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Ditching fertilization is one of the important links of fruit planting, which is done artificially with large labor intensity but low efficiency, failing to satisfy the requirement of high quality fertilization for modern orchard. The disc-type ditcher is a kind of continuous earthmoving machinery followed by the chain ditcher, which is characterized by high efficiency and convenient operation, and widely used in the farmland water construction and orchard ditching fertilization, etc. But the existing ditching blade has the problems of large power consumption and poor stability of ditch depth. A sine-exponential curve ditching blade was designed through analyzing the advantages and disadvantages of existing blade, using the rotary tillage theory and experimental analysis. Through the analysis of tractor forward speed, rotating speed of the cutter, as well as the influence of their interaction on power consumption and ditch depth stability, the optimal working parameters of the sine-exponential curve ditching blade were as following: tractor forward speed was 1 m/s, rotating speed of cutter was 200r/min. The optimal structure parameters of the sine-exponential curve ditching blade were determined through the three-factor four-level orthogonal test with bending angle and bending radius in B and bending angle in C of the sineexponential curve ditching blade as impact factors, and power consumption and groove depth stability as response value: bending angle in B was 95°, bending angle in C was 140°, and bending radius was 9mm. Through comparing the sine-exponential curve ditching blade with existing blade, it was showed that under the same working parameters and ditching depth, the power consumption of the sine-exponential curve ditching blade was decreased by 3.29kW and ditching depth stability was increased by 8.83 percentage points compared with the existing blade. Index of the technical specifications for the sine-exponential curve type ditching blade is higher than the national standard. The research results provided a theoretical basis for the sine-exponential curve type furrowing blade optimization design. 