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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Ecotoxicological Effects of Biochar Obtained from Spent Coffee Grounds(ABM, ABC, ABPol, 2022-11-21) Souza, Lorrana Zélia Martins de; Pinto, Bruna Cristina; Alves, Adriana Barboza; Ribeiro, Amanda Vanessa de Oliveira; Feliciano, Débora Cristina Teodoro; Silva, Luisa Heringer da; Dias, Thiago Tales Moraes; Yılmaz, Murat; Oliveira, Magno André de; Bezerra, Augusto Cesar da Silva; Ferreira, Osania Emerenciano; Lima, Robson Pereira de; Pimenta, Lúcia Pinheiro do Santos; Machado, Alan Rodrigues TeixeiraThe objective of this work is to investigate the conversion of spent coffee grounds (SCG) into biochar (BSC) and the ecotoxicological effects of the product obtained. The SCG and BSC were characterized by characterized by different techniques (TGA/DTG, FTIR, XRD, SEM, EDS, and EDXRF). Proton Nuclear Magnetic Resonance (1H NMR) was used to characterize the aqueous extract of BSC. The inhibitory effect on lettuce (Lactuca sativa) germination was investigated. Besides, antimicrobial activity evaluation trials were conducted with Azospirillum brasilense and Trichoderma spp. The results showed that in the BSC production process, the extractives and lignocellulosic components in the SCG were partly decomposed. Tests conducted with microorganisms did not reveal any toxic effect of BSC. However, high phytotoxicity against lettuce was recorded for rate 100 t/ha of BSC. This effect was associated with the presence of carboxylic acids identified by 1H NMR in the BSC extract aqueous.Item Effectiveness and selectivity of herbicides applied under pre-emergence conditions in weed management for coffee crop(Editora UFLA, 2021) Gonçalves Netto, Acácio; Presoto, Jéssica Cursino; Resende, Laís Sousa; Malardo, Marcelo Rafael; Andrade, Jeisiane de Fátima; Nicolai, Marcelo; Carvalho, Saul Jorge Pinto de; Rodrigues, Matheus Rossi; Marçal, Marcela Borges TomásThe coffee plant is sensitive to weed competition, which negatively affects its growth and development. Thus, the proper and safe use of herbicides is extremely important for weed management to allow the crop to develop its maximum productive potential. The objective of this study was to evaluate the control efficacy of different herbicides under pre-emergence conditions and assess their selectivity for coffee crops. Two experiments were carried out in the field, in randomized block designs, with four replicates and eight treatments, totaling 32 experimental plots. The treatments were: unweeded control; weeded control; sulfentrazone + diuron 1.4 L ha-1; sulfentrazone + diuron 1.7 L ha-1; sulfentrazone + diuron 2.0 L ha-1; sulfentrazone + diuron with indaziflam 1.4 + 0.15 L ha-1; respectively, indaziflam 0.15 L ha-1; and oxyfluorfen + chlorimuron 3.0 L ha-1 + 0.08 kg ha-1, respectively. The treatments were applied prior to the emergence of weeds in a directed spray between the crop rows. Evaluations of weed control in the area, phytotoxicity to the crop, branch length, and internode distance of coffee were conducted at 30, 60, 90, and 120 days after treatment application (DAA). In general, all treatments guaranteed greater than 80% efficacy up to 60 DAA. After this, some treatments suffered reductions in efficacy, and did not guarantee satisfactory con trol up to 120 DAA. For Digitaria nuda, the most effective treatments were those that contained indaziflam alone or in combination with sulfentrazone + diuron, and oxyfluorfen + chlorimuron for 60 DAA. In both experiments and the two species analyzed, the indaziflam treatments guaranteed efficacy percentages above 80%, even at 120 DAA. All treatments were equally selective for the coffee plants under the conditions evaluated.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 JoséThe 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.