DEPENDÊNCIA ESPACIAL DA DEPOSIÇÃO DE CALDA PROMOVIDA POR UMA APLICAÇÃO AÉREA NA CULTURA DA SOJA

Abstract

The aerial application of pesticides is a valuable tool in agriculture, when based on well-defined technical criterion. This paper aimed to evaluate the spatial dependence of the drops spectrum and its deposition by an aerial application over the soybean crop (Glycine max). An experimental agricultural aircraft was used, model Acrobat, from England Company, equipped with eight rotary atomizers, model Micronair AU 5000, applying a spray volume of 20 L ha-1. To obtain the droplet spectrum were used hidro sensitive targets consisting of paper, distributed in the middle third and higher plants. Spectrum analysis of the drops was made using the computer program "CIR" version 1.5 in 2002. To determine the amount deposited on the leaves of the upper, middle, and bottom of the soybean plants, we used the bright blue food coloring added to the spray solution. These leaves were washed and the amount determined by spectrophotometry. The analysis of spatial dependence was evaluated using the GS + version 7 program. The results show no spatial dependence for the attributes. There was a low percentage of coverage in the upper and middle third of the plants. The geostatistical analysis can be used to characterize the spatial attributes of application coverage, but should be used a sampling grid of smaller size.