Navegando por Autor "Lemes, Ernane Miranda"

Agora exibindo 1 - 2 de 2

Canopy volume and application rate interaction on spray deposition for different phenological stages of coffee crop
(Editora UFLA, 2020) Alves, Thales Cassemiro; Cunha, João Paulo Arantes Rodrigues da; Alves, Guilherme Sousa; Silva, Sérgio Macedo; Lemes, Ernane Miranda
Coffee plants (Coffea arabica L.) present dense foliage that obstruct the entering of pesticides inside the plant canopy uniformly. Adjust the application rate concerning the plant canopy volume can be a way to make the pesticide applications more efficient. The objective of this study was to evaluate the deposition of spray solution on coffee leaves with different volumes of plant canopy and different application rates; additionally, to determine the specific volume indexes for different coffee phenological stages. The studies of coffee leaf deposition were performed on commercial fields of C. arabica – Topázio MG 1190 and Catuaí Vermelho IAC 99 cultivars, in different months. Three volumes of vegetation ranging from 8.572 to 16.200 m3 ha-1 - obtained from the calculation of tree-row volume (TRV) performed in 20 plants - and five application rates (200, 300, 400, 600 and 800 L ha-1) and in each phenological stage (maturation, post-harvest, grain filling) were evaluated in a randomized block design with five replications. A bright blue marker was added to the spray solution to be detected by spectrophotometry in order to study the spray deposition and losses to the soil. After the treatment applications, ten coffee leaves corresponding to the 1st pair of leaf from an orthotropic branch of each third of the coffee plant (upper, middle, lower) were randomly collected. Petri dishes were used to evaluate the losses to the soil. The TRV and leaf density should be considered together in the definition of the application rate for coffee protection. It is also possible to reduce the application rate to values close to 200 L ha-1. The volume indexes for each coffee phenological stage were defined for proper canopy wetting and low losses to the soil.
Soil attributes in conventional tillage of Coffea arabica L.: a case study
(Editora UFLA, 2018-04) Mota, Raquel Pinheiro da; Almeida, Risely Ferraz de; Lemes, Ernane Miranda; Buiatti, Camilla; Alvarenga, Lettícia; Magela, Mara Lúcia Martins; Camargo, Reginaldo de
Coffee production presents great economic and social importance. To increases coffee production and decreases the environmental impacts of its activity, it is necessary to know the soil attributes and their impacts on plant development. Therefore, due to the importance of the soil physical and chemical attributes, as well as the significance of coffee to Brazil, the objective of this study was to evaluate the physical and chemical attributes of an Oxisol planted with coffee conducted under conventional tillage system. For the purposes of analysis and interpretation of the data, the experiment was performed and interpreted in a completely randomized design, with the factorial 3 x 2, referring to three locations in the area of the coffee plantation (planting line, canopy projection, between planting lines) and two soil layers (0 - 0.2 m and 0.2 - 0.4 m), with four replications. It is concluded that no distinctions for soil porosity and total porosity was observed among soil locations, and that ‘planting line’ position showed superior concentrations of total organic carbon and mean geometric diameter of the soil aggregates.