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Spray fertilizer needle is the executive component of pricking hole mechanism, which is working on the soil directly, so its construction feature will affect the fertilization quality. In order to improve the operation quality, a new type spray fertilizer needle with double oblique hole was designed and its dynamics characters were studied. On the dynamics testing system bench, taking forward speed of soil tank vehicle and rotation speed of planet carrier as experimental factors, and the reaction of soil particles to spray fertilizer needle as indicator, the reaction force of soil particles to spray fertilizer needle during pricking hole was determined. Result shows that, the tensile stress of needle was decreased with the increasing forward speed and rotation speed, which was in the range of 19.944~25.936N. Bending force was increased with the increasing forward speed and rotation speed, which was in the range of 8.62~75.32N. The rotation speed has a significant effect on the reaction of spray fertilizer needle. According to the test results, the rotation speed of planet carrier with the range of 100~120r/min could improve the work efficiency and ensure normal work of pricking hole mechanism.