Periódicos

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

Navegar

Resultados da Pesquisa

Agora exibindo 1 - 3 de 3
  • Imagem de Miniatura
    Item
    Soil chemical attributes in coffee growing with different agronomic techniques
    (Editora UFLA, 2020) Voltolini, Giovani Belutti; Silva, Larissa Cocato da; Alecrim, Ademilson de Oliveira; Castanheira, Dalyse Toledo; Resende, Laís Sousa; Rezende, Tiago Teruel; Guimarães, Rubens José
    The objective was to evaluate the chemical attributes in a coffee growing area, according to different agronomic techniques used and their associations. The experiment was conducted in the field, from January 2016 to October 2018. Coffee was planted in January 2016, with Mundo Novo IAC 379-19 coffee seedlings, with a spacing of 3.6 m between rows and 0.75 m between plants in the planting row. The factors under study were arranged in a 3x2x5 factorial scheme, making a total of 30 treatments. In the plots, three soil managements were randomized (soil cover with polyethylene film, soil cover with brachiaria-grass and conventional management of spontaneous vegetation). In the subplots, two types of fertilizers (conventional and increased-efficiency fertilizer). In the sub-subplots, four soil conditioners (coffee husk, phosphogypsum, water retention polymer, organic compost), and the control without conditioner. Aimed to evaluate soil chemical attributes in coffee growing with different agronomic techniques through the evaluation of: soil pH, phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), aluminum saturation (m) and base saturation (V%). The use of fertilizers combined with the application of organic compost or coffee husk, provide increased soil pH, as well as the use of ecological management of brachiaria-grass. The use of organic compost as a soil conditioner increases phosphorus availability in the soil. Coffee husk, as a soil conditioner, is an efficient potassium source for the coffee crop. The use of organic compost and phosphogypsum increases the calcium and magnesium contents in the soil. The use of organic compost and coffee husk was efficient in increasing the base saturation grown with coffee. The use of organic compost, coffee husk and phosphogypsum reduced aluminum saturation in the soil. Treatments associated with the use of organic compost improve calcium, phosphorus and magnesium levels, increase pH and base saturation, besides decreasing aluminum saturation.
  • Imagem de Miniatura
    Item
    Selectivity of the herbicide chlorimuron ethyl on young coffee plants
    (Editora UFLA, 2019-10) Castanheira, Dalyse Toledo; Voltolini, Giovani Belutti; Alecrim, Ademilson de Oliveira; Rezende, Tiago Teruel; Menicucci Netto, Pedro; Silva, Larissa Cocato da; Guimarães, Rubens José
    The great interference of weeds in coffee plants, due to competition for water, light and nutrients, makes their control essential. Among these control methods, the chemical stands out, due to its high efficiency and low cost. However, as a function of application failures, phytotoxicity is frequent in coffee plants due to herbicide drift. Aiming to search for active ingredients selective to coffee, the objective of this study was to evaluate the selectivity of the active ingredient Chlorimuron ethyl in coffee seedlings, 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.), grown in 11-L pots. The statistical design was in randomized blocks, with four replicates and four herbicide doses. Each plot consisted of three plants. The treatments were: 0%; 50%; 100% and 200% of the recommended commercial dose of the herbicide Chlorimuron ethyl. Evaluations were performed at 120 days after treatment application. Morphological, physiological and anatomical characteristics were evaluated, besides possible phytotoxicity symptoms inherent to herbicide application. The herbicide Chlorimuron ethyl caused phytotoxicity symptoms in coffee seedlings, evidenced from the leaflet dose, through leaf deformation and cracking, with growth losses not exceeding 10%, but without damage to plant physiology and anatomy.
  • Imagem de Miniatura
    Item
    Phytotoxicity and growth of coffee plants as a function of the application of herbicide 2,4-D
    (Editora UFLA, 2019-10) Voltolini, Giovani Belutti; Castanheira, Dalyse Toledo; Silva, Larissa Cocato da; Alecrim, Ademilson de Oliveira; Rezende, Tiago Teruel; Barbosa, João Paulo Rodrigues Alves Delfino; Guimarães, Rubens José
    Weed control in coffee is of great importance for there is a great interference, standing out the competition for water, light and nutrients. Among the control methods, chemical control is highlighted as a function of its efficiency. However, the incorrect application of herbicides may imply the occurrence of drift, resulting in damage to coffee development due to phytotoxicity. In this context, the objective of this study was to evaluate the symptoms and phytotoxicity effects caused by the herbicide 2,4-D drift on the morphological, physiological and anatomical characteristics of coffee seedlings. The experiment was carried out in a greenhouse with ‘Topázio MG1190’ coffee seedlings (Coffea arabica L.), planted in 11-L pots. A randomized block design with four treatments and four replicates was used. The treatments were: 0%; 10%; 25% and 50% of the recommended commercial dose of 2,4-D (2.5 L.ha-1). Each plot consisted of three plants. The evaluations were performed at 74 days after implantation. Morphological, physiological, anatomical and phytotoxicity symptoms were evaluated as a function of the simulated herbicide drift. Coffee seedlings intoxicated by the herbicide 2,4-D presented hyponastic, chlorosis, shriveling and leaf anomalies. In the orthotropic branch, bending was observed in its extension, besides thickening in the collar region; in the plagiotropic branch, cracking was observed. Herbicide drift negatively affects the development of coffee plants. The coffee physiology was affected as a function of herbicide drift, but without damage to the leaf anatomy.