Abstract: In an attempt to resolve the prevalent issues encountered during the operation of the plowing, leveling, and seeding integrated machine, such as the suboptimal soil backfilling and soil fragmentation effects, along with the relatively high tillage resistance, a straight - blade rotary tillage blade featuring bionic structural characteristics has been meticulously designed, drawing inspiration from the contour curve of the shark's dorsal fin. The process of designing this bionic blade is not only a creative endeavor but also a scientific exploration aiming to leverage the unique biological features of sharks to enhance the performance of agricultural machinery.When it comes to analyzing the contour of the dorsal fin, the Gaussian equation is employed for fitting. Through a series of rigorous calculations and analyses, it is found that the R² value is extremely close to 1 and the SSE value approaches 0. This outcome serves as strong evidence to verify the superiority of the function equation selection and fitting, as well as the high accuracy of data prediction. Such a precise fitting process is crucial as it allows for a more accurate representation of the dorsal fin's contour, which is the foundation for the design of the bionic rotary tillage blade.Utilizing the discrete element simulation software, a comprehensive quadratic orthogonal rotation combination simulation experiment is conducted. In this experiment, the rotary speed of the blade roller n, the forward speed of the machine v, and the tillage depth h are selected as the influencing factors, while the backfilling rate P, the soil fragmentation rate I, and the tillage resistance F are chosen as the evaluation indicators. By carefully manipulating these factors and observing the corresponding changes in the indicators, a detailed understanding of the performance of the bionic rotary tillage blade under different operating conditions can be obtained.The simulation results reveal that when the rotary speed of the blade roller reaches 241 r/min, the forward speed of the machine is set at 0.65 m/s, and the tillage depth is maintained at 120 mm, the contact model between the bionic rotary tillage blade and soil particles achieves an optimal solution. This optimal state indicates that under these specific operating parameters, the bionic blade can operate most efficiently, achieving a good balance between soil backfilling, fragmentation, and tillage resistance.The average backfilling rates of bionic knives, straight-edge knives, curved knives and chisel-shaped knives were 84.34%, 75.32%, 61.73% and 68.46% respectively. The average soil fragmentation rates were 79.7%, 69.26%, 74.56% and 72.24% respectively; The average tillage resistances were 87.2N, 103.37N, 122.61N and 115.39N respectively.To further validate the performance of the bionic rotary tillage blade, which an indoor soil trough test is carried out. The test results clearly show that the backfilling rate of the bionic rotary tillage blade is 84.34%, the soil fragmentation rate is 79.7%, and the average tillage resistance is 87.25 N. When compared with the straight - blade blade, the curved blade, and the chisel - shaped blade, the bionic blade demonstrates remarkable advantages. Specifically, its backfilling rate increases by 11.98%, 36.62%, and 23.2% respectively; the soil fragmentation rate goes up by 15.07%, 6.89%, and 10.32% respectively; and the tillage resistance decreases by 15.59%, 28.83%, and 24.38% respectively. Additionally, the relative errors between each index and the simulation results are 3.7%, 3.2%, and 4.5% respectively, indicating a high degree of consistency between the simulation and the actual test.In conclusion, the results of both the simulation experiment and the indoor soil trough test clearly indicate that the bionic rotary tillage blade can effectively reduce the tillage resistance while significantly improving the backfilling rate and soil fragmentation rate of the rotary tillage operation. This fully verifies the correctness and practicality of the design. The research results are of great significance as they can provide a valuable blueprint for the research, development, and optimization of the strip rotary tillage device, promoting the progress of agricultural machinery technology.