Fitopatologia Brasileira最新文献

{"title":"Identificação de fontes de resistência à ferrugem da folha do trigo em acessos de Aegilops tauschii","authors":"Â. B. Almeida, M. S. Chaves, S. Brammer, M. I. Baggio","doi":"10.1590/S0100-41582007000400011","DOIUrl":"https://doi.org/10.1590/S0100-41582007000400011","url":null,"abstract":"In Brazil, losses caused by wheat leaf rust (Puccinia triticina) occur annually. The widespread incidence in the different producing areas varies in intensity, depending on climatic conditions, level of genetic resistance of the cultivars and efficacy of chemical control. The use of resistant cultivars is the most efficient control method, and the genes conferring resistance to leaf rust fungus are denominated Lr. Several of these genes have already been identified and mapped. Some of them were mapped directly in hexaploid wheats, while others were initially found in related species, with lower ploidy level and later transferred to cultivated wheat. Among related species, Aegilops tauschii, the diploid species donor of the D genome of cultivated wheat, is indicated as an important source of resistance genes to leaf rust. The objective of this work was to evaluate the resistance of A. tauschii accessions from the Active Germplasm Bank of Embrapa Trigo (BAG - Passo Fundo, RS) to leaf rust, in order to incorporate this resistance in commercial varieties. The reaction to race SPJ-RS of Puccinia triticina was evaluated in forty accessions of A. tauschii and 25% (10 accessions) were resistant. The data obtained in this study can help in choosing resistant accessions to be used as parents in breeding programs in order to increase resistance to the pathogen.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"208 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120838877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Incidência e severidade de cancro cítrico em laranja 'Pêra Rio' sob condições de controle químico e proteção com quebra-vento","authors":"Franklin Behlau, J. B. Júnior, A. B. Filho, R. P. L. Júnior","doi":"10.1590/S0100-41582007000400005","DOIUrl":"https://doi.org/10.1590/S0100-41582007000400005","url":null,"abstract":"The objective of this work was to study citrus canker incidence and severity under natural conditions in an orchard of 'Pera Rio' sweet orange planted in Ourizona county, northwest of Parana State, Brazil. Chemical control, by using copper sprays, and windbreak protection were evaluated to reduce citrus canker incidence and severity on leaves. Levels of disease incidence were determined monthly by rating diseased leaves. Severity was evaluated monthly by using specific diagrammatic scales. Levels of severity were calculated considering just the diseased leaves assessed. Data were plotted on temporal progress curves and analyzed regarding the standardized area under disease progress curve (AUDPC*). The coefficient of determination (R2) between incidence and severity levels was also determined. Whereas copper sprays significantly reduced citrus canker on leaves, windbreak did not contribute significantly to disease control. After 29 assessments, plants submitted to frequent copper sprays showed AUDPC* values for citrus canker incidence 43.5% lower than those observed on plants not protected with chemical sprays. The same result was observed for citrus canker severity. After 18 assessments, plants sprayed with copper showed AUDPC* values for severity 37.1% lower than for check plants. In both years, the values of R2 between incidence and severity levels were higher than 0.80 (p<0.01).","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115175348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Control of late blight in industrial tomato with fungicide and potassium silicate","authors":"H. Duarte, L. Zambolim, F. Rodrigues","doi":"10.1590/S0100-41582007000300012","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300012","url":null,"abstract":"The aim of this study was to test the effect of fungicides and potassium silicate sprays on the control of late blight (Phytophthora infestans) of industrial tomato. The fungicides were applied according to the Wallin forecast system (FS) and on the weekly calendar. The experiment was carried out in a completely randomized block design with six treatments and four replications. The treatments (T) were: T1 - control; T2 - dimethomorph + chlorothalonil (disease severity values - DSV = 10) + metiram; T3 - metalaxyl-M + chlorothalonil (DSV = 10) + metiram (metiram was sprayed weekly when the DSV did not reach the required value for the treatment); T4 - calendar: dimethomorph + chlorothalonil, mancozeb, metalaxyl-M + chlorothalonil and chlorothalonil, alternated weekly; T5 and T6 - potassium silicate (5 and 15 g/L), respectively. The severity of late blight was evaluated according to a scale from 0 to 100 %. The final disease severity was 100; 2.6; 12.3; 5.5; 97.6 and 96 %, respectively, on the treatments T1, T2, T3, T4, T5 and T6. Disease severity was 93 %, less on the treatments that received the application of fungicides compared to the control. The FS (treatment 2) showed better results than treatment 3. The treatment 2, based on the FS, showed efficiency comparable to the weekly calendar (treatment 4) with yield of 62.103,73 and 52.473,33 kg/ha, respectively. These yields were superior compared to the other treatments. The applications of potassium silicate did not differ from the control. This indicates the inefficiency of this product in the control of late blight.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126508346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of Fingeriana dubia cavichioli transmitting Xylella fastidiosa to citrus","authors":"P. Yamamoto, M. R. Felippe, A. C. Caetano, A. L. Sanches, J. Lopes","doi":"10.1590/S0100-41582007000300014","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300014","url":null,"abstract":"Primeiro relato de Fingeriana dubia Cavichioli transmitindo Xylella fastidiosa para Citros Este trabalho relata, pela primeira vez, a transmissão da bactéria Xylella fastidiosa, agente causal da clorose variegada dos citros, por Fingeriana dubia Cavichioli (Hemiptera: Cicadellidae: Cicadellinae). Uma planta de três testadas mostrou-se infectada e apresentou sintomas típicos da CVC aproximadamente 9 meses após a inoculação por esta espécie de cigarrinha.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124649939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sclerotium rolfsii leaf spot on Anthurium plowmanii","authors":"C. Bastos","doi":"10.1590/S0100-41582007000300015","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300015","url":null,"abstract":"Sclerotium rolfsii leaf spot on Anthurium plowmanii Anthurium plowmanii is reported for the first time as a host of Sclerotium rolfsii in the State of Para, Brazil. O genero Anthurium Schott (Araceae) compreende mais de 600 especies, normalmente herbaceas, epifitas, nativas da America tropical, conhecidas popularmente por Anturio (Tombolato, A.F.C. Cultivo comercial de plantas ornamentais. Campinas SP. IAC. 2004). Em junho de 2006 foram observadas lesoes em folhas de Anthurium plowmanii Croat na Estacao de Recursos Geneticos “Jose Haroldo”, municipio de Marituba PA. Os sintomas caracterizavam-se por manchas de coloracao pardo-escura, sem bordos definidos, necroticas, de tamanho variavel. Na face inferior da folha, verificava-se crescimento micelial branco e presenca de numerosos esclerodios pequenos, arredondados, de cor branca no inicio e depois progredindo para pardo-escura. Em estadio mais avancado da infeccao, ocorriam rasgaduras das folhas. O isolamento do agente etiologico foi efetuado a partir de fragmentos do tecido foliar de amostras com sintomas da doenca e pelo processo direto de isolamento, retirando-se esclerodios com estilete esterilizado e transferindo-os para tubos de ensaio com BDA, que foram incubados a 25±1 °C, em ausencia de luz. Os isolamentos produziram culturas puras que caracterizaram pelo desenvolvimento de um micelio de coloracao branca. O crescimento do fungo em placas de Petri contendo BDA resultou em uma massa micelial algodonosa de coloracao branca e formacao de numerosos esclerodios arredondados de 0,5 – 1,5 mm de diâmetro, de coloracao branca no inicio e, posteriormente, pardo-escura, tipicos de Sclerotium rolfsii Sacc. (Figura 1A). Os testes de patogenicidade foram realizados em plantas de A. plowmanii mantidas em casa-devegetacao. A inoculacao consistiu na deposicao de discos de micelio de 5 mm de diâmetro na superficie de folhas, sem ferimentos ou previamente feridas com auxilio de estilete esterilizado, e submetidas a câmara umida. Como controle foram usados discos de BDA. Apos tres ou quatro dias, foi observado o inicio do desenvolvimento das lesoes nas folhas inoculadas com e sem ferimento. Posteriormente, as lesoes atingiram tamanho variado (Figura 1B), sendo o patogeno reisolado dos tecidos infectados e comparado ao isolado original, completando-se assim os postulados de Koch. O patogeno foi identificado como S. rolfsii com base nas caracteristicas morfologicas das colonias de culturas e dos esclerodios. Nao foram encontrados registros anteriores sobre a ocorrencia de S. rolfsii causando mancha foliar em A. plowmanii, embora no Brasil o patogeno ja tenha sido verificado causando murcha e podridao de raizes em Anthurium spp. (Mendes et al., Fungos em Plantas no Brasil. Brasilia DF. EMBRAPA. 1998). Recebido 12 Fevereiro 2007 Aceito 17 Maio 2007 FB 7013 FIG. 1 – A. Colonia de Sclerotium rolfsii em BDA, com esclerodios; B. Sintomas do patogeno em folha de Anthurium plowmanii, 6 dias apos inoculacao artificial. ","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128677060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seleção de extratos vegetais para indução de resistência e ativação de respostas de defesa em cacaueiro contra a vassoura-de-bruxa","authors":"M. Resende, J. D. C. B. Costa, F. R. Cavalcanti, P. J. R. Júnior, Fabrício Rabelo Camilo","doi":"10.1590/S0100-41582007000300005","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300005","url":null,"abstract":"Objetivou-se encontrar novos indutores de resistencia contra a vassoura-de-bruxa (Crinipellis perniciosa) do cacaueiro (Theobroma cacao), com eficacia igual ou superior a aquela conferida pelo indutor de resistencia padrao, acibenzolar-S-metil, e estudar possiveis respostas de defesa ativadas no cacaueiro por esses eliciadores mais eficazes. Foram testados extratos de varias plantas, principalmente, nativas do cerrado mineiro, bem como extratos provenientes de outras especies cultivadas. Verificou-se que extratos aquosos produzidos a partir de ramos de lobeira (Solanum lycocarpum) com sintomas de vassoura-de-bruxa induziram protecao de mudas de cacaueiros contra a mesma doenca em nivel estatisticamente similar a protecao conferida pelo ASM. O extrato aquoso e fervido de lobeira, aqui denominado VLA, nao foi toxico in vitro, pelo contrario, induziu maior crescimento do fungo C. perniciosa em BDA, quando comparado a testemunha (crescimento em BDA puro). Quando se quantificou a atividade de proteinas relacionadas a patogenese (quitinase e b-1,3-glucanase) estimuladas por VLA e ASM (como padrao), observou-se que ambos os tratamentos induziram maiores atividades de peroxidase, quitinase e b-1,3-glucanase em mudas de cacaueiros, comparados as respectivas testemunhas, no periodo de 4 a 18 dias apos a pulverizacao (DAP). Tambem o teor de lignina aumentou em plantas tratadas com VLA ou ASM, principalmente aos 18 DAP.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133252763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Método para inoculação de ferrugem da cana-de-açúcar em segmentos de folhas","authors":"Ely Oliveira Garcia, M. Casagrande, Alejandro Mario Rago, Nelson Sidnei Massola","doi":"10.1590/S0100-41582007000300011","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300011","url":null,"abstract":"The reaction of sugarcane to Puccinia melanocephala Syd. & P. Syd. populations is intensely influenced by environmental conditions, make it difficult to conduct field evaluations of genotypes. This work aimed to develop a method for rust inoculation in leaf segments. The segments were obtained from 30-day-old plants of the susceptible variety SP70-1143. These were inoculated (2 x 104 viable spores/mL) and kept in test tubes. The treatments consisted of different incubation conditions, considering the variables (i) use or not of wet chamber after the inoculation; (ii) immersion of ¼ or ¾ of the section in the liquid contained in the test tube and; (iii) addition or not of benzimidazole in the water of the tube. The best treatment consisted of immersion of ¾ of the section in test tubes containing water, with no moist chamber after the inoculation. After incubation (21 °C ± 1oC, 12 h of photoperiod) the sections remained viable for 20 days and showed good rust development. The method showed similar results when compared to the inoculation of whole plants of 3 varieties, making it possible to discriminate efficiently their reactions to rust.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128659913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fruit blotch of watermelon in Roraima.","authors":"Bernardo de Almeida Halfeld-Vieira, K. L. Nechet","doi":"10.1590/S0100-41582007000300016","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300016","url":null,"abstract":"","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129369996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predominância de begomovírus em tomateiros na região produtora da Ibiapaba, Ceará, e sua detecção natural em plantas daninhas","authors":"Luciana S.E.P. Arnaud, C. D. G. Santos, J. A. A. Lima, F. A. A. Feitosa","doi":"10.1590/S0100-41582007000300009","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300009","url":null,"abstract":"Tomato, Lycopersicon esculentum Mill., is an important vegetable in Brazil but presents serious problems concerning pathogen infections, mainly viruses. The viruses infecting tomato in Brazil belong to the genera Begomovirus, the most common and Potyvirus, Cucumovirus, Tospovirus and Tobamovirus. In the state of Ceara, although there are reports about the incidence of different viruses in plantations of tomato in the Chapada da Ibiapaba, the main producer of the state, there is a lack of information on the current situation of begomovirus in that region. The present work aimed to investigate the occurrence of begomovirus in tomato plantations of Ibiapaba region; to verify the presence of infected weeds; and to evaluate artificial transmission of begovomovirus from tomatoes or weeds to tomatoes. Serological tests and PCR revealed the presence of begomovirus in 'Alambra', 'Densus', 'Monalisa', 'Santa Clara', Sheila', 'Sofia', 'Raisa-N' and 'TY- Fanny' cultivars and hybrids most cultivated in the sampled counties. Besides begomovirus, Cucumber mosaic virus (CMV) and Potato virus Y (PVY) were also detected in the region. The weeds species Amaranthus spinosus, A. viridis, Ageratum conyzoides and Bidens pilosa were found to be hosts of begomovirus hosts. The virus was transmitted by grafting and mechanical transmission among tomato plants. Begomovirus transmission from infected weeds to tomato plants occurred by grafting. The survey revealed that begomovirus was predominant in the tomato plantations in the Ibiapaba region and that the weeds can be sources of begomovirus to tomato plantations.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"235 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124588547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensibilidade de Xanthomonas axonopodis pv. citri ao cobre e mancozeb","authors":"Luciana Meneguim, Dirlene A.M.F. Rinaldi, Ana C. Agulheiro Santos, Ludmila S. Rodrigues, M. D. Silva, M. G. Canteri, R. P. L. Júnior","doi":"10.1590/S0100-41582007000300010","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300010","url":null,"abstract":"Citrus canker, caused by Xanthomonas axonopodis pv. citri (Hasse) Vauterin et al. 1995 (Xac), is one of the most important problems for citrus production around the world. Spraying with copper compounds is a major measure for control of the disease. The objective of this study was to determine the sensitivity of Xac strains from the State of Parana, Brazil, to copper as well as to a mixture of copper with mancozeb. The highest copper concentration where Xac grew was 50 µg/mL. However, 45.5 % of the bacterial strains from orchards with regular sprays of copper compounds grew in the presence of 50 µg/mL of copper. In contrast, only 13.4 % of the strains from citrus orchards that never received copper sprays grew in such a copper concentration . Mixing mancozeb with copper increased the tolerance of Xac to copper. Therefore, the recommendation of mancozeb mixed with copper for control of the citrus canker bacterium should be reviewed.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131767506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}