Assays were done under greenhouse conditions in order to evaluate the effect of pyraclostrobin (0.0375, 0.0750 and 0.150 mL.L -1 ) and acibenzolar-S-methyl (ASM) (0.025 g.L -1 ) in common bacterial blight on leaves of snap beans cultivar Bragança. These chemicals were sprayed at three different times: five days before; five days before + five days after; and five days after leaf inoculation with an isolate of Xanthomonas axonopodis pv. phaseoli. They were determinate the levels of polyphenoloxidase, peroxidase and total soluble proteins on inoculated and non-inoculated leaves of snap beans sprayed with pyraclostrobin (0.075 g.L -1 ) and ASM (0.025 g.L -1 ). All concentration of pyraclostrobin and ASM reduced the area under the disease progress curve (AUDPC) on leaves of snap beans, and the least AUDPC value was observed when this products were sprayed five days before + five days after inoculation. Higher levels of polyphenoloxidase, peroxidase and the total soluble proteins were observed on leaves sprayed with pyraclostrobin or ASM. Key words: Phaseolus vulgaris, Xanthomonas axonopodis pv. phaseoli, protein ResumoEnsaios foram conduzidos sob condições de casa-de-vegetação para avaliar o efeito de pyraclostrobin (0,0375; 0.0750 e 0,150 mL.L -1 ) e acibenzolar-S-methyl (ASM) (0.025 g.L -1 ) sobre o crestamento bacteriano comum em folhas de feijão-vagem cultivar Bragança. Os produtos foram pulverizados em três diferentes períodos: cinco dias antes, cinco dias antes + cinco dias após e cinco dias após a inoculação dos folíolos com um isolado de Xanthomonas axonopodis pv. phaseoli. Foram determinados os teores de polifenoloxidase, peroxidase e proteínas solúveis totais em folhas inoculadas e não-inoculadas de feijão-vagem pulverizadas com pyraclostrobin (0,075 g.L-1) e ASM (0,025 g.L-1). Todas as concentrações de pyraclostrobin e ASM reduziram os valores da área abaixo da curva do progresso da doença (AUPDC) e o menor valor da AUPDC foi observado para a aplicação dos produtos cinco dias antes + cinco dias após a inoculação. Altos teores de polifenoloxidase, peroxidase e proteínas solúveis totais foram observados nas folhas pulverizadas com pyraclostobin e ASM. Palavras-chave: Phaseolus vulgaris, Xanthomonas axonopodis pv. phaseoli, proteína

A exploração da atividade biológica de compostos secundários presentes nas tinturas ou em óleos essenciais de plantas podem representar, ao lado da indução de resistência, mais uma forma potencial de controle de doenças em plantas cultivadas. O presente trabalho objetivou avaliar o potencial de tinturas de Lippia alba, Lippia sidoides, Mikania glomerata, Equisetum sp. e Hedera helix e óleos essenciais de Rosmarinus officinalis e Cinnamomum zeylanicum nas atividades in vitro, in vivo e na produção de proteínas na indução de resistência, em plantas de feijão vagem cultivar Bragança. Os resultados obtidos demonstraram que as tinturas de L. alba e L. sidoides e os óleos essenciais (R. officinalis e C. zeylanicum) apresentaram atividade in vitro aos isolados de Xanthomonas axonopodis pv. phaseoli. Todas as tinturas ensaiadas apresentaram menores valores do progresso da doença (AACPD), em relação à testemunha, merecendo destaque a tintura de L. alba, que estavam correlacionadas com os maiores teores de polifenoloxidase, peroxidase e proteínas solúveis totais, evidenciando uma possível indução de resistência. Os óleos essenciais não apresentaram diferença na AACPD e nem na indução de proteínas.

A soja (Glycine max L.) é principal cultura do agronegócio brasileiro e tornou-se a mais expressiva economicamente no país, tanto pelo aumento da área cultivada quanto pelas novas tecnologias disponibilizadas aos produtores. As doenças podem ter origens fúngicas, bacterianas e viróticas e neste estudo destaca-se a murcha-de-Curtobacterium, causada pela bactéria gram-positiva Curtobacterium flaccumfaciens pv. flaccumfaciens. O sintoma é caracterizado por uma mancha bacteriana marrom nas folhas de soja. O objetivo do trabalho foi expor os aspectos do patógeno C. flaccumfaciens pv. flaccumfaciens na cultura da soja, discutindo as principais estratégias de controle para minimizar os problemas com a doença. Deve-se ressaltar que, ao obter conhecimento sobre os aspectos agronômicos e os fatores limitantes da cultura da soja em relação à bactéria e seus principais aspectos biológicos, será possível a adoção das melhores técnicas de manejo da doença. Conclui-se que a busca por cultivares resistentes é de extrema importância no manejo da doença, uma vez que outros métodos de controle são pouco eficientes. Para alcançar o controle da mancha bacteriana marrom na cultura da soja é necessário a adoção conjunta de todas as técnicas de controle empregadas de forma unificada (manejo integrado da doença) visando a manutenção da população de C. flaccumfaciens pv. flaccumfaciens em baixos níveis.   Palavras-chave: Mancha Bacteriana Marrom. Controle de Doenças. Glycine max L. Distribuição.   Abstract Soybean (Glycine max L.), is the main crop of Brazilian agribusiness, it has become the most economically important in the country, both due to the increase in cultivated area and the new technologies available to farmers. Diseases can have several origins, including fungal, bacterial and virotic, but in this study, we will talk about curtobacterium wilt, caused by a gram-positive bacterium Curtobacterium flaccumfaciens pv. flaccumfaciens, responsible for brown bacterial wilt on soybean plants. The objective of this work was to expose the aspects of the pathogen Curtobacterium flaccumfaciens pv. flaccumfaciens in soybean crops, discussing the main control strategies to minimize problems caused by this disease. It should be emphasized that gaining knowledge about the agronomic aspects and limiting factors of soybean crop in relation to the pathogen is necessary to reach the best management of the disease. We concluded that the search for resistant cultivars is extremely important for disease management, since other control methods are inefficient. To achieve the control of bacterial tan spot in soybean crop, it is necessary to joint adoption of all the control techniques used in a unified way (disease integrated management) aiming at maintaining the population of Curtobacterium flaccumfaciens pv. flaccumfaciens at low levels.   Keywords: Bacterial Tan Spot. Disease Control; Glycine max L. Distribution.

Corynespora cassiicola threatens soybean and cotton production in Brazil. The objective of this study was to evaluate cultural and morphological aspects of C. cassiicola isolated from soybean and cotton of different Brazilian regions, in culture media. The isolates were grown in PDA (Potato Dextrose Agar) and V8 juice agar media. The characteristics evaluated were: color, aspect, and growth rate of mycelia, as well as production and dimension of conidia, and number of septa per conidium. Culture media and isolates were compared using the Kruskal-Wallis or Tukey’s test at 5% significance level. The mycelia of the isolates were predominantly dark gray and light brown. C. cassiicola isolates grew better in V8 juice agar medium, presenting a higher mycelial growth rate. In PDA medium, the production of conidia was higher in isolates from cotton, compared with soybean isolates. There was great variation in the production of conidia in V8 juice agar medium, regardless of the host origin. Conidia length and width varied for isolate and culture medium. The isolates of C. cassiicola coming from cotton presented a higher number of septa per conidium when grown in PDA medium. The morphological aspects of C. cassiicola vary depending on the host of origin and the culture medium.

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This study checked the severity and incubation period of isolates of Coryneporacassiicola (C.c) in soybean cultivars, as well verified whether the position of leaflets influences the susceptibility of the plant to target spot. The experiment was conducted in randomized block with 8 isolates of C.c and 8 soybean cultivars factorial scheme, with five repetitions each block. The plants were inoculated with suspension from 2x104 conidia mL-1. The number of lesions per leaf and the incubation period (IP) were evaluated. The ISO 4S isolate caused greater number of lesions in plants. BMX Potência RR, BMX Força RR, and NA 5909 RG had the lowest occurrence of lesions, while the cultivar BMX Elite IPRO showed the highest number of lesions. More lesions were detected in the lower leaf compared to the upper leaf of the plants. The longest IP was observed for ISO 4S in both leaflets, while the lowest IP for ISO 1A, 3A and 2A in the lower leaf, and for ISO 11S and 1S in the median leaf. For cultivars, significant difference in IP was observed only in the lower leaf, with the longest and shortest IP detected for BMX Elite IPRO and BRS 284, respectively. In general, the upper leaf of the plants presented the shortest IP while the lower leaf had the longest IP.

The present study aimed to isolate endophilic fungi from plant tissues (leaves, stems and roots) of beans, in addition to identifying them at the genus level. The experiment was conducted at IDR-Londrina. Bean samples were collected at the Londrina Research Station and at UENP-Bandeirantes. The leaves, stems and roots were separated, fragments of 5 mm diameter were cut and disinfested. They were later transferred to BDA culture medium. The plates were incubated at room temperature for seven days for growth of the microorganisms present. The presence and absence, colonization rate (TC) for each tissue and gender identification of fungi were evaluated. The experiment was conducted in a completely randomized design, with five replications. Forty-eight endophilic isolates were found, 13 in root, 17 in stem and 18 in leaf. CT ranged from 17-100% (leaf), 17-83% (stem) and 16-100% (root). The genus Alternaria sp. and Cladosporium sp. have greater specificity with the leaf and stem, Penicillium sp. root and stem. The genera Fusarium sp. and Aspergillus sp. are found in all organs, Curvularia sp., Nigrospora sp. and Thichoderma sp. demonstrated leaf specificity, Macrophomina sp. the root, and Colletotrichum sp. to the stem. Thus, the identified fungi present potential for future studies in their application in the biocontrol of various plant diseases.

Wheat seeds can be infested and/or infected by microorganisms that might cause deterioration of this propagation structure. The aim of this study was to evaluate the health quality of sixteen wheat genotypes grown in northern Paraná. Therefore, seeds of each genotype were submitted to the blotter test with 16 repetitions, 400 seeds per sample, for phytosanitary quality evaluation. The identification of the fungi was performed based on their morphological characteristics and quantified data. The results revealed variations in incidence, with 20 fungi genera in the analyzed samples. The fungi Rhizopus sp., Aspergillus sp., Penicillium sp. and Bipolaris sp. were found in 100% of the analyzed samples, while Mucor sp. and Alternaria sp. were in 89% and 78% of the samples, respectively. The main pathogens that cause diseases in the aerial part of wheat were not found, or were low incidence in all materials analyzed. The pathogens with the highest incidence associated with wheat seeds were groups of storage fungi and known to produce mycotoxins.