receptor-like kinase genes similar to those involved in basal defense.Two genic SNPs,PZE-103142893 and PZE-109119001,associated with GLS resistance in chromosome bins 3.07 and 9.07,can be used for marker-assisted selection(MAS)of GLS resistance.These results provide an important resource for developing molecular markers closely linked with the target trait,enhancing breeding efficiency.

  17. Behaviour of the efficiency in six rice materials of short cycle against fungosas illness.

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    Ridelmis Rodríguez Hernández

    2010-04-01

    Full Text Available During 2005 till 2006 and 2006 till 2007.dry seasons and 2007 Wet Seasons, a plot experiment was carried out at the Rice Experimental Station “ Sur del Jíbaro”, in Sancti- Spíritus, in order to know the response of four short duration rice varieties (LP-5, IACuba 31, Reforma and two genetic lines (4561 and 4697 to Spotted Grain Diseases and yield of rice in these conditions. The experiment was directed dry seeded at a distance of 15 centimeters between rows. A complete block design was used, composed of six treatments and four replications in a Vertisol, typical of cuban rice soils. Highest yields were obtained by Reforma and IACuba 31 varieties in both seasons: 5.23 and 5.00 t/ha in Dry Seasons and 4.50 each variety in Wet Seasons, respectively. All the varieties and lines testd showed their resistance, not only to Spotted Grain Diseases, but also to Pyricularia grisea, Cercospora oryzae. Highest income was obtained by the variety Reforma (2 512 USD/ha and 2 160 USD/ha, during Dry and Wet Seasons, respectively. By the other side, line 4 697 obtained the lowest incame (1 584 and 1 472 USD/ha in Dry and Wet Seasons, respectively.

  18. Detection of Disease Symptoms on Hyperspectral 3d Plant Models

    Science.gov (United States)

    Roscher, Ribana; Behmann, Jan; Mahlein, Anne-Katrin; Dupuis, Jan; Kuhlmann, Heiner; Plümer, Lutz

    2016-06-01

    We analyze the benefit of combining hyperspectral images information with 3D geometry information for the detection of Cercospora leaf spot disease symptoms on sugar beet plants. Besides commonly used one-class Support Vector Machines, we utilize an unsupervised sparse representation-based approach with group sparsity prior. Geometry information is incorporated by representing each sample of interest with an inclination-sorted dictionary, which can be seen as an 1D topographic dictionary. We compare this approach with a sparse representation based approach without geometry information and One-Class Support Vector Machines. One-Class Support Vector Machines are applied to hyperspectral data without geometry information as well as to hyperspectral images with additional pixelwise inclination information. Our results show a gain in accuracy when using geometry information beside spectral information regardless of the used approach. However, both methods have different demands on the data when applied to new test data sets. One-Class Support Vector Machines require full inclination information on test and training data whereas the topographic dictionary approach only need spectral information for reconstruction of test data once the dictionary is build by spectra with inclination.

  19. PHYSIC NUT ( JATROPHA CURCAS L. DISEASES IN LAMPUNG PROVINCE

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    TRI MARYONO

    2009-01-01

    Full Text Available Intensifi ed cultivation of physic nut (Jatropha curcas L. could raise the importance of plant diseases. h e objectives of this research were to diagnose diseases occurring on physic nut in Lampung Province and to determine their intensity. Field observation was conducted in four districts: South Lampung, Tanggamus, Bandarlampung, and Tulang Bawang. Disease intensity, whether expressed as disease incidence or severity, was recorded from plant samples determined by making diagonal lines across the fi eld on which fi ve observation spots were made. On each spot, fi ve plant samples were observed. Specimens were also collected and placed individually in plastic bags for laboratory observation. h e diseases found on physic nut in Lampung Province were cercospora leaf spot, alternaria leaf spot, fusarium wilt, and bacterial wilt. In addition, leaf malformation fi rst thought to be viral disease was commonly found in many locations. Further mechanical transmission failed to produce similar symptom on tested plants and higher population of mites were found on malformed leaves than that in normal leaves. Based on the disease distribution and intensity, the most likely threatening disease in physic nut cultivation is bacterial wilt. Fusarium also caused wilt, but it was only found in one subdistrict with low incidence.

  20. BRS 137: cultivar de soja para cultivo no Sul do Brasil

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    Bonato Emídio Rizzo

    2001-01-01

    Full Text Available A liberação de cultivares de elevado potencial produtivo e com resistência a doenças é fundamental para continuar agregando rendimento na produção brasileira de soja. A cultivar BRS 137 é resultado do programa de melhoramento de soja desenvolvido pela Embrapa. A cultivar apresentou rendimento médio de grãos 2% superior ao da cultivar IAS 5, em 24 ambientes, no Rio Grande do Sul. É resistente à pústula-bacteriana (Xanthomonas axonopodis pv. glycines, ao cancro-da-haste (Diaporthe phaseolorum f. sp. meridionalis, à podridão-parda-da-haste (Phialophora gregata, à mancha-olho-de-rã (Cercospora sojina e ao oídio (Microsphaera diffusa. É indicada para cultivo no Rio Grande do Sul, em semeaduras realizadas a partir de meados de outubro até fim de novembro, com população máxima de 300.000 plantas/ha.

  1. TRATAMENTO DE SEMENTES DE ARROZ, TRIGO, FEIJÃO E SOJA COM UM PRODUTO FORMULADO À BASE DE CÉLULAS E DE METABÓLITOS DE Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    LAZZARETTI E

    1997-01-01

    Full Text Available Um produto constituido de pó-molhável (PBBS formulado à base de células (60g e de metabólitos (60g de Bacillus subtilis, argila (480g, espalhante (7,92g e água (2400ml, moído e seco, mostrou-se semelhante aos tratamentos com fungicidas recomendados para o controle de Rhizoctonia solani, Aspergillus sp. e Sclerotinia sclerotiorum em sementes de feijão; Pyricularia oryzae e Rhinchosporium sativum em sementes de arroz; e Cercospora kikuchii, Phomopsis phaseoli e Fusarium spp. em sementes de soja. Para Dreschlera oryzae em arroz e Bipolaris sorokiniana, P. oryzae e Alternaria tenuis em sementes de trigo, o tratamento com o PBBS, embora não tenha se igualado ao tratamento com o fungicida padrão, diferiu estatisticamente do tratamento testemunha. A nodulação das raízes de feijão e soja por bactérias simbióticas, fixadoras de nitrogênio, não foi influenciada quando o PBBS foi aplicado simultaneamente ao inoculante contendo Rhyzobium sp. e Bradyrhizobium japonicum, respectivamente. O PBBS também não afetou a emergência das plântulas das culturas testadas.

  2. Effect of Maize Hybrid and Foliar Fungicides on Yield Under Low Foliar Disease Severity Conditions.

    Science.gov (United States)

    Mallowa, Sally O; Esker, Paul D; Paul, Pierce A; Bradley, Carl A; Chapara, Venkata R; Conley, Shawn P; Robertson, Alison E

    2015-08-01

    Foliar fungicide use in the U.S. Corn Belt increased in the last decade; however, questions persist pertaining to its value and sustainability. Multistate field trials were established from 2010 to 2012 in Illinois, Iowa, Ohio, and Wisconsin to examine how hybrid and foliar fungicide influenced disease intensity and yield. The experimental design was in a split-split plot with main plots consisting of hybrids varying in resistance to gray leaf spot (caused by Cercospora zeae-maydis) and northern corn leaf blight (caused by Setosphaera turcica), subplots corresponding to four application timings of the fungicide pyraclostrobin, and sub-subplots represented by inoculations with either C. zeae-maydis, S. turcica, or both at two vegetative growth stages. Fungicide application (VT/R1) significantly reduced total disease severity relative to the control in five of eight site-years (Pfungicide-treated in three site-years. Fungicide application increased the yield by approximately 6% at Ohio in 2010, 5% at Wisconsin in 2010 and 6% in 2011. Yield differences ranged from 8,403 to 8,890 kg/ha in Wisconsin 2011 to 11,362 to 11,919 kg/ha in Wisconsin 2010. Results suggest susceptibility to disease and prevailing environment are important drivers of observed differences. Yield increases as a result of the physiological benefits of plant health benefits under low disease were not consistent.

  3. Diallel analyze of yield and progress of the severity of leaf diseases in maize hybrids in two population density

    Directory of Open Access Journals (Sweden)

    Marcos Ventura Faria

    2015-02-01

    Full Text Available Seven commercial maize hybrids (AS1575, 2B688, Penta, GNZ2004, AG8021, Sprint e P30F53 were intercrossed in a complete diallel, excluded reciprocal, obtaining 21 crosses. The 28 treatments were evaluated in two environments characterized by different densities (62,500 and 90,000 plants ha-1, with the aim of selecting the most promising parents for generating base population to obtain lines. Two experiments were carried out in Guarapuava-PR, at randomized block design with three replications. We estimated the general (GCA and specific (SCA combining abilities for yield and disease severity assessed by the area under the common rust (Puccinia sorghi progress curve (AURPC and the area under the leaf spot (Cercospora zeae-maydis progress curve (AULPC. The effects of GCA and SCA were significant for grain yield and diseases severity in both densities, revealing the importance of both additive and non-additive effects. There GCA x densities interaction was significant only for grain yield. Crossings P30F53 x AG8021 and P30F53 x Penta had negative estimates of SCA for AURPC and AULPC on the environments average. Hybrids GNZ 2004 and P30F53 stood out showing positive GCA for grain yield and negative for AURPC and AULPC in both densities and therefore are recommended for generating base populations for obtaining lines adapted for both densities, conventional and denser plantings, given the current trends in management of maize.

  4. Genetic mapping of resistance to purple seed stain in PI 80837 soybean.

    Science.gov (United States)

    Jackson, Eric Wayne; Feng, Chunda; Fenn, Patrick; Chen, Pengiun

    2008-01-01

    Purple seed stain (PSS) of soybean caused by Cercospora kikuchii is an important disease that reduces market grade and can affect seed germination and vigor. A single dominant gene was shown to confer PSS resistance in PI 80837. The objective of this research was to map the PSS resistance gene in PI 80837 using simple sequence repeat (SSR) markers. A cross was made between the PSS-susceptible cultivar Agripro 350 (AP 350) and PI 80837. The F2 population and parents were grown in the field, and the resistance or susceptibility of individual plants was determined by assaying the seed for infection by C. kikuchii. DNA of parent and F2 plants was extracted for SSR analysis and mapping. Segregation ratios for seed infection and for SSR markers showed that a single dominant gene conditions resistance to PSS in PI 80837. The candidate resistance gene was mapped between Sat_308 (6.6 cM) and Satt594 (11.6 cM) on molecular linkage group G. These markers may be useful in marker-assisted selection for utilizing PSS resistance from PI 80837 in a breeding program.

  5. Uso de mezclas de azoxistrobina y triazoles para controlar enfermedades de fin de ciclo de la soja

    Directory of Open Access Journals (Sweden)

    Marcelo Carmona

    2011-06-01

    Full Text Available Las enfermedades de fin de ciclo de la soja (EFC, ampliamente difundidas en Argentina, afectan el rendimiento del cultivo y la calidad de la semilla cosechada. La aplicación foliar de fungicidas representa una alternativa eficiente en las actuales condiciones de cultivo (monocultivo y siembra directa. Los objetivos del presente trabajo fueron 1 determinar los agentes causales de la EFC presentes en los ensayos, 2 evaluar la disminución de rendimiento causada por las EFC y 3 valorar la eficiencia de control de mezclas de triazoles y azoxistrobina aplicados en las etapas reproductivas R3 o R5, para el control de las mismas. Se realizaron cuatro ensayos, dos en la campaña 2004/2005, y dos en la campaña 2005/2006, en Armstrong, Santa Fe, núcleo del área sojera de la Región Pampeana. Se utilizaron dos mezclas de azoxistrobina, una con cyproconazole y otra con difenoconazole, y una mezcla de los dos últimos. Los patógenos detectados fueron: Cercospora kikuchii, Colletotrichum truncatum, Septoria glycines, Glomerella glycines y Phomopsis sojae. Todos los tratamientos tuvieron mayores rendimientos que el control no tratado en todos los ensayos, con un nivel de significancia del 5%. Se concluye que, bajo las condiciones de los ensayos, con altas precipitaciones entre R1 y R5.5, los productos utilizados, controlaron eficientemente las EFC presentes.

  6. Bcmfs1, a novel major facilitator superfamily transporter from Botrytis cinerea, provides tolerance towards the natural toxic compounds camptothecin and cercosporin and towards fungicides.

    Science.gov (United States)

    Hayashi, Keisuke; Schoonbeek, Henk-Jan; De Waard, Maarten A

    2002-10-01

    Bcmfs1, a novel major facilitator superfamily gene from Botrytis cinerea, was cloned, and replacement and overexpression mutants were constructed to study its function. Replacement mutants showed increased sensitivity to the natural toxic compounds camptothecin and cercosporin, produced by the plant Camptotheca acuminata and the plant pathogenic fungus Cercospora kikuchii, respectively. Overexpression mutants displayed decreased sensitivity to these compounds and to structurally unrelated fungicides, such as sterol demethylation inhibitors (DMIs). A double-replacement mutant of Bcmfs1 and the ATP-binding cassette (ABC) transporter gene BcatrD was more sensitive to DMI fungicides than a single-replacement mutant of BcatrD, known to encode an important ABC transporter of DMIs. The sensitivity of the wild-type strain and mutants to DMI fungicides correlated with Bcmfs1 expression levels and with the initial accumulation of oxpoconazole by germlings of these isolates. The results indicate that Bcmfs1 is a major facilitator superfamily multidrug transporter involved in protection against natural toxins and fungicides and has a substrate specificity that overlaps with the ABC transporter BcatrD. Bcmfs1 may be involved in protection of B. cinerea against plant defense compounds during the pathogenic phase of growth on host plants and against fungitoxic antimicrobial metabolites during its saprophytic phase of growth.

  7. Effects of temperature during soybean seed development on defense-related gene expression and fungal pathogen accumulation.

    Science.gov (United States)

    Upchurch, Robert G; Ramirez, Martha E

    2011-12-01

    Soybean [Glycine max (L.) Merr] plants were exposed to three temperature regimens during seed development to investigate the effect of temperature on the expression of eight defense-related genes and the accumulation of two fungal pathogens in inoculated seeds. In seeds prior to inoculation, either a day/night warm (34/26 °C) or a cool temperature (22/18 °C) relative to normal (26/22 °C) resulted in altered patterns of gene expression including substantially lower expression of PR1, PR3 and PR10. After seed inoculation with Cercospora kikuchii, pathogen accumulation was lowest in seeds produced at 22/18 °C in which of all defense genes, MMP2 was uniquely most highly induced. For seeds inoculated with Diaporthe phaseolorum, pathogen accumulation was lowest in seeds produced at 34/26 °C in which of all defense genes, PR10 was uniquely most highly induced. Our detached seed assays clearly demonstrated that the temperature regimens we applied during seed development produced significant changes in seed defense-related gene expression both pre- and post inoculation and our findings support the hypothesis that global climate change may alter plant-pathogen interactions and thereby potentially crop productivity.

  8. Decomposition of corn and soybean residues under field conditions and their role as inoculum source

    Directory of Open Access Journals (Sweden)

    E.M. Reis

    2011-03-01

    Full Text Available Necrotrophic parasites of above-ground plant parts survive saprophytically, between growing seasons in host crop residues. In an experiment conducted under field conditions, the time required in months for corn and soybean residues to be completely decomposed was quantified. Residues were laid on the soil surface to simulate no-till farming. Crop debris of the two plant species collected on the harvesting day cut into pieces of 5.0cm-long and a 200g mass was added to nylon mesh bags. At monthly intervals, bags were taken to the laboratory for weighing. Corn residues were decomposed within 37.0 months and those of soybean, within 34.5 months. Hw main necrotrophic fungi diagnosed in the corn residues were Colletotrichum gramicola, Diplodia spp. and Gibberella zeae, and those in soybeans residues were Cercospora kikuchii, Colletotrichum spp, Glomerella sp. and Phomopsis spp. Thus, those periods shoulb be observed in crop rotation aimed at to eliminating contaminated residues and, consequently, the inoculum from the cultivated area.

  9. Evaluation of native and collected Germplasm for earliness Seed traits and resistance to rust, CMV and leaf spot in Cowpea [Vigna unguiculata (L. Walp].

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    K Sanjeev. Deshpand, B.R.Patil, P. M. Salimath , J.M. Nidagundi and S. Karthigeyan

    2010-07-01

    Full Text Available In the present study, 225 germplasm collections of cowpea including local types were evaluated in augmented design alongwith C152 (check for high test weight, desirable seed and pod features, earliness and resistance to Cowpea rust (Uromycesvignae, Cowpea Mosaic Virus (CMV and Cercospora leaf spot for two years ( kharif 2008 and kharif 2009 at Dharwad. Theresults of the investigation revealed that fifteen of the accessions showed bold seeds (test weight > 10g. Accession numberIC202932 and IC247435 showed extra bold seeds (test weight >14g and also bold pods. About 15 germplasm accessions werefound to be highly resistant to rust; 10 accessions displayed HR reaction to CMV and about 5 accessions showed highlyresistant reaction against leafspot. With respect to Multiple Disease Resistance, accession numbers IC201095, IC257406,IC257435 showed highly resistant reaction against leaf spot and CMV and accessions IC257410 and IC214753 showedresistance against rust and leaf spot. Some of the accessions identified against earliness are IC201087, IC201099,IC202707and IC202709 (68-75 days maturity. Such of the superior germplasm lines identified for earliness, multiple diseaseresistance, bold seed (100 seed weight > 12g and desirable seed features would be further useful in Cowpea breeding programas parents.

  10. Status of disease and insect in alfalfa and their controls in Linxia Regions, Gansu province%临夏地区紫花苜蓿病虫害发生现状调查及其防治对策

    Institute of Scientific and Technical Information of China (English)

    鲁鸿佩; 孙爱华

    2008-01-01

    经过3年多的田间调查和实验室鉴定,初步查清了临夏地区紫花苜蓿Medicago sativa病虫害发生的种类、分布、特点和危害程度.临夏地区苜蓿病害主要有褐斑病Pseudopeziza medicaginis、锈病Uromyecsstriatus、白粉病Leueillula leguminosarum、霜霉病Peronos pora estioalis、黄斑病Cercospora mesicaginis,炭疽病Colletotrichum trifolii、根腐病Rhizoctonia cyocorum 7种.苜蓿虫害主要有斜纹夜蛾、潜叶蝇、苜蓿蚜虫、蓟马4种.并在干旱半干旱、高寒阴湿和川塬灌区,根据不同地区苜蓿病虫害的发生及危害,开展了防治试验,提出了结合临夏地区生产实际防治苜蓿病虫害的对策.

  11. Influence of Cultural and Pest Management Practices on Performance of Runner, Spanish, and Virginia Market Types in North Carolina

    Directory of Open Access Journals (Sweden)

    Bridget R. Lassiter

    2016-01-01

    Full Text Available Virginia market type peanut (Arachis hypogaea L. cultivars are grown primarily in North Carolina, South Carolina, and Virginia in the US, although growers in these states often plant other market types if marketing opportunities are available. Information on yield potential and management strategies comparing these market types is limited in North Carolina. In separate experiments, research was conducted to determine response of runner, Spanish, and Virginia market types to calcium sulfate and inoculation with Bradyrhizobium at planting, planting and digging dates, planting patterns, and seeding rates. In other experiments, control of thrips (Frankliniella spp. using aldicarb, southern corn rootworm (Diabrotica undecimpunctata Howardi using chlorpyrifos, eclipta (Eclipta prostrata L. using threshold-based postemergence herbicides, and leaf spot disease (caused by the fungi Cercospora arachidicola and Cercosporidium personatum fungicide programs was compared in these market types. Results showed that management practice and market types interacted for peanut pod yield in only the planting date experiment. Yield of runner and Virginia market types was similar and exceeded yield of the Spanish market type in most experiments.

  12. Nuevo cultivar de soja de la EEAOC: Yanasu RR New soybean cultivar released by the EEAOC: Yanasu RR

    Directory of Open Access Journals (Sweden)

    José R. Sánchez

    2012-06-01

    Full Text Available Durante las últimas décadas, el cultivo de la soja a nivel mundial tuvo un crecimiento tanto en superficie, como en productividad. En la Argentina sucedió de igual manera, particularmente a comienzos de este siglo, como resultante del uso de alta tecnología, convirtiendo a este cultivo y a sus subproductos en el pilar del sistema granario y exportador. El desarrollo del Noroeste Argentino (NOA coincidió con el proceso a nivel nacional. La Estación Experimental Agroindustrial Obispo Colombres (EEAOC de Tucumán buscó permanentemente producir cultivares adaptados a esta zona, siendo este el principal objetivo del subprograma Mejoramiento Genético del Proyecto Soja. Yanasu es una nueva variedad de soja liberada por la EEAOC, que completa su madurez fisiológica a los 123 días de su siembra (pertenece al grupo de madurez VIII corto y que logra excelentes potenciales de rendimiento. Fue obtenida a través de cruzamiento y posterior avance generacional en la subestación de Monte Redondo (San Agustín, Tucumán. Yanasu RR fue sometida a ensayos comparativos de rendimiento (ECR en cuatro diferentes sitios del área sojera tucumana durante la campañas 2005/2006 y 2006/2007, alcanzando rendimientos superiores a los testigos en la mayoría de los ensayos. Exhibe, entre otras características, baja o nula dehiscencia de vainas y un peso de 1000 semillas de 162,6 gramos. En cuanto a su sanidad, se destaca su tolerancia a las enfermedades cancro del tallo y mancha ojo de rana, así como ante patógenos de semillas como Cercospora kikuchii, Alternaria spp. y Macrophomina spp. Desde 2009/2010 se la incluyó en la Red de Evaluación de Variedades Comerciales del NOA, destacándose por encima del testigo en 12 localidades de la región, con un excelente potencial de rendimiento.In recent decades, soybean planted area, production, and productivity have increased worldwide. This has also occurred in Argentina, especially during the last century, based on

  13. Potencial produtivo de linhagens de amendoim do grupo ereto precoce com e sem controle de doenças foliares Yield potential of upright early maturing peanut lines with and without control of foliar diseases

    Directory of Open Access Journals (Sweden)

    IGNÁCIO JOSÉ DE GODOY

    2001-01-01

    Full Text Available Avaliaram-se o potencial produtivo, o rendimento de grãos após descascamento e a massa de grãos de onze linhagens de amendoim (Arachis hypogaea L. do programa de melhoramento do Instituto Agronômico e da cultivar IAC-Tatu-ST, com e sem controle de doenças foliares. O material genético classifica-se no grupo ereto precoce (A. hypogaea subsp. fastigiata, Waldron. Seis experimentos foram desenvolvidos na época das águas, no Núcleo de Agronomia da Alta Mogiana e na Estação Experimental de Agronomia de Pindorama, em 1994/95, 1995/96 e 1996/97, em esquema com duas parcelas subdivididas, em blocos ao acaso com quatro repetições, em que as parcelas principais consistiram em tratamentos com e sem o controle químico das doenças. As parcelas tratadas foram pulverizadas periodicamente com 3,0 L.ha-1 do fungicida chlorothalonil para controle da mancha-castanha e da mancha-preta (Cercospora arachidicola e Cercosporidium personatum e da verrugose (Sphaceloma arachidis. A ausência de controle químico resultou em significativas reduções, até de 60%, na produção de todos os genótipos. Com as doenças controladas, as linhagens IAC 5, IAC 21, IAC 22 e IAC 81-12 apresentaram maior potencial produtivo, atingindo 5.000 kg.ha-1 em dois dos experimentos. As linhagens IAC 81-7 e IAC 88-1 apresentaram os melhores desempenhos relativos entre as médias de ambientes com e sem controle químico. As doenças causaram reduções até de 14% no peso médio dos grãos, sobretudo nas linhagens IAC 5, IAC 21 e IAC 22, cujos grãos são de maior tamanho médio. Não foram observadas diferenças significativas em rendimento de grãos entre os tratamentos, na maioria dos ambientes; essa característica mostrou, também, ser pouco influenciada pela presença das doenças.Eleven peanut lines and the cultivar IAC-Tatu-ST, of the upright early maturing group (Arachis hypogae subsp. fastigiata, Waldron, were evaluated for pod yield, shelling percentage and average

  14. Characterization of rust, early and late leaf spot resistance in wild and cultivated peanut germplasm Caracterização da resistência à ferrugem, mancha preta e mancha castanha em germoplasma silvestre e cultivado de amendoim

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    Alessandra Pereira Fávero

    2009-02-01

    Full Text Available Groundnut (Arachis hypogaea has an AB genome and is one of the most important oil crops in the world. The main constraints of crop management in Brazil are fungal diseases. Several species of the genus Arachis are resistant to pests and diseases. The objective of our experiments was to identify wild species belonging to the taxonomic section Arachis with either A or B (or " non-A" genomes that are resistant to early leaf spot (Cercospora arachidicola, late leaf spot (Cercosporidium personatum and rust (Puccinia arachidis. For the identification of genotypes resistant to fungal diseases, bioassays with detached leaves were done in laboratory conditions, with artificial inoculation, a controlled temperature of 25ºC and a photoperiod of 10 h light/14 h dark, for 20-42 days, depending on the fungi species. Most of the accessions of wild species were more resistant than accessions of A. hypogaea for one, two or all three fungi species studied. Arachis monticola, considered to be a possible tetraploid ancestor or a derivative of A. hypogaea, was also more susceptible to Cercosporidium personatum and Puccinia arachidis, as compared to most of the wild species. Therefore, wild germplasm accessions of both genome types are available to be used for the introgression of resistance genes against three fungal diseases of peanut.O amendoim (Arachis hypogaea possui genoma AB e é uma das mais importantes culturas oleaginosas em todo o mundo. Os principais problemas da cultura no Brasil são as doenças fúngicas. Várias espécies do gênero Arachis são resistentes a pragas e doenças. Este trabalho visou a identificar espécies silvestres pertencentes à seção Arachis associadas aos genomas A ou B (ou " não-A" do amendoim que são resistentes à mancha castanha (Cercospora arachidicola, mancha preta (Cercosporidium personatum e ferrugem (Puccinia arachidis. Para a identificação de genótipos resistentes a doenças fúngicas, bioensaios utilizando

  15. Greenhouse evaluation of Bacillus subtilis AP-01 and Trichoderma harzianum AP-001 in controlling tobacco diseases Avaliação em estufa de dois agentes biológicos de controle de doenças do tabaco

    Directory of Open Access Journals (Sweden)

    Monchan Maketon

    2008-06-01

    Full Text Available Two biological control agents, Bacillus subtilis AP-01 (LarminarTM and Trichoderma harzianum AP-001 (TrisanTM alone or/in combination were investigated in controlling three tobacco diseases, including bacterial wilt (Ralstonia solanacearum, damping-off (Pythium aphanidermatum, and frogeye leaf spot (Cercospora nicotiana. Tests were performed in greenhouse by soil sterilization prior to inoculation of the pathogens. Bacterial-wilt and damping off pathogens were drenched first and followed with the biological control agents and for comparison purposes, two chemical fungicides. But for frogeye leaf spot, which is an airborne fungus, a spraying procedure for every treatment including a chemical fungicide was applied instead of drenching. Results showed that neither B. subtilis AP-01 nor T. harzianum AP-001 alone could control the bacterial wilt, but when combined, their controlling capabilities were as effective as a chemical treatment. These results were also similar for damping-off disease when used in combination. In addition, the combined B. subtilis AP-01 and T. harzianum AP-001 resulted in a good frogeye leaf spot control, which was not significantly different from the chemical treatment.Dois agentes de controle biológico, Bacillus subtilis AP-01 (Larminar® e Trichoderma harzianum AP-001 (Trisan® foram avaliados separadamente ou em combinação quanto à capacidade de controlar três doenças do tabaco: murcha bacteriana (bacterial wilt, Ralstonia solanacearum, tombamento de mudas (damping-off, Pythium aphanidermatum, e mancha olho-de-rã (frogeye leaf spot, Cercospora nicotiana. Os testes foram realizados em estufa, esterilizando-se o solo antes da inoculação dos patógenos. Os patógenos causadores da murcha bacteriana e tombamento de mudas foram inicialmente encharcados e acompanhados com os agentes de controle biológico e, para comparação, com um fungicida químico. Para a mancha olho-de-rã, causada por um fungo anem

  16. Synthesis and Antifungal Activity of Camphoric Acid-based Thiourea Derivatives%樟脑酸基硫脲类化合物的合成及抑菌活性研究

    Institute of Scientific and Technical Information of China (English)

    马献力; 刘陆智; 段文贵; 石贤春; 李芳耀; 华忠泽

    2015-01-01

    Ten novel camphoric acid-based thiourea compounds (5a 5j) were prepared using camphoric acid and aminoethyl substituted phenyl thioureas as starting materials. The target compounds were characterized by FT-IR,1H NMR,13 C NMR,LC-MS,and elemental analysis. The antifungal activities of the compounds 5a 5j were tested. The preliminary bioassay showed that most of the target compounds exhibited certain antifungal activities,in which camphoric acid-based (o-methoxy)phenyl thiourea 5c (R=o-CH3O) and camphoric acid-based (m-methoxy)phenyl thiourea 5d (R=m-CH3O) had inhibition rate of 86. 9 % against Alternaria solani,and camphoric acid-based (m-methoxy)phenyl thiourea 5d,camphoric acid-based (m-methyl)phenyl thiourea 5g (R=m-CH3) and camphoric acid-based (p-bromo)phenyl thiourea 4i ( R=p-Br) had inhibition rate of 86. 1% against Physalospora piricola at the concentration of 50 mg/L. In addition,compound 5i also had the best inhibitory activity against cercospora arachidicola(73. 6%).%以樟脑酸和氨乙基取代苯基硫脲为原料,合成了10个新型的樟脑酸基硫脲类化合物(5a 5j). 利用FT-IR、1 H NMR、13 C NMR、LC-MS和元素分析等手段对目标产物进行了结构表征. 同时对化合物5a 5j的抑菌活性进行了测试. 初步的生物活性测试表明,在质量浓度为50 mg/L时,大部分化合物具有一定的抑菌活性,其中化合物樟脑酸基邻甲氧基苯基硫脲5c(R=o-CH3O)和樟脑酸基间甲氧基苯基硫脲5d(R=m-CH3O)对番茄早疫病菌(Alternaria solani)的抑制率达86. 9 %,化合物樟脑酸基间甲氧基苯基硫脲5d、樟脑酸基间甲基苯基硫脲5g( R=m-CH3 )和樟脑酸基对溴苯基硫脲5i(R=p-Br)对苹果轮纹病菌(Physalospora piricola)的抑制率达86. 1 %. 此外,化合物5i还对花生褐斑病毒(Cercospora arachidicola)具有最好的抑制率(73. 6%).

  17. 国内木薯病害普查及细菌性萎蔫病安全性评估%General Survey on Cassava Diseases and Safety Assessment of Cassava Bacterial Blight

    Institute of Scientific and Technical Information of China (English)

    李超萍; 时涛; 刘先宝; 蔡吉苗; 裴月令; 黄贵修

    2011-01-01

    2007~2010年,对广西、海南、云南等木薯主产区进行病害普查.结果发现,至今危害国内木薯的主要病害有7种,包括真菌病害6种[褐斑病(Cercosporidium henningsii)、炭疽病(colletotrichum gloeosPorioides)、离孺孢叶斑病(Bipolaris setariae)、棒孢霉叶斑病(Corynespora cassiicola)、白点病(phaeoramularia manihotis)和萎蔫叶斑病(Cercospora vicosae)],细菌病害1种[细菌性萎蔫病(Xanthomonas axonopodis pv manihotis)],其中离孺孢叶斑病和棒孢霉叶斑病为新发病害;7种病害中褐斑病和细菌性萎蔫病发生面积最大,危害最为严重.风险评估结果表明,细菌性萎蔫病菌为高度危险性有害生物.%During 2007 to 2010, cassava(Manihot esculenta Crantz)diseases survey was conducted in Guangxi, Hainan and Yunnan, the main cassava planting areas of China. The results showed that only seven diseases, six fungal diseases and one bacterial disease, were found. The cassava brown leaf spot caused by Cercosporidium henningsii and the bacterial blight caused by Xanthomonas axonopodis pv Manihotis prevailed in most cassava planting areas and caused serious damage. The safety assessment indicated that the cassava bacterial blight was a high risk disease. At present, cassava diseases are becoming one of the most important limiting factors for the development of cassava industry and would have a very serious,potential economic risk on correlative industry and the ecology of the tropic area.

  18. Predicting favorable conditions for early leaf spot of peanut using output from the Weather Research and Forecasting (WRF) model.

    Science.gov (United States)

    Olatinwo, Rabiu O; Prabha, Thara V; Paz, Joel O; Hoogenboom, Gerrit

    2012-03-01

    Early leaf spot of peanut (Arachis hypogaea L.), a disease caused by Cercospora arachidicola S. Hori, is responsible for an annual crop loss of several million dollars in the southeastern United States alone. The development of early leaf spot on peanut and subsequent spread of the spores of C. arachidicola relies on favorable weather conditions. Accurate spatio-temporal weather information is crucial for monitoring the progression of favorable conditions and determining the potential threat of the disease. Therefore, the development of a prediction model for mitigating the risk of early leaf spot in peanut production is important. The specific objective of this study was to demonstrate the application of the high-resolution Weather Research and Forecasting (WRF) model for management of early leaf spot in peanut. We coupled high-resolution weather output of the WRF, i.e. relative humidity and temperature, with the Oklahoma peanut leaf spot advisory model in predicting favorable conditions for early leaf spot infection over Georgia in 2007. Results showed a more favorable infection condition in the southeastern coastline of Georgia where the infection threshold were met sooner compared to the southwestern and central part of Georgia where the disease risk was lower. A newly introduced infection threat index indicates that the leaf spot threat threshold was met sooner at Alma, GA, compared to Tifton and Cordele, GA. The short-term prediction of weather parameters and their use in the management of peanut diseases is a viable and promising technique, which could help growers make accurate management decisions, and lower disease impact through optimum timing of fungicide applications.

  19. Analysis of Gene Expression Profiles in Leaf Tissues of Cultivated Peanuts and Development of EST-SSR Markers and Gene Discovery.

    Science.gov (United States)

    Guo, Baozhu; Chen, Xiaoping; Hong, Yanbin; Liang, Xuanqiang; Dang, Phat; Brenneman, Tim; Holbrook, Corley; Culbreath, Albert

    2009-01-01

    Peanut is vulnerable to a range of foliar diseases such as spotted wilt caused by Tomato spotted wilt virus (TSWV), early (Cercospora arachidicola) and late (Cercosporidium personatum) leaf spots, southern stem rot (Sclerotium rolfsii), and sclerotinia blight (Sclerotinia minor). In this study, we report the generation of 17,376 peanut expressed sequence tags (ESTs) from leaf tissues of a peanut cultivar (Tifrunner, resistant to TSWV and leaf spots) and a breeding line (GT-C20, susceptible to TSWV and leaf spots). After trimming vector and discarding low quality sequences, a total of 14,432 high-quality ESTs were selected for further analysis and deposition to GenBank. Sequence clustering resulted in 6,888 unique ESTs composed of 1,703 tentative consensus (TCs) sequences and 5185 singletons. A large number of ESTs (5717) representing genes of unknown functions were also identified. Among the unique sequences, there were 856 EST-SSRs identified. A total of 290 new EST-based SSR markers were developed and examined for amplification and polymorphism in cultivated peanut and wild species. Resequencing information of selected amplified alleles revealed that allelic diversity could be attributed mainly to differences in repeat type and length in the SSR regions. In addition, a few additional INDEL mutations and substitutions were observed in the regions flanking the microsatellite regions. In addition, some defense-related transcripts were also identified, such as putative oxalate oxidase (EU024476) and NBS-LRR domains. EST data in this study have provided a new source of information for gene discovery and development of SSR markers in cultivated peanut. A total of 16931 ESTs have been deposited to the NCBI GenBank database with accession numbers ES751523 to ES768453. PMID:19584933

  20. Purification and characterisation of an antifungal protein, MCha-Pr, from the intercellular fluid of bitter gourd (Momordica charantia) leaves.

    Science.gov (United States)

    Zhang, Beibei; Xie, Chengjian; Wei, Yunming; Li, Jing; Yang, Xingyong

    2015-03-01

    An antifungal protein, designated MCha-Pr, was isolated from the intercellular fluid of bitter gourd (Momordica charantia) leaves during a screen for potent antimicrobial proteins from plants. The isolation procedure involved a combination of extraction, ammonium sulphate precipitation, gel filtration on Bio-Gel P-6, ion exchange chromatography on CM-Sephadex, an additional gel filtration on HiLoad 16/60 Superdex 30, and finally, HPLC on a SOURCE 5RPC column. Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry indicated that the protein had a molecular mass of 25733.46Da. Automated Edman degradation was used to determine the N-terminal sequence of MCha-Pr, and the amino acid sequence was identified as V-E-Y-T-I-T-G-N-A-G-N-T-P-G-G. The MCha-Pr protein has some similarity to the pathogenesis-related proteins from Atropa belladonna (deadly nightshade), Solanum tuberosum (potato), Ricinus communis (castor bean), and Nicotiana tabacum (tobacco). Analysis of the circular dichroism spectra indicated that MCha-Pr predominantly contains α-helix and β-sheet structures. MCha-Pr had inhibitory effects towards a variety of fungal species and the 50% inhibition of fungal growth (IC50) for Alternaria brassicae, Cercospora personata, Fusarium oxysporum, Mucor sp., and Rhizoctonia solani are 33 μM, 42 μM, 37 μM, 40 μM, and 48 μM, respectively. In addition, this antifungal protein can inhibit the germination of A. brassicae spores at 12.5 μM. These results suggest that MCha-Pr in bitter gourd leaves plays a protective role against phytopathogens and has a wide antimicrobial spectrum. PMID:25245535

  1. Influence of He-Ne laser irradiation of soybean seeds on seed mycoflora, growth, nodulation, and resistance to Fusarium solani.

    Science.gov (United States)

    Ouf, S A; abdel-Hady, N F

    1999-01-01

    Laser irradiation of soybean seeds for 3 min caused a clear reduction in the number of seed-borne fungi which became more pronounced as the irradiation time was extended. Pretreatment of the seeds with methylene blue, methyl red and carmine enhanced the effect of laser. Rhizoctonia solani, Alternaria tenuissima, Cercospora kikuchii and Colletotrichum truncatum were completely eliminated when the seeds were pretreated with a dye and irradiated for 10 min. Seed germination was stimulated on exposure of the seed to 1-min irradiation. At such dose, most of the dyes were accelerators while the higher doses were inhibitory to seed germination. Chlorophyll a, chlorophyll b and carotenoid content of developed plants differed, depending on the irradiation dose and dye treatment of the seeds. In seeds irradiated for 1 or 3 min, chlorophyll a formation was less affected than chlorophyll b formation. In seeds irradiated for 10 min, both the chlorophyll contents were decreased especially in the presence of some applied dyes. On the other hand, there was an increase in carotenoid content of soybean leaves when the laser dose increased. The number and dry mass of nodules were mostly greater (as compared to the corresponding control), when the seeds irradiated for 1 or 3 min were pretreated with methyl red, chlorophenol red, crystal violet and methylene blue. Irradiation of pre-sowing seeds greatly protected soybean stands against F. solani. The disease incidence differed somewhat when the irradiated seeds were pretreated with dyes. The reduction in disease incidence was accompanied by accumulation of high proline and phenol levels in the infected root tissues of soybean, suggesting that these compounds have a certain role in the prevention of disease development.

  2. Características agronómicas y sanidad de germoplasma promisorio de maní (Arachis hypogaea L. en Quevedo, Ecuador

    Directory of Open Access Journals (Sweden)

    Felipe Rafael Garcés-Fiallos

    2014-12-01

    Full Text Available Durante las épocas secas de 2010 y 2011, en la finca experimental La María de la Universidad Técnica Estatal de Quevedo, Ecuador, localizada en el km. 7.5 vía Quevedo-El Empalme, a 79° 30' 08" O y 01° 00' 35" S, se evaluaron las características agronómicas y las condiciones sanitarias de líneas y variedades de maní (Arachis hypogaea L.. Se utilizaron las líneas promisorias de maní CB-02, CB-05, CB-12, CB-13, CB-15, CB-16 y CB-23 de la Universidad y como testigos las variedades comerciales Diamante, Polachi, INIAP-380 e INIAP-381. Se midieron la emergencia de plántulas, días a floración, altura de planta, algunos componentes productivos (número de granos, frutos llenos y estériles, peso de frutos y granos y la presencia de cercosporiosis (Cercospora arachidicola y Cercosporidium personatum y roya (Puccinia arachidis. Se utilizó un diseño de bloques completos al azar (DBCA con 11 tratamientos y tres repeticiones en 2010 y cuatro repeticiones en 2011. Para las comparaciones entre las medias de los tratamientos se empleó la prueba de rangos múltiples de Duncan (P < 0.05. La línea CB-23 se destacó entre el germoplasma promisorio por su mayor productividad; esta misma línea junto con la variedad comercial INIAP-380, presentaron los menores ataques de cercosporiosis. La línea CB-15 y la variedad Polachi no presentaron lesiones de la roya.

  3. Increased levels of ambient fungal spores in Taiwan are associated with dust events from China

    Science.gov (United States)

    Wu, Pei-Chih; Tsai, Jui-Chen; Li, Fang-Chun; Lung, Shih-Chun; Su, Huey-Jen

    2004-09-01

    Fungi are ubiquitous in nature and their spores are often dispersed into the atmosphere through turbulent airstreams. As yellow sandstorm blown from deserts in China had affected the ambient air quality with increasing levels of ambient particulates, often including significant amounts of biologically active particles has therefore become imperative for concerns of their health implications. Our study was aimed to examine the effects of yellow sandstorm events on the fungal composition and concentrations in ambient air. Atmospheric fungal spores were continuously collected using Burkard Volumetric Spore Trap. Samples collected between December 2000 and April 2001 were selected for priority analysis from days when the yellow sandstorms were reported to affect Taiwan according to the Central Weather Bureau in Taiwan. The composition of dominant spores such as Basidiospore, Penicillium/Aspergillus, Nigrospora, Arthrinium, Curvularia, Rusts, Stemphylium, Cercospora, Pithomyces, and unidentified fungi were significantly higher than those of background days. The increase of Basidiospore, Penicillium/Aspergillus, Nigrospora, and those unidentified fungi seems to be significantly associated with the increase of ambient particulate levels with regression coefficients ranging from 0.887 to 31.98. Our study has identified increasing ambient concentrations during sandstorm episodes are observed for some major fungi, Basidiospore, Penicillium, Aspergillus, and those unidentified fungi and the trends of the increase seems to associate with ambient particulate levels. Further efforts to clarify the relationship between those high fungal spore exposures and clinical adverse health effects are suggested in the future. In addition, effects of climatic factors and other particulate levels on the variation of ambient fungal spore levels are also desired in further study. Additional monitoring of ambient fungal spores in the first line of west coastline is hoped to assist in

  4. The phytosanitary form and fighting measures diseases and pests of sugar beet from Republic of Moldova

    Directory of Open Access Journals (Sweden)

    Timus Asea M.

    2006-01-01

    Full Text Available Sugar beet is one of the most important agricultural crops in the Republic of Moldova. The North and Central regions have good enough pedoclimatic conditions. The genetic potential of sorts and hybrids can be created through the application of modern technologies in order to grow at least 32-35 tons/ha of sugar beet roots. In the Republic of Moldova, sugar beet vegetates between 160 and 180 days in the first year and needs approximately an amount of 2400-2900°C, average of 15.3-15.4°C. Each phenological phase needs different temperatures: at least 4C° is necessary for planting and springing an amount of 650°C is necessary for foliar apparatus; an amount of 1150- 1800°C is necessary to grow the volume of roots and for sugar depositing the average of 2400 to 2600°C is necessary. The mentioned temperatures ensure a normal development of sugar beet plants. If these temperatures fluctuate, the pathogens and pests are stimulated to develop. The most frequent diseases of sugar beet are: Pythium de baryanum Hesse., Aphanomyces cochlioides Dresch. Peronospora schachtii Fuck., Phoma betae Fr. Cercospora beticola Sacc. Erysiphe communis Grev. f. betae Jacz., virosis - Beta virus 2, 3 si 4 etc. The main pests belong to the following categories: Homoptera: Aphis fabae Scop. (fam. Aphididae, Pemphigus fuscicornis Koch. (fam. Pemphigidae Coleoptera: Agriotes sp. (fam. Elateridae, Chaetocnema concinna M. Ch. breviuscula Fld., Cassida nebulosa L. (fam. Chrysomelidae, Atomaria linearis Step. (fam. Cryptophagidae; Bothynoderes punctiventris Germ., Tanymechus dilaticollis Gyll., T. palliatus F., Psalidium maxillosum F. (Curculionidae; Lepidoptera: Agrotis segetum Den. et Schiff., Authographa gamma L. Mamestra (Barathra brassicae L. (Noctuidae, Loxostege sticticalis L. (Pyralidae, Gnorimoschema ocellatella Boyd.; Diptera Pegomyia betae Curtis. (fam. Anthomyidae. Heterodera schachtii Schmidt (Heteroderidae. The most recommended insecticides for fighting the

  5. Effects of ultraviolet radiation on Hibiscus rosa-sinensis, Beta vulgaris and Helianthus annuus

    Energy Technology Data Exchange (ETDEWEB)

    Panagopoulos, I.

    1992-01-01

    It is believed that increased levels of ultraviolet B-radiation (UV-B;280-320 nm) will result in serious threat to plant. In the present study the effects of UV (particularly UV-B) were studied on chlorophyll fluorescence, ultraweak luminescence (UL) and plant growth. Parameters related to light emission were determined, and the effects of UV-B on hypocotyl elongation and levels of free IAA were examined. The plants were grown in greenhouse or in growth chambers and exposed to short or long term UV-B simulating different levels of ozone depletion. Short exposure of Hibiscus leaves to UV resulted in a gradual increase in both UL and peroxidase activity followed by a decline after 72 h and a decrease in variable chlorophyll fluorescence. The action of UV-B on sugar beet plants depended on light quality and irradiance and infection by Cercospora beticola Sacc. The interaction between UV-B and the disease resulted in a large reduction of dry weight and enhanced UL. The lowest Chl a and growth was found in plants grown under low irradiance and exposed to UV-B supplemented with UV-A (320-400 nm). UVB also inhibited photosystem II, increased UL and peroxidase activity. Under relatively high PAR, UV-B increased dry weight of laminae and UL but no effect on Chl content. Sugar beet plants grown with light depleted in the 320-400 nm region of the spectrum and exposed to UV-B died. Low levels of UV-B did neither affected hypocotyl elongation nor amounts of free IAA in sunflower plants grown under low (LL; 143 [mu]mol m[sup -2]s[sup -1]) or high PAR (HL; 800 [mu]mol m[sup -2]s[sup -1]). Three times more daily UV-B increased the amount of free IAA, but inhibited hypocotyl elongation. Higher F[sub v]/F[sub max] and F690/F735, Chl a and carotenoids were found in plants exposed to low UV-B. Indeed, UV-B can be harmful but may also have enhancing effects on plants. (au) (114 refs.).

  6. Effects of ultraviolet radiation on Hibiscus rosa-sinensis, Beta vulgaris and Helianthus annuus

    International Nuclear Information System (INIS)

    It is believed that increased levels of ultraviolet B-radiation (UV-B;280-320 nm) will result in serious threat to plant. In the present study the effects of UV (particularly UV-B) were studied on chlorophyll fluorescence, ultraweak luminescence (UL) and plant growth. Parameters related to light emission were determined, and the effects of UV-B on hypocotyl elongation and levels of free IAA were examined. The plants were grown in greenhouse or in growth chambers and exposed to short or long term UV-B simulating different levels of ozone depletion. Short exposure of Hibiscus leaves to UV resulted in a gradual increase in both UL and peroxidase activity followed by a decline after 72 h and a decrease in variable chlorophyll fluorescence. The action of UV-B on sugar beet plants depended on light quality and irradiance and infection by Cercospora beticola Sacc. The interaction between UV-B and the disease resulted in a large reduction of dry weight and enhanced UL. The lowest Chl a and growth was found in plants grown under low irradiance and exposed to UV-B supplemented with UV-A (320-400 nm). UVB also inhibited photosystem II, increased UL and peroxidase activity. Under relatively high PAR, UV-B increased dry weight of laminae and UL but no effect on Chl content. Sugar beet plants grown with light depleted in the 320-400 nm region of the spectrum and exposed to UV-B died. Low levels of UV-B did neither affected hypocotyl elongation nor amounts of free IAA in sunflower plants grown under low (LL; 143 μmol m-2s-1) or high PAR (HL; 800 μmol m-2s-1). Three times more daily UV-B increased the amount of free IAA, but inhibited hypocotyl elongation. Higher Fv/Fmax and F690/F735, Chl a and carotenoids were found in plants exposed to low UV-B. Indeed, UV-B can be harmful but may also have enhancing effects on plants. (au) (114 refs.)

  7. Inhibitory activity of Cymbopogon citratus essential oil against nine phytopathogens%柠檬草精油对9种植物病原菌的抑菌活性

    Institute of Scientific and Technical Information of China (English)

    赵杰; 周超英; 顾振芳; 姚雷

    2011-01-01

    By the mycelium growth rate methods, the inhibitory activities of Cymbopogon citratus essential oil was tested against Valsa ambiens (Pers. ) Fr, Diaporthe citri (Fazvcett) Wolf, Alternaria citri, Colletotrichum orbicalare, Fusarium oxysporum f. Sp. Melonis, Alternaria alternate, Didymella bryoniae, and Cercospora fabae . The results showed that C. Citratus essential oil had good inhibition effects on 8 fungi and EC50 were 308. 052 2,433. 319 6,399. 733 8,319. 010 3,366. 895 7,279. 126 1,270. 738 8 and 333. 495 6 fiL/L respectively. In additions, inhibition zone experiment showed that C. Citratus essential oil had good inhibition effect on Xanthomonas pruni (Smith) Down with 500 μL/L of minimum inhibitory concentration MIC).%采用生长速率法测定了柠檬草精油对梨树腐烂病菌、柑橘树脂病菌、柑橘黑腐病菌、西瓜炭疽病菌、甜瓜枯萎病菌、甜瓜叶斑病菌、甜瓜蔓枯病菌、蚕豆轮纹病菌的抑菌活性.结果表明,柠檬草精油对8种病原真菌都具有很好的抑菌活性,其EC50分别为308.052 2、433.319 6、399.733 8、319.010 3、366.895 7、279.126 1、270.738 8和333.495 6μL/L;用抑菌圈法测定了柠檬草精油对桃细菌性穿孔病菌的抑菌活性,结果表明,柠檬草精油对桃细菌性穿孔病菌也具有一定的抑菌活性,其最低抑菌浓度为500 μL/L.

  8. Influência da adubação nitrogenada, época de plantio e aerosporos sobre a severidade da mancha de grãos em arroz de terras altas

    Directory of Open Access Journals (Sweden)

    Valácia Lemes da Silva-Lobo

    2011-09-01

    Full Text Available A mancha de grãos (MG ocupa o segundo lugar em importância econômica entre as doenças do arroz. Foi estudada a influência de níveis de adubação nitrogenada, época de plantio e concentração de esporos no ar sobre a severidade da doença no campo. A severidade de MG, na cultivar BRS Bonança, foi avaliada em duas épocas de plantio (30/11/2006 e 21/12/2006 e cinco doses de adubação nitrogenada (0, 30, 60, 120 e 240 kg de N.ha-1 utilizando o delineamento experimental de blocos ao acaso em esquema de parcelas subdivididas com três repetições. O efeito de dose de N sobre a severidade de MG não foi significativo. A correlação entre a severidade de MG e espiguetas vazias foi positiva e significativa. A população de fungos no ar (aerosporos foi quantificada utilizando armadilhas volumétricas, Rotorod Sampler, desde a emissão até o amadurecimento das panículas. A mancha de grãos aumentou linearmente com tempo (r = 0,98; P < 0,01, o mesmo não ocorreu com o aumento total de fungos que variou de 0,23 a 2,97 esporos/litro de ar/minuto. Os fungos presentes no ar em ordem decrescente de concentração foram Nigrospora sp., Pyricularia oryzae, Pithomyces sp., Alternaria sp., Cercospora sp., Fusarium sp., Curvularia sp. e Bipolaris sp. Estes fungos e Phoma sp. entre outros também foram detectados no teste de sanidade de sementes. A correlação entre a quantidade de esporos de P. oryzae e outros fungos foi linear e positiva (r = 0,80, P < 0,01. O número de esporos aumentou com o aumento da umidade relativa e diminuiu com o aumento da temperatura máxima de maneira exponencial.

  9. Antifungal Activity of The Extraction of Hopea chinensis Stem and Leaves Against Plant Pathogenic Fungi%狭叶坡垒枝叶粗提物抑菌活性研究

    Institute of Scientific and Technical Information of China (English)

    熊婷; 许亚楠; 周明晓晗; 苏坚; 王忠文; 唐文伟

    2016-01-01

    With the growth rate method,15 kinds of plant materies were selected for their antifungal activity against Fusarium oxysporum Schl. f. sp. cucumerirum Owen,Alternaria longipes( Ell. et Eu) Tisdale et Wadk,Curvularia lunata (Wakker) Boedijin,Botrytis cinerea Pers,and Rhizoctonia solani Kuhn.The results were as follows.Hopea chinensis Hand.Mass,Solanum touvum swartz together and other five materials showed inhibitory activity,H. chinensis showed the strongest inhibition.Further experiment on the antifungal activity of the petro⁃leum,ethyl acetate and water extracts of H. chinensisi stem and leaves with against 21 plant pathogenic fungi such as Helminthosporium turcicum Pass,Helminthosporium oryzae Breda de Haan,Fusarium oxysporum Schl. f. sp and other 21 plant was determined.The results showed that the ethyl acetate extract of H. chinensis had high antifungal activity against 18 plant pathogenic fungi such as Gibberella fujikuroi ( Saw) Wollenw, Mycosphaere⁃lla fijiensis Mareletto,Cercospora musae Zimm. Their antifungal activity against Phytophthora nicotianae Breda was the strongest whose inhibiting rate was 100%,flowed by that against Alternaria musae Bour. et Bat,Curv⁃alaria lunata(Wakker) Boedijin,Ceratocystis paradoxa(Dade)Moreau,Alternaria brassicola(Schw.)Wiltshire, Rhizoctonia solani Kuhn,whose inhibiting rates were 89.00%,94.12%,90.35%,89.93% and 95.13%,respective⁃ly,and whose EC50 were 0.475 8mg/mL,2.642 9 mg/mL,0.614 7 mg/mL,0.467 4 mg/mL,0.977 7 mg/mL and 3.463 7 mg/mL,respectively.The spore germination experiment was conducted on C. paradoxa and A.brassicola using ethyl acetate extract of H. chinensis and the EC50 of each were 0. 716 6 mg/mL and 1. 784 4 mg/mL, respectively.The results lay the foundation for further investigation on the active antifungal components in Hopea chinensis.%采用菌丝生长速率法,以西瓜枯萎菌( Fusarium oxysporum Schl. f. sp. cucumerirum Owen)、烟草赤星菌[ Al⁃ternaria longipes(Ell. et

  10. Efeito da aplicação de fungicida sobre caracteres agronômicos e severidade das doenças de final de ciclo na cultura da soja. = Effect of fungicide application on Agronomic characteristics and final cycle diseases severity in soybean.

    Directory of Open Access Journals (Sweden)

    Everton Luis Finoto

    2011-04-01

    Full Text Available Nas últimas safras, um complexo de doenças, chamadas de doenças de final de ciclo da soja (DFC, vem provocando reduções consideráveis no rendimento da cultura. Atualmente, não há variedades resistentes a todos os patógenos causadores das DFC. Objetivou-se no presente trabalho avaliar o efeito da aplicação de fungicida em diferentes estádios reprodutivos, nos caracteres agronômicos e severidade das DFC em três cultivares de soja de diferentes grupos de maturação. O trabalho foi conduzido em área experimental da Universidade Federal de Viçosa. Foram realizados quatro tratamentos com fungicida sendotrês aplicações em estádios reprodutivos diferentes (R5, R5,5 e R6 e a testemunha sem aplicação. As cultivares utilizadas foram: BRSMG Liderança, UFVS 2001 e UFVS 2003. Foi avaliado: altura da planta, altura da inserção da primeira vagem, número de nós por planta, número de vagens por planta, peso total da planta e peso de sementes. A severidade das DFC foi avaliada no estado R6 através de escala de notas. Os dados das avaliações foram submetidos aos testes de normalidade e homogeneidade constatando-se a desnecessidade de transformações. Realizou-se as análises de variância e as médias foram comparadas pelo teste de Tukey, a 5% de probabilidade de erro. Na avaliação da severidade das doenças, foi constatada a presença dos seguintes patógenos: Septoria glycines, Cercospora kikuchii e Peronospora manshurica. Para a avaliação das características agronômicas foi observado que a cultivar UFVS 2001 apresentou maiores alturas de planta. A cultivar UFVS 2003 apresentou maior númerode nós e também maior produtividade de grãos, seguida pela cultivar Liderança. A aplicação de fungicida proporcionou o controle satisfatório de Septoria glycines no folíolo, quando realizada no estádio R5. A aplicação do fungicida proporcionou também aumento na produtividade de grãos, sendo os melhores resultados obtidos

  11. Doenças da mandioquinha-salsa e sua situação atual no Brasil Present situation of arracacha (Arracacia xanthorrhiza diseases in Brazil

    Directory of Open Access Journals (Sweden)

    Gilmar P. Henz

    2002-06-01

    Full Text Available Este artigo tem como objetivo principal relatar as doenças registradas para a mandioquinha-salsa até a data presente e descrever sua situação atual no País. Na literatura, foram registrados para a cultura 27 gêneros de fungos, três de bactérias, doze de nematóides e cinco espécies de vírus. Destes, já foram relatados no Brasil treze fungos, e todos nematóides e bactérias, enquanto nenhum vírus foi oficialmente registrado, embora já tenham sido observadas plantas com sintomas típicos de viroses a campo. A maior parte dos registros estão na forma de resumos, capítulos de livros ou publicações genéricas, desprovidos de uma série de dados relevantes, como provas de patogenicidade, importância da doença, perdas, identificação mais acurada, entre outras. A cultura da mandioquinha-salsa ainda é tida como rústica, sendo poucas as doenças consideradas limitantes. O nematóide das galhas (Meloidogyne spp. e a podridão-mole pós-colheita causada por Erwinia spp. são os principais problemas atualmente, e causam perdas significativas. Também ocorrem com muita frequência manchas foliares causadas por Septoria, Cercospora e Xanthomonas campestris pv. arracaciae, e em algumas regiões podridão de plantas a campo causadas por Sclerotinia sclerotiorum e Sclerotium rolfsii. Como não existe nenhum produto químico oficialmente registrado para a mandioquinha-salsa no Ministério da Agricultura, Pecuária e Abastecimento, as medidas de controle passíveis de recomendação incluem ações preventivas, como o uso de material propagativo sadio (preferencialmente mudas pré-enraizadas de origem conhecida, a adoção de rotação de culturas, a eliminação de plantas ou partes doentes, e a adubação e a irrigação adequadas. O estudo sistematizado das doenças e o registro cuidadoso de surtos ou novas enfermidades para a cultura são importantes para subsidiar futuras medidas de controle.The diseases of arracacha that have already

  12. Fungal pathogens intercepted in imported germplasm of medicinal and aromatic plants and their quarantine significance

    Directory of Open Access Journals (Sweden)

    Usha Dev

    2011-01-01

    -borne pathogen and potential mycoherbicide for opium poppy crop. Alternaria zinniae Pape ex. Ellis and Botrytis alli Munn having limited geographical distribution in the country; Fusarium oxysporum Schlecht., known to possess a number of physiological races; B. cinerea Pers. Fr., Botryodiplodia theobromae Pat., Colletotrichum dematium (Pers. Grove, C. gloeosporioides (Penz. Sacc., Drechslera sorokiniana (Sacc. Subram. & Jain, F moniliforme Sheldon, F solani (Mart. Sacc., Macrophomina phaseolina (Tassi Goid and Rhizoctonia solani Kuhn etc. having wide host range. Further Alternaria brassicicola (Schw. Wiltshire and F solani (Mart. Sacco on non-host crops and Ascochyta sp., A. linicola, A. ricini Groves & Skolko, Curvularia lunata (Wakker Boedjin, Cercospora traversciana Sacc., D. papaveris, Pestalotia sp. and Phomopsis phaseoli Sacco causing damage of economic significance also were intercepted. Introduction of these exotic pathogens or their more virulent strains along with germplasm could pose a serious threat to the indigenous crops. Interception of such a large number of pathogens signifies the role of quarantine in regulating the safe introduction of plant genetic resources needed for the crop improvement programmes of medicinal and aromatic plants of the country.

  13. 惠州西湖景区古树名木病虫害调查及保护建议%Investigations on the diseases and insect pests of the ancient and famous trees of West Lake scenic area in Huizhou and suggestions for their protection

    Institute of Scientific and Technical Information of China (English)

    钟平生; 汤玉娟; 张颂声

    2011-01-01

    [目的]了解广东惠州西湖景区古树名木病虫害发生情况,为西湖景区古树名木养护管理提供参考.[方法]采用普查和抽查相结合的方法,并参考相关文献,对惠州西湖景区内古树名木主要病虫害种类及危害程度进行调查和鉴定.[结果]西湖景区内古树名木共有8科8属9种31棵,病害共12种,其中危害叶片的病害主要有灰斑病、炭疽病、褐斑病、藻斑病、煤污病等,危害树干的病害主要有枝枯病、干腐病;虫害有6目14科19种,其中刺吸性害虫和食叶性害虫主要有榕管蓟马、绵蚧、荔蝽、榕卵痣木虱、天蛾、中国绿刺蛾、棉大卷叶蛾和丽绿刺蛾等,蛀干害虫主要有家白蚁、眉斑楔天牛和云斑天牛等.叶部病害、刺吸性害虫和食叶性害虫对植株的危害较轻,枝枯病、干腐病和家白蚁等对植株的危害较严重.[建议]加强宣传,提高人们对古树名木的保护意识;加强对古树名木的复壮修补及病虫害防治工作;采用科学技术,防控园林植物病虫害.%[Objective]The objective of the current study was to investigate the occurrence of diseases and insect pests of the ancient and famous trees in West Lake scenic area in Huizhou, and to provide reference for their scientific conservation and management. [Method]The main diseases and insect pests in the old trees and the grade of damages caused by them were investigated using methods of general investigation and random inspection and referring to the relevant literatures.[Result]Thirty--one old trees corresponding to 9 species, 8 genus, 8 families were found in West Lake scenic area. Twelve kinds of diseases, identified in these trees, which damaged leaves of old trees were Cercospora Sojina Hara, anthracnose,brown patch, Cephaleuros spp, sooty blotch, while the diseases which damaged stem were branch rot and dry rot. Nineteen species of insects corresponding to 14 families of 6 orders were found in scenic area, of

  14. Study on Effect of Several Herbicides on Weeds and Diseases of Mung Bean (Vigna radiata)in Field%几种除草剂对绿豆田杂草的防治效果及绿豆病害影响的研究

    Institute of Scientific and Technical Information of China (English)

    葛维德; 付思齐; 薛仁风; 赵阳; 栾好民

    2014-01-01

    Mung bean (Vigna radiata)is an important grain,vegetables and medicinal crops,nutritional and medicinal value are both high.It plays an important role in the adjustment of planting structure and optimiza-tion of planting pattern.In this study,10 herbicide combinations were applied for controlling weeds in the mung bean field,the effect was compared among 10 different combinations in order to discover the suitable weed-controlling method for Liaoning province.The results showed that No.4 combination (fomesafen and high -flurbiprofen diclofop),No.5 combination (sethoxydim and fomesafen)and No.10 combination (quiza-lofop and fomesafen)had the best controlling effect,percentage of controlling effects were 92.3%,95.5%and 93.5%,respectively.Among these,No.10 combination showed highest hectare yield of 1326.9 kg.In addition,No.1 combination (metolachlor and fomesafen),No.5 combination (sethoxydim and fomesafen) and No.1 1 combination (quizalofop and fluoroglycofen)also played a role in controlling diseases in mung bean field.No.1 1 combination showed best effect,and the disease scores of Cercospora leaf spot and bacterial blight of mung bean were only 3.2 and 4.2,respectively.In this study,we analyzed the effects of 10 different herbicide combinations on the weed-controlling,yield per hectare and disease controlling in the field of mung bean in order to provide technical guidline for weed-controlling in Liaoning province.%绿豆(Vigna radiata)是重要的粮食、蔬菜和药用作物,营养价值和药用价值均很高,在农业种植结构调整和种植模式的优化中具有重要的作用。研究通过10种除草剂组合防除绿豆田杂草,比较不同组合间杂草防除效果的差异,筛选出适用于辽宁地区的杂草防除方法。结果表明,除草效果最好的是4号组合(氟磺胺草醚高效氟吡甲禾草灵苗后喷雾),5号组合(拿捕净氟磺胺草醚苗后喷雾)和10号组合(精喹禾灵、氟磺胺草醚苗

  15. Preliminary Identification of Six Antagonistic Actinomycetes in Soil Determination of Its Fungicidal Activities%6株土壤拮抗放线菌的初步鉴定及其抗菌活性测定

    Institute of Scientific and Technical Information of China (English)

    龙建友; 夏建荣

    2011-01-01

    cinerea Pets. , Alternaria alternate and Fusarium oxysporum were also greater than 80%. The inhibition rates of the fermentation products of GZ-204 and GZ-331 strains against the spore germination of Bipolaris sorokiniana and Cercospora sorghi were 97.8%, 98.2%, 99. 5% and 94. 6%, respectively. Potting test showed that the protection effects of the fermentation products of GZ-204 and GZ-331 strains on wheat powdery mildew were 78.8% and 87. 1%, and their cure effects were 62.4% and 68.5%, respectively. Field test showed that the control effects of 200 times fermentation liquids of GZ-204 and GZ-331 strains on wheat powdery mildew were 50.5% and 69.2%, respectively. [ Conclusion ] The research provided the reference for the development-of new pesticides with actinomycetes as the resource.