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At this stage, the domestic development of apple tree seedling planting machines is still in its infancy, and few planting machines had been developed for apple trees. Planting apple trees requires a large amount of labor, but the current shortage of labor is a prominent contradiction. The problem of non-mechanized planting of apple tree seedlings urgently needs to be solved. In order to solve the problems in the apple planting process under the current high density dwarfing orchard cultivation mode: low manual planting efficiency, unsatisfactory erection of fruit seedlings with the developed machines, and slightly higher coefficient of variation of plant spacing caused by the slippage of the clamping belt. Under the guidance of agricultural machinery and agronomic integration technology, a two-point clamping apple seedling planting machine was developed by a combination of extensive research, virtual design, prototype manufacturing, and field trials. This machine is based on the existing continuous ditching fixed-distance planting machine previously developed by the same team, and implements structural improvements and performance optimization. Firstly, the fruit seedling clamping device is improved, and the fruit seedlings are clamped at the upper and lower points. On top of the previous generation planting machine, a layer of clamping and conveying device is installed above the lower clamping and conveying device, and the upper and lower layers are perpendicular to each other. The distance is set to be 50cm, which is based on the comprehensive consideration of the height and status of the apple tree seedlings and the comparison of the planting effectiveness at different distances. The upper and lower clamping points work with each other during the transportation of apple tree seedlings to clamp the apple tree seedlings together. The apple tree seedlings will not rotate during operation and maintain a good initial status. It overcomes the problem that it is difficult to guarantee the initial angle of the tall seedlings relative to the ground because of the original one-point clamping, and significantly improves the perpendicularity after planting; Secondly, the transportation method is improved and the coefficient of variation of plant spacing is reduced. Considering that the trunk and bark of apple tree seedlings should not be damaged during the clamping and conveying process of the transplanter, the solution was still sought in the belt category. The initial idea was to add more tension wheels to change the belt slippage. However, the experimental results observed showed that this method makes almost no effect on reducing the belt slip rate. The timing belt can ensure that the apple tree seedlings are protected from damage during the clamping and conveying process, and it has a good transmission effect with little sliding. In order to improve clamping, the conveying mode adopts two synchronous belts to clamp and convey apple seedlings, which has a lower slip rate than the original V-belt clamping and conveying, and significantly reduces the coefficient of variation of the plant spacing; in addition, the power matching is optimized by the corresponding calculation formula. The depth-limiting wheel is installed to improve the stability of the planting depth, and the ditching machine, plant spacing control and other parts follow the first-generation machine plan. According to the planting requirements of different varieties of seedlings, the depth and width of the ditch can be adjusted, and the planting distance can also be adjusted as needed, and the adjustment is simple and convenient. Field tests showed that the qualified rate of apple seedlings planted by the machine is increased from 90.63% to 97.14%, the average planting depth qualified rate is increased from 91.43% to 93.33%, and the average plant spacing coefficient of variation is reduced from 5.03% to 3.74%, and the planting efficiency is increased from 11.89 plants/min to 12.26 plants/min, which was 37 times faster than that of manual planting. Compared with the existing machines, all performances have been improved, laying a solid foundation for the subsequent mechanization of apple's production. [ABSTRACT FROM AUTHOR]