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According to the existing problems of no and minimum-till wheat seeding in maize straw covered field in double-cropping system area in North-China Plain, such as residue blockage, high power consumption, a strip rotary-cut-throw anti-blocking implement was developed. Integrated with the principle of anti-blocking implement, the distance L between opener and the anti-blocking implement, sliding-cutting angle τ of the plane-straight blade and rotary speed n were found to be the key parameters which affected anti-blocking performance and power consumption through analysis in terms of residue flow/throwing and mechanical analysis of the implement. Orthogonal experiment was conducted by DEM simulation to optimize the parameters of the implement and analyze the key parameters’ effect on residue blockage and power consumption, the result showed that when the distance was 100mm, cutting edge was 50°, rotate speed was 320r/min, which were optimum parameters set among the trail points, power consumption of the strip rotary-cut-throw anti-blocking implement and the opener was 2.8kW, blocked straw number was 43 in one dm and it could not cause blockage, and then strength check was conducted for this optimum blade by using finite element method and the maximum stress was 1.387×108Pa of which was safe. Field experiment of wheat seeding was conducted on a no-till maize straw covered field, the result showed that strip cut-throw plane-straight blade anti-blocking implement could effectively solve the problem of blockage almost as good as traditional rotary blade under straw coverage of 0.8 kg/m2, 1.6kg/m2 and 2.4kg/m2 at travel speed of 1m/s, 1.25m/s and 1.5m/s, which satisfied the requirements of national standard of no-till fertilization seeder. Compared with strip-rotary implement, power consumption was reduced by 13.83%, soil disturbance was reduced by 37.5 percent points and furrow depth stability was improved by 8.2 percent points. The error of DEM simulation to field experiment in furrow width and depth was 14% and 1.3%, which was tolerable, and the simulation could be referenced to the optimization of strip rotary-cut-throw anti-blocking implement.