Navegando por Autor "Costa, Carlos Emanuel de Melo"

Agora exibindo 1 - 2 de 2

Growth and physiological response of coffee seedlings ruela, treated with fungicides
(Editora UFLA, 2019-04) Ruela, Viviane Maria; Silva, Adriano Bortolotti da; Veiga, André Delly; Souza, Thiago Corrêa de; Marques, Daniele Maria; Costa, Carlos Emanuel de Melo; Rezende, Tiago Teruel
Research has shown that, in addition to the fungicidal action already known, strobilurins have positive physiological effects on the yield of some crops. Boscalid has also shown positive effects on plants, applied together or associated with strobilurin. The objective in this study was to evaluate the effect of fungicide application on growth and physiological behavior of coffee seedlings. The experimental design was in randomized blocks, with five replicates. There were five treatments: T1-Control, T2-Boscalid, T3-Pyraclostrobin, T4- Boscalid+ Pyraclostrobin and T5- Azoxystrobin applied in coffee seedlings. The application was at the “orelha de onça” stage (two round-shaped leaves), repeated every 15 days, counting 5 applications in total. Were evaluated shoot length, root length, stem diameter, shoot and root fresh matter, shoot and root dry matter, leaf photosynthesis, stomatal conductance, transpiration, intercellular CO2 concentration, water use efficiency and carboxylation efficiency. The application of fungicides promotes greater vegetative growth of coffee seedlings due to increased CO2 assimilation rate, reduced transpiration rates and increased water use efficiency, associated to the increased levels of auxin and cytokinins in leaves.
Occupational noise level in mechanized and semimecanized harvest of coffee fruits
(Editora UFLA, 2018-10) Silva, José Antonio Ramos da; Oliveira Júnior, Geraldo Gomes de; Costa, Carlos Emanuel de Melo; Silva, Adriano Bortolotti da; Gabriel, Camila Pires Cremasco; Putti, Fernando Ferrari
Coffee cultivation has undergone significant changes, especially with regard to the mechanization process of the various existing operations that were previously carried out manually by the workers. It is observed that the intensification of mechanized activities can expose workers to noise levels capable of compromising their hearing health. In this sense, the objective in the present study was to determine the level of occupational noise in the activities of mechanized and semi- mechanized harvesting of coffee fruits and compare them with the limits of tolerance of the current legislation. The occupational noise level was determined considering the exposure of homogeneous groups, using an integrative meter for personal use, noise dosimeter, electromechanically calibrated and with field calibration. The results demonstrate that the noise levels found are above the limits allowed for an 8-hour working day. The highest observed level was 100.7 dB (A) in the sweeping operation with the blower equipment and the lowest level 89.0 dB (A) in the auxiliary activity of the selected collection equipment Vicon H3000. Harvesting activity with a portable mechanical stripper equipment showed a noise level 4.2% higher compared to harvesting with automotive harvester equipment.