Design and testify of a sell-manufactured fertilization machine for tobacco variable fertilization based on soil nutrient variation

Using small manual tractor as the carrier, a automatic fertilization machine with necessary parts and softwares was designed and manufactured. Its availability and the yield and economic profit obtained through variable fertilization were testified in tobacco at Leshan Tobacco Hi-tech Park in Zunyi City, Guizhou Province. The soil nutrient variation was studied by sampling soils in grid, and fertilizer application rates of N, P and K prescription were made and automatic implementation of variable fertilization rate was achieved using the small machine. The results show that variable fertilization rate can save 4.6% of fertilizer amount compared to even fertilization, the variation in tobacco plant heights decline 29.6%, improving the uniformity of flue-cured tobacco. The proportion of the first-grade and low-grade commercial flue-cured tobacco was all decreased, and middle-grade was increased by 13.05%. Through variable fertilization, the farmers profit can increase 4310.65 yuan/ha compared with even fertilization. In conclusion, the variable fertilization machine is effective and practical in decreasing labor and fertilizer input, and increases the fertilizer resource efficiency and farmers income.