Este trabalho objetivou analisar o controle biológico do Colletotrichum musae em bananas por meio de Saccharomyces cerevisiae e Saccharomyces boulardii. Células de S. cerevisiae foram obtidas a partir do fermento de panificação Fleischmann ® . Células de S. boulardii foram obtidas a partir do medicamento Floratil ® . Utilizou-se um cacho de banana colhido de área orgânica, os frutos passaram por um processo de assepsia, em seguida foram tratados com células de S. cerevisiae, S. boulardii e ambas as leveduras na concentração de 2 g L -1 , após 24 horas inoculou-se o C. musae em três pontos por fruto. Para avaliar-se o efeito da concentração de células no tratamento o processo foi repetido, tratando-se os frutos com concentrações de 0; 0,5; 1; 2; 4 e 8 g L RESUMOS. cerevisiae e S. boulardii, avaliou-se a área lesionada, a cada 48 horas, por 14 dias. Também avaliou-se o halo de inibição e a produção de compostos voláteis, ambos in vitro, para analisar se há ocorrência de antagonismo. Observou-se que o tratamento com as leveduras reduz o progresso da doença, e que S. cerevisiae e S. boulardii apresentam maior eficiência na concentração de 5,5 e 6,3 g L -1 , respectivamente, apresentando redução de 48% e 35% do progresso da doença, respectivamente. Observou-se a formação de halo de inibição e produção de compostos voláteis, indicando que estas leveduras atuam por meio de antagonismo. Deste modo, estas leveduras são potencias agentes de controle biológico do C. musae. ABSTRACTThis study aimed to analyze the biological control of Colletotrichum musae in bananas by using Saccharomyces cerevisiae and Saccharomyces boulardii. Cells of S. cerevisiae were obtained from Fleischmann ® bread yeast. Cells of S. boulardii were obtained from the drug Floratil ® . A bunch of bananas collected from an organic area was used. Fruits underwent a process of asepsis and were then treated with cells of S. cerevisiae, S. boulardii and both yeasts at the concentration of 2 g L -1 ; after 24 hours, C. musae was inoculated in three points per fruit. To evaluate the effect of cell concentration on the treatment, the process was repeated, treating the fruits with concentrations of 0; 0.5; 1; 2; Heling, A.L.; Kuhn, O.J.; Stangarlin, J.R.; Henkemeier, N.P.; Coltro-Roncato, S.; Gonçalves, E.D.V. Biological control of anthracnose in the postharvest of manzano bananas using Saccharomyces spp. Summa Phytopathologica, v.43, n.1, p.49-51, 2017. 4 and 8 g L -1 of S. cerevisiae and S. boulardii; the injured area was evaluated at every 48 hours during 14 days. The inhibition halo and the production of volatile compounds were also evaluated, in vitro, to analyze whether there is antagonism. Treatment with these yeasts reduces the disease progress and S. cerevisiae and S. boulardii exhibit greater efficiency at the concentration of 5.5 and 6.3 g L -1 , respectively, leading to a reduction of 48% and 35% in the disease progress, respectively. We observed formation of inhibition halo and production of volatile compounds, indicating that these yeasts act ...

The aims of the study were to evaluate the control of botrytis in the soybean stem, spraying homeopathic solutions of Sulphur and Nosode of Macrophomina phaseolina in the dynamizations 6, 12, 24, 36 and 48CH. As additional treatment, we used distilled water and hydroalcoholic solution at 30% ethanol. In vitro tests were performed so as to analyze the number of micro-sclerotia and mycelial growth of the fungi, and in vivo tests to track the progress of the botrytis stem and the size of the lesion. The experimental design was in randomized blocks, with five replications. For the area under the mycelial growth curve (AUMGC) in the first test, there was no significant effect of Sulphur and Nosode of M. phaseolina. In vivo studies, comparing Sulphur with the control treatment, showed a reduction of 14 and 15% for the dynamizations of 12 and 48 CH, respectively. For the amount of micro-sclerotia of M. phaseolina, in the first test, Sulphur showed a reduction of up to 50%; Nosode of M. phaseolina showed no significant reduction of micro-sclerotia. In the second test, Nosode was not significant while Sulphur caused a reduction of up to 33%. For area under the disease progress curve (AUDPC), in both trials, the drugs proved to be ineffective. These results indicate the potential of these homeopathic remedies in controlling the fungus, M. phaseolina.

The objective of this study was to develop and validate a diagrammatic scale to evaluate the severity of spots on maize leaves caused by the fungus Diplodia macrospora. Severity ranged between the minimal (0.5%) and maximal (55%) limits of disease severity, and intermediate severity levels were defined according to the "Weber-Fechner stimulus response law". The proposed scale describes six levels of severity based on how much of the leaf is affected: 0.5%, 3%, 8%, 23%, 36%, and 55%. Validation was carried out by eight evaluators, four inexperienced and four experienced. They estimated the severity of disease in 60 maize leaves, with and without the proposed diagrammatic scale. A relationship was shown by regression analysis between estimated and actual severity, with and without the use of the scale. When both inexperienced and experienced evaluators used the scale, they were able to estimate disease severity more accurately and precisely.

Bean common bacterial blight reduces crop productivity and is difficult to control. However, biological control by yeast can be an efficient complementary measure in management. The objective was to evaluate the ability of Rhodotorula glutinis and Sporidiobolus johnsonii to reduce the severity of bean common bacterial blight. The cultivar used was IAPAR Tuiuiú. The first experiment was sown in March and repeated in October, in a 4 × 3 factorial scheme (zero, one, two and three applications and three treatments R. glutinis, S. johnsonii and Acibenzolar-S-Methyl (ASM)). For this purpose were evaluated the area under the disease progress curve (AACPD), number of pods per plant (NVP), number of grains per pod (NGV), thousand grain mass (MMG) and productivity. For the results of the March cultivation, due to the low temperature, the maximum severity of bean common bacterial blight was 8% and the applications of yeasts were not significant for AACPD. The isolate R. glutinis showed the highest average of productivity with two applications, being 1006.44 kg ha-1. For October cultivation, R. glutinis and S. johnsonii isolates reduced AACPD by 66.84 and 58.42%, respectively with three applications. For productivity, R. glutinis and S. johnsonii showed no difference between the number of applications. The ASM showed a productivity of 4418.56 kg ha-1 with three applications. The results indicate that the yeasts R. glutinis and S. johnsonii reduce the severity of bean common bacterial blight and the most appropriate number of applications are two for both isolates.

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