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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Phytotoxicity and leaf anatomy of young coffee plants subjected to herbicides exclusively and in associations(Editora UFLA, 2020) Rodrigues, Rafael Jorge Almeida; Gonçalves, Adenilson Henrique; Menicucci Netto, Pedro; Carneiro, Arthur Henrique Cruvinel; Castanheira, Dalyse Toledo; Guimarães, Rubens José; Carvalho, Gladyston RodriguesThe lack of work force and the damage that weeds can cause to coffee plants are the causes of the growing demand for selective herbicides to be used in coffee farming. Thus, the objective of this study was to evaluate the phytotoxicity symptoms and leaf anatomical characteristics of young coffee plants submitted to application isolated herbicides and also in associations. An experiment was carried out in a protected environment in randomized blocks: four replicates with coffee seedlings (Coffea arabica L.) cultivar “Topázio MG-1190”, grown in pots with a capacity of 11 liters of substrate. The herbicides applied, in isolation, were: pyrazosulfuron-ethyl (0.015 kg ha-1), saflufenacil (0.049 kg ha-1), imazetaphyr (0.1 kg ha-1), iodosulfuron-methyl (0.0035 kg ha-1), chlorimuron-ethyl (0.015 kg ha-1) and sethoxydim (0.184 kg ha-1). The latter was used in associations with the others. In addition, a control without herbicides was used. Phytotoxicity symptoms were evaluated up to 49 days after application (DAA) and anatomical characteristics at 65 DAA. Saflufenacil exclusively and inassociation with sethoxydim caused visual phytotoxicity symptoms in the leaves and negatively influence in the characteristics of the epidermis thickness of the adaxial face (EAD), thickness of the palisade parenchyma (PAP), thickness of the spongy parenchyma (SPP) and thickness of the mesophyll (MES). The other herbicides, isolated or in associations, didn’t cause phytotoxicity symptoms, but had negative influence in the anatomical parameters of the leaf blade. However they did not interfere with the paradermic parameters and the vascular bundle.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.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 JoséWeed 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.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 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 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%.