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To overcome the defects like shallow plough layer and low stubble burying rate caused by the high stubble and large amount of straw after rice harvesting when the rapeseed direct seeder works in the riceoil rotation area of the middle and lower reaches of the Yangtze River, a tillage scheme that combined plowing and rotary (P&R) tillage was put forward based on the agronomic requirements of rape plants. A type of buckle device that could lift and then buckle the soil was designed for the rapeseed direct seeder to realize the orderly burying of high stubble and sticky soil. In addition, the rapeseed direct seeder integrated with plowing and rotary tillage was developed. The formation principle of buckled plow surface was expounded. The mathematical models of guiding curve, element angle and generatrix were determined. The mechanical models of the soil ridge and buckling plow were constructed. The buckling process of the plow body surface was clarified. In order to validate the function of buckle device, the test of single plow was carried out under the condition of high stubble. The results showed that the average buckling success rate of the plow was 93.41%, which achieved the desired performance. Field contrast experiments, under the condition that the stubble height were 338mm and 452mm, respectively, were carried out between the seeder with P&R tillage and the seeder with rotary tillage only. Under the two conditions, the plowing depth of the seeder with P&R tillage was increased by 137mm and 110mm, respectively, and the stubble burying rate was increased by 33.94 percentage points and 28.36 percentage points, respectively. The seedbed performance of the seeder with P&R tillage whose operation quality met the requirements of rape sowing was better than that of the seeder with rotary tillage only. The research result provided reference for the design of combined tillage machine and plow surface.