Design of liquid fertilizer applicator based on Variable Rate Application (VRA) for Soybean

The process of fertilization is one of the phase that is very important in improving the quality and quantity crops. The needs of plants nutrient on one stretch of the fact that not entirely uniform. In addition the use of chemical fertilizer continously with the doses increasing each year can upset the balance lands nutrient therefore it is necessary variable-rate liquid fertilizer applicator to set a dose of fertilizer required by the plant. This study attempts to design and test the performance of variable-rate liquid fertilizer applicator and soil nutrrient test. The applicator can be used to 4 line the soybean plant with distance cropping 40x20 cm. This applicator can control travel speed and dosage of fertilizers that were out of 4 Nozzle. Evaluation and its performance tested in the laboratorium. Discharge that was issued on PWM motor sprayer variations 40 to 100 produce discharge markedly dissimilar variations on each of the PWM sprayer. In application uniformity evaluations use the coefficient of variation (CV). The coefficient of variation of the discharge range 2.71-12.37 and there is a diversity of N, P and K soil contents in each land tested although the changes are not too different.