Coffee Science - v.14, n.4, 2019

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12725

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Effect of intercropping in shading with crotalaria on the initial development of coffee tree
(Editora UFLA, 2019-10) Franco Junior, Kleso Silva; Terra, Ana Beatriz Carvalho; Florentino, Ligiane Aparecida; Carvalho, Julian Silva; Guimarães, Bernardino Cangussu; Silva, Nilton de Oliveira
Coffee cultivation in Brazil is still predominantly in full sun. However, the shading technique has gained prominence to increase the sustainability and profitability of production. Coffee intercropping legumes, besides contributing to shading, act as green manure, improving soil characteristics. Thus, in this study the objective was evaluating the shading intercropping effect on the initial development of coffee trees. The experiment was carried out at Sítio Santa Felicidade, municipality of Campestre - Southern Minas Gerais. Four species of the Crotalaria genus were used and one control treatment without any intermediate species, totaling 5 treatments. The planting was carried out in 4 replicates per treatment, in a randomized block system (DBC), with 16 coffee plants per plot. The 10 central plants were used for evaluation. The variables analyzed were: seedling setting (%), plant height (cm), leaf area index (LAI), number of plagiotropic branch internodes and 50 cm from ground level (cm²), temperature (°C) and soil moisture (%). Data were statistically interpreted by variance analysis and comparisons of averages performed by the Scott-Knott test at 5% probability, using the statistical software SISVAR®. It was observed that, except seedling setting (%) wherein there was no statistical difference among treatments, the other parameters showed positive responses in intercropping with crotalaria when compared to the control, showing the beneficial effect of the use of this legume when intercropped with coffee tree.
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.
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.