Pulverização pneumática no controle de insetos-pragas em áreas reflorestadas com eucalipto

• Autor(a) principal: Mewes, Walter Luiz Castro
• Data de Publicação: 2009
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/676
• topic: Pulverizador pneumático; Eucalipto; Pneumatic pulverization; Eucalyptus; CNPQ::CIENCIAS AGRARIAS::ENGENHARIA AGRICOLA::MAQUINAS E IMPLEMENTOS AGRICOLAS

Wood market is increasing all over the world, and to meet part of this demand, eucalyptus has been planted is large scale in Brazil. Nowadays, this culture occupies more than 4.258.000 ha, generating incomes higher than R$ 8,82 billion in 2008, which makes it very profitable for the country. Its taxonomic proximity to several Brazilian forest species favored the adaptation of many pests to this crop. Among these pests, it is possible to mention the defoliating caterpillars classified as Thyrinteina arnobia, Sarsina violascens and Psorocampa denticulata, which cause severe damage to the eucalyptus production. The attack of these pests occurs in the canopy of the plants and, in many cases, at heights above 20 m, whose control is carried out with the application of Bacillus thurigiensis. The general objective of the present work was to estimate the operating parameters of a pneumatic pulverizer used in the application of phytosanitaries in eucalyptus adult plants higher than 20 m. The specific objectives were: evaluate operating parameters of the pneumatic pulverization; analyze the drip distribution; quantify the liquid retention; and characterize the pulverizer. Hydrosensitive paper tags were used and placed on eucalyptus leaves, with drip collecting surface. The operation parameters evaluated were coverage percentage, drip density, DMV, homogeneity coefficient and SPAN. The drip distribution was evaluated at different heights. In the quantification of the liquid retention, it was used the bright blue dye, and the spectrophometry method was applied. It was carried out the characterization of the pneumatic pulverizer according to the values of the static manometry and dynamic pressure, air flow rate and air speed, consumed power and the reach of the air jet and pulverization drips. The work was carried out using a pneumatic pulverizer manufactured by the Jacto company, activated by a 65,8 kW power motor tractor (85 cv). The parameter essays were carried out on a bridge in the BR 120 road, near Viçosa, MG. The study on the retention of the spray solution and parameters of the drips in eucalyptus plants was performed in CENIBRA production fields, in the city of Belo Oriente, MG. The working parameters of the pulverizer were determined in the Laboratory of Agricultural Mechanization of the Department of Agricultural Engineering of the Universidade Federal de Viçosa. It is concluded that: for the volumetric indexes studied, the best results occurred with the application of 20,2 L 1.000 m-3 of the canopy. The highest spray solution retention occurred in its lower part, and the lowest air flow rate used was efficient. In the evaluation of the drip parameters, the pulverizer was efficient in drip density and in the coverage percentage for the application of insecticides in eucalyptus forests of up to 26 m. As for the technical characterizations, the maximum speed was 52 m s-1, and the increase in the air flow rate of 11.300 m3 h-1 for 13.250 m3 h-1 provided an increment of 28% in the speed and 38% in the power required for activation. Under laboratory conditions, the pulverizer was able to apply products up to 30 m away inside the drip parameters indicated for insecticides.