Fitopatologia Brasileira最新文献_第6页

Epidemiological analysis of clones and cultivars of potato in soil naturally infested with Ralstonia solanacearum Biovar 2. 马铃薯2号自然侵染土壤无性系及品种的流行病学分析。

Fitopatologia Brasileira Pub Date : 2007-06-01 DOI: 10.1590/S0100-41582007000300001

J. Silveira, V. Duarte, M. G. Moraes, C. A. Lopes, J. M. Fernandes, V. Barni, J. Maciel

{"title":"Epidemiological analysis of clones and cultivars of potato in soil naturally infested with Ralstonia solanacearum Biovar 2.","authors":"J. Silveira, V. Duarte, M. G. Moraes, C. A. Lopes, J. M. Fernandes, V. Barni, J. Maciel","doi":"10.1590/S0100-41582007000300001","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300001","url":null,"abstract":"Os objetivos deste estudo foram avaliar o progresso da murcha bacteriana, a resistencia do clone MB 03, selecionado para a raca 1 em Brasilia, e detectar a presenca do patogeno em tuberculos colhidos de plantas assintomaticas. Durante a primavera (setembro a final de novembro no hemisferio sul) de 1999 e 2000, 14 cultivares ou clones foram cultivados num campo naturalmente infestado com R. solanacearum biovar 2, em Caxias do Sul, RS. O numero de plantas com sintomas de murcha foi registrado semanalmente para a obtencao da curva de progresso da doenca. Para comparar a resistencia dos genotipos de batata a murcha bacteriana foi calculada a area sob a curva de progresso da doenca. Dentre os modelos avaliados para ajuste das curvas, o modelo logistico foi o que melhor se ajustou. Ao final das avaliacoes, em cada periodo de cultivo, os tuberculos produzidos por plantas assintomaticas foram coletados e armazenados ate o inicio da brotacao, quando foram submetidos a testes para detectar a presenca de R. solanacearum. A cultivar Cruza 148 e o clone MB 03 foram os genotipos mais resistentes, mas ambos apresentaram tuberculos com infeccoes latentes. As implicacoes epidemiologicas da incidencia de R. solanacearum raca 3 em lavouras de batata, bem como da resistencia de determinados genotipos que podem propiciar tuberculos com infeccoes latentes, sao aspectos de importância para o manejo integrado da murcha bacteriana no RS.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"2010 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":"121542954","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}

引用次数: 8

Respostas de genótipos de Coffea spp. a diferentes populações de Meloidogyne exigua 咖啡基因型对不同根结线虫种群的响应

Fitopatologia Brasileira Pub Date : 2007-06-01 DOI: 10.1590/S0100-41582007000300004

Rodrigo Vieira da Silva, R. L. Oliveira, A. Pereira, Dalila J. Sêni

{"title":"Respostas de genótipos de Coffea spp. a diferentes populações de Meloidogyne exigua","authors":"Rodrigo Vieira da Silva, R. L. Oliveira, A. Pereira, Dalila J. Sêni","doi":"10.1590/S0100-41582007000300004","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300004","url":null,"abstract":"In Brazil, Meloidogyne exigua is one of the most important pathogens that attack coffee plants. Morphological, biochemical, molecular and physiological variabilities have been observed in M. exigua, but the expression of these variabilities in coffee genotypes is not well known. To evaluate the effect of M. exigua on 25 Coffea spp. genotypes, populations exhibiting distinct esterase phenotypes and host suitability variations were selected. Thus, coffee seedlings at the stage of 3-4 sets of two leaves were inoculated with 5000 eggs of either population, with each treatment including six replicates. The evaluation occurred 110 days after inoculation, by counting galls and eggs per root system and measuring root fresh weight. According to the genotypes' reaction, three groups of Coffea spp. were detected: fourteen expressed susceptible reaction, six segregated and five were immune to M. exigua populations. The segregating genotypes behaved in a different way in relation to the four populations. Thus, the utilization of different populations showing this variability is fundamental for a breeding program that aims to develop resistant cultivars.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"8 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":"126367478","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}

引用次数: 16

Análise de risco das mudanças climáticas globais sobre a sigatoka-negra da bananeira no Brasil 巴西香蕉黑叶斑病全球气候变化风险分析

Fitopatologia Brasileira Pub Date : 2007-06-01 DOI: 10.1590/S0100-41582007000300003

R. Ghini, E. Hamada, R. R. V. Gonçalves, L. Gasparotto, J. R. Pereira

引用次数: 35

Caracterização de solos de pernambuco quanto à supressividade a Pectobacterium carotovorum subsp. carotovorum 伯南布哥土壤对胡萝卜果胶杆菌亚种的抑制特性。carotovorum

Fitopatologia Brasileira Pub Date : 2007-06-01 DOI: 10.1590/S0100-41582007000300006

Indira del C.M. Alvarado, S. J. Michereff, R. D. L. R. Mariano, Adriano Márcio Freire Silva, C. Nascimento

{"title":"Caracterização de solos de pernambuco quanto à supressividade a Pectobacterium carotovorum subsp. carotovorum","authors":"Indira del C.M. Alvarado, S. J. Michereff, R. D. L. R. Mariano, Adriano Márcio Freire Silva, C. Nascimento","doi":"10.1590/S0100-41582007000300006","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300006","url":null,"abstract":"The soft-rot caused by P. carotovorum subsp. carotovorum (Pcc) is a limiting factor for vegetable harvests in Pernambuco State. Soil characteristics and environmental factors may influence Pcc population and development of soft-rot. This work aimed to evaluate the extinction rate of Pcc population in 24 soil samples of Pernambuco and analyze physical, chemical and microbiological soil characteristics associated with suppressiveness or conduciveness for the pathogen. In the study of soil influence on Pcc population a rifampicin-resistant mutant was utilized (Pcc127Rif). The extinction rate of population (TERP) was calculated and ranged from 0.0547 to 0.6327 log (CFU)/d. Six soils showed suppressiveness for Pcc127Rif while five presented conduciveness. The soil groups based on the TERP of Pcc127Rif did not correlate with municipalities, types of vegetation cover at the sampling time or soil textural classes. Considering all soils, there were no significant correlations (P<0.05) among TERP of Pcc127Rif and chemical, physical and microbiological characteristics of soils. Considering the six most suppressive soils, the TERP of Pcc127Rif significantly correlated with apparent soil density (r = 0.76), total bacterium population (r = 0.82) and Bacillus sp. (r = 0.80). The Bacillus sp. population correlated with apparent density, but not with total bacterium population. Considering the five most conducive soils there was correlation between TERP of Pcc127Rif and Bacillus sp. population (r = -0.86).","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"30 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":"129774374","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}

引用次数: 4

Etiologia da podridão do coleto de Brachiaria brizantha em pastagens da amazônia 亚马逊草原brizantha腕鱼coleto腐病的病因

Fitopatologia Brasileira Pub Date : 2007-06-01 DOI: 10.1590/S0100-41582007000300013

M. L. R. Duarte, F. Albuquerque, Rosa Maria V. Sanhueza, J. R. Verzignassi, Norio Kondo

引用次数: 12

A novel postharvest rot of okra pods caused by Rhizoctonia solani in Brazil 巴西一种由枯丝核菌引起的秋葵荚果采后腐病

Fitopatologia Brasileira Pub Date : 2007-06-01 DOI: 10.1590/S0100-41582007000300008

G. Henz, C. A. Lopes, A. Reis

{"title":"A novel postharvest rot of okra pods caused by Rhizoctonia solani in Brazil","authors":"G. Henz, C. A. Lopes, A. Reis","doi":"10.1590/S0100-41582007000300008","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300008","url":null,"abstract":"Okra pods with unusual brown lesions and rot were collected in a local supermarket in Brasilia DF. The objective of this paper was to characterize the causal agent, to fulfill Koch's postulates and to determine some conditions conducive to disease. The pathogen was identified as Rhizoctonia solani based on morphological characteristics which fitted the fungus description, such as pale to brown hyphae, with nearly right-angled side branches constricted at the base, hyphal cells 6-10 µm wide with a septum near the base. Five isolates were obtained from infected pods and identified as AG 1-IB anastomosis group. Wounded or unwounded okra pods cv. Santa Cruz 47 were inoculated with mycelium disks of R. solani and kept in humid chambers at 12 oC or 25 oC. After seven days at 25 oC, both wounded and unwounded pods were completely rotted and brown, while those kept at 12 oC showed small lesions ranging from 0.6 to 1.0 mm only in wounded pods. The pathogen was able to grow in different materials used for assembling crates and packs of horticultural products, such as pinewood, corrugated carton, plastic, Styrofoam and newspaper sheets when kept in humid chambers (24 oC, 96 % RH). The disease occurrence can be related to careless handling practices and to the transmission of R. solani propagules by infected plant debris or soil particles. This is the first report of Rhizoctonia solani causing postharvest rot in okra pods in Brazil.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"183 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":"114742349","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}

引用次数: 5

Caracterização de isolados de Rhizoctonia spp. e identificação de novos grupos de anastomose em jardim clonal de eucalipto 桉树无性系花园根核菌分离株的鉴定及吻合新类群的鉴定

Fitopatologia Brasileira Pub Date : 2007-06-01 DOI: 10.1590/S0100-41582007000300007

E. Sanfuentes, A. C. Alfenas, L. A. Maffia, R. G. Mafia

{"title":"Caracterização de isolados de Rhizoctonia spp. e identificação de novos grupos de anastomose em jardim clonal de eucalipto","authors":"E. Sanfuentes, A. C. Alfenas, L. A. Maffia, R. G. Mafia","doi":"10.1590/S0100-41582007000300007","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300007","url":null,"abstract":"Rhizoctonia spp. cause shoot and leaf blight of eucalyptus in clonal hedges as well as cuttings. Despite the importance of Rhizoctonia spp. to eucalyptus, little is known about their diversity. Thus, we characterized isolates and report new anastomosis groups in a eucalyptus clonal hedge. Isolates obtained at different stages of cutting propagation were characterized according to the number of nuclei in vegetative cells, grouped by morphological characteristics of the colony, anastomosis group, and thiamine auxotrophism. The isolates were also evaluated for virulence on eucalyptus and effect of temperature on their mycelial growth. No correlation between morphological grouping and anastomosis reaction was detected. A wide range of isolates, predominantly binucleate, forms the population of Rhizoctonia spp. present in the soil of clonal hedges, which differed in virulence to eucalyptus. Binucleate and multinucleate isolates had similar growth features at different temperatures, with an optimum growth rate between 25-30 oC. Isolates of R. solani AG2-2 IIIB and binucleate isolates of Rhizoctonia spp., AG-P and AG-O, as agents of cutting rot, and binucleate isolates AG-A and AG-L in the soil of eucalyptus clonal hedge are reported for the first time.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"1 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":"131263394","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}

引用次数: 4

Indução de resistência em tomateiro por extratos aquosos de Lentinula edodes e Agaricus blazei contra Ralstonia solanacearum 香菇和蘑菇水提物对番茄抗茄青霉的抗性诱导

Fitopatologia Brasileira Pub Date : 2007-06-01 DOI: 10.1590/S0100-41582007000300002

R. F. Silva, S. F. Pascholati, I. P. Bedendo

{"title":"Indução de resistência em tomateiro por extratos aquosos de Lentinula edodes e Agaricus blazei contra Ralstonia solanacearum","authors":"R. F. Silva, S. F. Pascholati, I. P. Bedendo","doi":"10.1590/S0100-41582007000300002","DOIUrl":"https://doi.org/10.1590/S0100-41582007000300002","url":null,"abstract":"This work deals with the effect of aqueous extracts from the mushrooms Lentinula edodes and Agaricus blazei and the inducer of resistance acibenzolar-S-methyl (ASM) on the control of bacterial wilt in tomato (Lycopersicon esculentum Mill.), as well as investigating changes in enzyme activities. Aqueous extracts of the mushrooms and ASM were tested for inhibition of bacterial growth in vitro. Plants were treated with different concentrations of the extracts and with ASM two days before inoculation in greenhouse conditions. The evaluations were based upon disease severity and activity of some enzymes. In general, the isolates of A. blazei and L. edodes, as well as ASM, did not inhibit in vitro bacterial growth. In treated plants, the isolate Le-96/17 10 % (v/v) of L. edodes and ASM significantly reduced bacterial wilt. Chitinase, phenylalanine ammonia-lyase and polyphenoloxidase activities were not changed for most of the treatments; however, increased chitinase activity was verified in plants treated with ASM. The ASM, Abl-26 and Le-96/17 treatments increased peroxidase activity in plants and, based upon the results, L. edodes mushroom and ASM both exhibit potential to reduce bacterial wilt in tomato plants, probably by inducing resistance.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"40 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":"125654279","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}

引用次数: 37

Resistência de Progênies de Café Catimor à Ferrugem 卡蒂莫咖啡后代的抗锈蚀性

Fitopatologia Brasileira Pub Date : 2007-04-01 DOI: 10.1590/S0100-41582007000200005

Mauro J. N. Costa, L. Zambolim, E. T. Caixeta, A. Pereira

{"title":"Resistência de Progênies de Café Catimor à Ferrugem","authors":"Mauro J. N. Costa, L. Zambolim, E. T. Caixeta, A. Pereira","doi":"10.1590/S0100-41582007000200005","DOIUrl":"https://doi.org/10.1590/S0100-41582007000200005","url":null,"abstract":"To study the performance of Catimor genotypes, field tests were done to evaluate their productive capacity and rust incidence, while horizontal resistance of seedlings to race II of Hemileia vastatrix was tested in the greenhouse. The reaction to the pathogen was evaluated on a scale of 0 to 9 where: 0 to 3 = resistant plants and 4 to 9 = susceptible plants. The components of quantitative resistance evaluated were: infection frequency, sporulation, lesioned foliar area, incubation period and latent period. Progenies UFV 5550, UFV6861, UFV 6870, UFV6831 and UFV 6834 showed similar productivity to the Catuai cultivar (P < 0.05). Progenies UFV 5530, UFV 5451, UFV 5550, UFV 6903 and UFV 5464 produced no diseased plants. The descendents of the progenies in this study varied greatly for rust reaction, with continuing variation from full resistance to high susceptibility, with the majority at intermediary levels. This indicates the presence of quantitative resistance in these genotypes. Compared to the Catuai cultivar, it can be concluded that the studied genotypes had quantitative resistance, with the average number of lesions and lesioned foliar area 13 to 21 times less, respectively, on UFV 6866. The sporulation of UFV 6870 reached 0.1, a very low score if compared to Catuai's score of 3.6. The incubation period of the studied genotypes varied from 18 to 36 days and the latent period from 20 to 46 days. Compared to the Catuai Vermelho IAC 15 cultivar, it can be concluded that the great majority of Catimor genotypes studied had quantitative resistance.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127356954","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}

引用次数: 11

Critical-point yield model to estimate yield damage caused by Cercospora zea-maydis in corn 临界点产量模型，用于估算玉米中 Cercospora zea-maydis 造成的产量损失

Fitopatologia Brasileira Pub Date : 2007-04-01 DOI: 10.1590/S0100-41582007000200003

E. M. Reis, Jones A.P. Santos, Marta Maria Casa Blum

{"title":"Critical-point yield model to estimate yield damage caused by Cercospora zea-maydis in corn","authors":"E. M. Reis, Jones A.P. Santos, Marta Maria Casa Blum","doi":"10.1590/S0100-41582007000200003","DOIUrl":"https://doi.org/10.1590/S0100-41582007000200003","url":null,"abstract":"A model to estimate damage caused by gray leaf spot of corn (Cercospora zea-maydis) was developed from experimental field data gathered during the summer seasons of 2000/01 and during the second crop season [January-seedtime] of 2001, in the southwest of Goias state. Three corn hybrids were grown over two seasons and on two sites, resulting in 12 experimental plots. A disease intensity gradient (lesions per leaf) was generated through application, three times over the season, of five different doses of the fungicide propiconazol. From tasseling onward, disease intensity on the ear leaf (El), and El - 1, El - 2, El + 1, and El + 2, was evaluated weekly. A manual harvest at the physiological ripening stage was followed by grain drying and cleaning. Finally, grain yield in kg.ha-1 was estimated. Regression analysis, performed between grain yield and all combinations of the number of lesions on each leaf type, generated thirty linear equations representing the damage function. To estimate losses caused by different disease intensities at different corn growth stages, these models should first be validated. Damage coefficients may be used in determining the economic damage threshold.","PeriodicalId":211183,"journal":{"name":"Fitopatologia Brasileira","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126462829","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}

引用次数: 15