Coffee Science - v.14, n.1, 2019
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12058
Navegar
4 resultados
Resultados da Pesquisa
Item Applications of copper-based fungicides and infestations of Leucoptera coffeella (Guérin-Mèneville & Perrottet) in coffee plants(Editora UFLA, 2019-01) Sabino, Paulo Henrique de Siqueira; Silva, Gian Otávio Alves da; Silva, Adriano Bortolotti da; Carvalho, Geraldo AndradeThe present study aimed to evaluate the effects of applying fungicides with different sources of copper and of the number of applications on the occurrence of Leucoptera coffeella (Guérin-Menéville & Perrottet, 1842) (Lepidoptera: Lyonetiidae) and on the wax content on leaves in a coffee plantation. Four applications of fungicides were carried out, and the effects on the number of leaves mined by the insect and on the wax content on the leaf surface were evaluated. The copper- based fungicides increased the number of leaves mined by the leaf-miner and reduced the wax content on the coffee leaf surfaces in both periods studied.Item Infection process of Cercospora coffeicola in immature coffee fruits(Editora UFLA, 2019-01) Paula, Paulo Victor Augusto Azevedo de; Pozza, Edson Ampélio; Alves, Eduardo; Moreira, Silvino Intra; Paula, Júlio Cesar Azevedo; Santos, Leandro AlvarengaCercosporiosis is caused by Cercospora coffeicola and represents a very important coffee plants phytosanitary problem. Catuaí IAC 144 and Topázio cultivars at the F2 stage were inoculated with a conidial suspension. Samples were collected at 4, 8, 12, 24, 36, 48, 72, 96, and 168 hours after inoculation (hai) for scanning electron microscope studies. Fungal germination in epidermal surface occurred four hai; penetration only through epidermal wounds, without appressoria, started at 12 hai while the mycelial colonization occurred at 72 hai. The infection in immature coffee fruits implies brown eyespot control management anticipation need, even before the first symptoms.Item Sucrose in detoxification of coffee plants whit glyphosate drift(Editora UFLA, 2019-01) Alecrim, Ademilson de Oliveira; Guimarães, Rubens José; Castanheira, Dalyse Toledo; Rezende, Tiago Teruel; Carvalho, Milene Alves de Figueiredo; Voltolini, Giovani BeluttiThe weed control in coffee plants has great importance, as they compete for light, water and nutrients. The chemical control is the most used, emphasizing the glyphosate, however, when applied, drift can occur and consequently cause injuries to coffee. Many farmers use the sucrose application with the objective to reverse the damage caused by the herbicide drift, even without scientific basis to justify such action. The objective of this study was to evaluate the effect of the sucrose application on the detoxification of coffee plants in the implantation phase with glyphosate drift. The experiment was carried out in a greenhouse, using a randomized block design, arranged in a 3 x 3 factorial scheme with 2 additional treatments, using 3 sucrose doses (2, 4 and 8%) with 3 application times (1, 24 and 168 hours after intoxication with 10% of the commercial glyphosate dose) with an additional one in which the plants were not intoxicated and not treated with sucrose and another only with plants intoxicated by glyphosate. After 75 days performing the experiment, growth, physiological and anatomical characteristics were evaluated. The application of sucrose in the reversal of intoxication of growth variables (height, leaf area number of leaves, shoot dry weight and dry weight of the root system) was not efficient. The objective of this study was to evaluate the effect of the sucrose application on the detoxification of coffee plants in the implantation phase with glyphosate drift. For the physiological variables the application of 2% sucrose, one hour after glyphosate intoxication was the most efficient treatment.Item Phialomyces macrosporus reduces Cercospora coffeicola survival on symptomatic coffee leaves(Editora UFLA, 2019-01) Laborde, Marie Caroline Ferreira; Botelho, Deila Magna dos Santos; Rodríguez, Gabriel Alfonso Alvarez; Resende, Mário Lúcio Vilela de; Queiroz, Marisa Vieira de; Batista, Aline Duarte; Cardoso, Patrícia Gomes; Pascholati, Sérgio Florentino; Gusmão, Luis Fernando Pascholati; Martins, Samuel Júlio; Medeiros, Flávio Henrique Vasconcelos deBrown eye spot is among the most important coffee diseases, it is caused by a necrotrophic fungal Cercospora coffeicola. Saprobe fungi have potential in reducing the survival of necrotrophic pathogens and can act through competition of nutrients, mycoparasitism, antibiosis and resistance induction. We have screened saprobe fungi for the ability to reduce C. coffeicola sporulation and viability and determined the possible mechanisms involved in the biocontrol. The selected saprobe fungus, Phialomyces macrosporus, reduced the germination of C. coffeicola conidia by 40%. P. macrosporus produced both volatile and non-volatile compounds that inhibited C. coffeicola growth, sporulation and viability. The production of antimicrobial substances was the main mode of action used by the saprobe fungi. Therefore, P. macrosporus is a promising biological agent for the integrated management of brown eye spot