Daniel Mariano Leite

Deslizamento de rodados de tratores de pneus em diferentes operações agrícolas

Wheel sliding of tractors in different agricultural operations In tractors, the wheel sliding is caused by several factors, including the tractive effort required to move a certain implement and type of surface that is in contact with the tire treads. This study aimed at evaluating the wheel sliding of a tractor in different corn tillage systems in Bambui, MG, Brazil. The experiment was conducted in the field in the second crop of autumn 2011 at the Minas Gerais Federal Institute – campus Bambui (Experimental Station) in an Oxisol Ustox. The experiment was arranged in split-plots, with the operations in the plots, the gears in the splitplots and rotations in the split-splitplots, in a randomized block design with three replications, totaling eighty-one experimental units. The factors and levels studied were: (CT) conventional tillage (MT), minimum tillage (NT) and no tillage. Each treatment used three run speeds (A2, A3 and B1) in three motor rotations (1600, 1900 and 2200 rpm). The results showed that in the conventional tillage, the highest wheel sliding occurs in the sowing operation; in the minimum tillage, the highest wheel sliding occurs in the operation of scarification; and in no tillage system in the sowing operation.

Quantitative losses in mechanized harvesting corn crop in small footprint and conventional

The objective of this study was to evaluate the quantitative losses occurred in the mechanical harvesting of the corn grown in conventional and reduced gaps. The experimental design was randomized blocks with three replications and treatments distributed in a factorial (2 x 3 x 3), and two spacings (0.45 m and 0.90 m), three speeds of the combine (1.8 km. h-1 3.5 km. h-1 and 4.1 km. h-1 ) and three openings of the concave (25 mm, 30 mm and 35 mm). For treatments where the spacing was 0.45 m, the harvester worked with a power of two lines dividing line between the platform crop while in treatments where the spacing was 0.90 m, the harvester worked with a power dividing line between a line of platform. The plant population was the same for the two spacings used in the experiment. The natural losses were higher in the conventional spacing, but the header losses of harvest had the lowest use this space 1

Use of digital images for evaluating soil compaction in the culture of beans

A produtividade do feijoeiro no Brasil e considera baixa entorno de 820 kg ha-1, podendo atingir valores acima de 3.000 kg ha-1, varios fatores ambientais podem limitar o bom desempenho da cultura, principalmente os relacionados ao solo. Sendo assim objetivou-se com a realizacao deste trabalho avaliar a compactacao do solo na cultura do feijoeiro em diferentes sistemas de manejo do solo, por meio de imagens digitais. Este trabalho foi realizado na Universidade Federal de Vicosa, utilizou-se o delineamento em blocos ao acaso com seis repeticoes, sendo quatros tratamentos avaliados (plantio direto, preparo convencional, cultivo minimo utilizando grade niveladora-destorroadora e cultivo minimo utilizando escarificador). Foram avaliados a resposta espectral utilizando indices de vegetacao (NDVI, RS, GNDVI, VARI, WDRVI e SAVI), calculados a partir dos valores dos numeros digitais das imagens e dos valores estimados da reflectância. Para aquisicao das imagens foi utilizado uma plataforma contendo duas câmeras digitais, uma sensivel na regiao do visivel (RGB) e a outra sensivel na regiao do infravermelho proximo, esta plataforma foi acoplada a um balao inflado com gas helio. Os indices de vegetacao obtidos a partir dos valores dos numeros digitais das imagens so foram capazes de diferirem os tratamentos aos 70 dias apos o plantio. Os indices obtidos pelos valores estimados da reflectância diferiram os tratamentos aos 34 e 70 dias apos o plantio.