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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Resultados da Pesquisa
Item Initial performance of coffee trees with different fertilizationand irrigation management(Universidade Federal de Lavras, 2022-06-09) Silva Júnior, José Geraldo da; Pin, Iago Parmanhani; Ferreira, Daniel Soares; Castanheira, Dalyse ToledoCoffee is one of the main agricultural commodities in the world. However, due to its sensitivity to water stress and changes in the availability of finite sources of nutrients and the constant search for a more sustainable agriculture, it is necessary to modulate the responses of plants to soil water and the real nutritional demand of the coffee tree. Thus, the objective of this work was to analyze the initial performance of arabica coffee grown with or without water restriction and with five different soil fertilization managements, in order to propose more techniques to optimize coffee production. The exper-iment was carried out in a greenhouse, in the experimental area of the Federal University of Viçosa, in the city of Viçosa-MG. The experimental design was completely randomized in a 2x5 factorial scheme, with two irrigation depths (40% and 80% of the available water in the soil) and five fertilization managements (conventional 100% of the recommended dose, controlled release of 80 and 100% of N and recommended K and organomineral 80 and 100% N and K of the recommended dose). In view of the observed results, it can be observed that water restriction in the initial period of coffee develop-ment provided a reduction in the variables of root and shoot growth of the plants, regardless of the soil fertilization management used. In environments with greater water restriction, no significant difference was observed between the studied fertilizers and in an environment without water restriction, the controlled release fertilizer 80% presented the highest global growth averages. Water management provided a greater effect on coffee nutrient dynamics than duly studied fertilization management.Item Water retainer polymer in coffee plants deployment under different levels of irrigation(Editora UFLA, 2021) Resende, Thales Barcelos; Souza, Victor Hugo Silva; Castanheira, Dalyse Toledo; Carvalho, Milene Alves de Figueiredo; Guimarães, Rubens JoséThe use of water-retaining polymers may be a feasible alternative in regions with low water availability, as they has enhance the performance of coffee plants with more favorable anatomical characteristics to make physiological processes more efficient. However, the advantages of such use have been scarcely reported. Here, we studied the feasibility of using a water-retaining polymer to optimize irrigation water use during the establishment of a coffee plantation. A randomized block design was used in a factorial scheme (4 × 2) with three replications for a total of 24 experimental plots, each consisting of four pots, with one plant per unit. The experiment was installed in a greenhouse at the Coffee Science Department of the Universidade Federal de Lavras, Minas Gerais, Brazil, with four levels of irrigation (25%, 50%, 75%, and 100% of soil water at field capacity), with or without addition of the water-retaining polymer. Growth variables evaluated included: plant height, stem diameter, number of leaves, shoot and root dry weights, root volume and area. Additionally, gas exchange, leaf water potential, and leaf anatomy were analyzed. The use of water-retaining polymer during establishment of the coffee plantation ensured sufficient water supply, thus guaranteeing plant anatomical and physiological functionality and, consequently, a healthy, vigorous growth.Item Selectivity of fluazifop-p-butyl in young coffee plants(Editora UFLA, 2019-07) Voltolini, Giovani Belutti; Castanheira, Dalyse Toledo; Menicucci Netto, Pedro; Alecrim, Ademilson de Oliveira; Rezende, Tiago Teruel; Guimarães, Rubens José; Gonçalves, Adenilson HenriqueWeed control is fundamental in coffee cultivation due to their big interference, competing with the crop for water, light and nutrients. Among the control methods used, chemical control is highlighted, as a function of its high efficiency and low cost. However, due to application failures, herbicide drift phytotoxicity is common. Aiming at the search for selective active ingredients in coffee plants, the objective in this study was to evaluate the selectivity of the active ingredient Fluazifop- p-butyl on the young coffee plants, and its effects on plant morphology, anatomy and physiology. The experiment was carried out in a greenhouse, with ‘Topázio MG 1190’ coffee plants (Coffea arabica L.), cultivated in pots with a capacity of 11 L substrate. The statistical design was randomized block design (RBD), with four replications and four doses of the herbicide, making up 16 experimental plots. Each plot consisted of three plants. The treatments were: 0%; 50%; 100% and 200% of the recommended commercial dose of the herbicide Fluazifop-p-butyl. The evaluations were performed at 120 days after application of the treatments. Morphological, physiological and anatomical characteristics were evaluated. Regardless of the evaluated characteristic, there was no difference between the doses of the herbicide. There were no visual phytotoxicity symptoms in the young coffee plants that received the herbicide Fluazifop-p-butyl. The growth of the coffee plants and the physiological and anatomical characteristics were not altered due to the application of the herbicide Fluazifop-p-butyl.Item Agronomic techniques for mitigating the effects of water restriction on coffee crops(Editora UFLA, 2019-01) Castanheira, Dalyse Toledo; Barcelos, Thales Resende; Guimarães, Rubens José; Carvalho, Milene Alves de Figueiredo; Rezende, Tiago Teruel; Bastos, Isadora dos Santos; Cruvinel, Arthur HenriqueWater restriction significantly affects coffee (Coffea arabica L.) production. The study of a few agronomic techniques that optimizes water use can generate technologies for mitigating the effects of climatic variations on coffee crops. The aim in this study was to indicate agronomic techniques that mitigate the effects of water restriction on coffee crops. For this end, we analyzed the morphophysiological changes in coffee plants cultivated in a greenhouse with different types of fertilizers and soil conditioners and under two levels of irrigation. The evaluations were performed 130 days after planting, assessing the morphological and physiological characteristics of the plants. We also quantified soil moisture in the different treatments. The water restriction expressively hindered plant growth. The use of controlled release fertilizers and soil conditioners, especially coffee husk, is indicated for mitigating water restriction in coffee crops.Item Quantitative analysis of growth in coffee plants cultivated with a water-retaining polymer in an irrigated system(Universidade Federal do Ceará, 2016-01) Souza, Antonio Jackson de Jesus; Guimarães, Rubens José; Colombo, Alberto; Sant’Ana, José Antonio do Vale; Castanheira, Dalyse ToledoThis study aimed to evaluate the use of hydro polymer retainer in the quantitative growth of coffee plants at different levels of irrigation and soil types. The experiment was conducted in pots with seedlings bag in the greenhouse of the Setor de Cafeicultura, Universidade Federal de Lavras. The experimental design was in randomized blocks in factorial (2x4x2): absence or presence of hydro polymer retainer, four levels of irrigation (25%, 50%, 75% and 100%), two soil types (sandy soil and medium texture). At 150 days evaluated the stem diameter, plant height, leaf area, number of leaves, dry weight of shoots, plant dry mass, root dry weight, root dry weight ratio of shoot, leaf area ratio, absolute growth rate, relative growth rate, net assimilation rate and leaf area index. It was concluded that the polymer hydro retainer hydrated favored the growth of coffee plants and irrigation promoted greater growth of coffee in medium textured soil compared to soils with sandy texture.Item Sintomas de fitotoxicidade e crescimento de mudas de silva, café submetidas aos herbicidas inibidores da protox(Editora UFLA, 2017-07) Silva, Lucas Guedes; Castanheira, Dalyse Toledo; Voltolini, Giovani Belutti; Souza, Itamar Ferreira de; Gonçalves, Adenilson Henrique; Guimarães, Rubens JoséObjetivou-se avaliar a influência dos herbicidas flumioxazin,oxyfluorfen e carfentrazone-ethyl no crescimento inicial de mudas de cafeeiro, sob condições de campo, identificando os sintomas de fitotoxicidade causados nas plantas. Os experimentos foram realizados em delineamento de blocos casualizados, com quatro repetições, e seis doses de herbicida (0%, 10%, 40%, 70%, 100% e 200% da dose recomendada). As aplicações foram feitas diretamente sobre as plantas por meio de um pulverizador costal pressurizado por CO 2 , regulado a 45 kgf/cm2. As mudas permaneceram no campo por 45 dias após as pulverizações, sendo realizada a identificação e observação dos sintomas de fitotoxicidade. A observação dos sintomas de fitotoxicidade foi feita a cada dois dias, por meio da captura de imagens e comparação das plantas que receberam os herbicidas com a testemunha. Ao final do experimento foram avaliados o número de folhas, o diâmetro de caule e a massa seca da parte aérea das plantas. Nos herbicidas oxyfluorfen, carfentrazone – ethyl e flumioxazim, a partir da dose de 10%, o principal sintoma de fitotoxicidade observado foi a formação de manchas necróticas irregulares no limbo foliar, principalmente nas regiões apicais. Os herbicidas oxyfluorfen e carfentrazone-ethyl, em todas as doses estudadas, apesar de causarem fitotoxicidade e injúrias leves nas mudas de cafeeiro, não afetaram o seu crescimento. O herbicida flumioxazin apresentou maior fitotoxicidade nas mudas, reduzindo significativamente seu crescimento em relação à testemunha, a partir da dose de 10%.