Uniform plant stand, herein understood as an outcome of plant spacing and seeding-depth uniformity, requires proper selection of downforce control across varying field conditions, especially when planting at faster ground speeds. Thus, objectives of this study were (1) to assess the effect of ground speed and downforce settings on plant spacing and seeding depth, and (2) evaluate the relationship of planting speed and row-unit vibration. A 12-row planter was used to plant corn on no-till and strip-tilled fields. Treatment factors were downforce setting with two levels: 620 and 980 N, and ground speed with four levels: 7.2, 9.7, 12.1, and 16.1 km h −1 . The planter was programmed to plant corn at 51 mm seeding depth at a seeding rate of 84,000 seeds ha −1 , equivalent to a theoretical plant spacing of 178 mm. No significant downforce effect was observed at either field on plant spacing, although the low downforce setting resulted in lower plant spacing variability. Higher variability in spacing was observed with increasing ground speed. Target seeding depth on the no-till field was achieved with high downforce and slower ground speed, while deeper than the target seeding depth on the strip-tilled field was observed with a high downforce setting. Finally, both downforce settings revealed increasing row-unit acceleration as ground speed increased.

中文翻译：

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地速和播种机下压力对玉米种子间距和深度的影响

Uniform plant stand, herein understood as an outcome of plant spacing and seeding-depth uniformity, requires proper selection of downforce control across varying field conditions, especially when planting at faster ground speeds. 因此，本研究的目标是 (1) 评估地速和下压力设置对种植间距和播种深度的影响，以及 (2) 评估种植速度和行单元振动的关系。使用 12 行播种机在免耕和条耕田上种植玉米。处理因素是两个级别的下压力设置：620 和 980 N，以及四个级别的地速：7.2、9.7、12.1 和 16.1 km h -1 。播种机被编程为以 51 毫米播种深度以 84,000 粒种子 ha -1 的播种率种植玉米，相当于 178 毫米的理论株距。尽管较低的下压力设置导致较低的植物间距变异性，但在任一地块均未观察到显着的下压力效应。随着地速的增加，观察到间距的变化更大。免耕田的目标播种深度是通过高下压力和较慢的地面速度实现的，而在高下压力设置下观察到比条耕田的目标播种深度更深。最后，两种下压力设置都显示出随着地速增加而增加的行单位加速度。而在高下压力设置下观察到比条耕田上的目标播种深度更深。最后，两种下压力设置都显示出随着地速增加而增加的行单位加速度。而在高下压力设置下观察到比条耕田上的目标播种深度更深。最后，两种下压力设置都显示出随着地速增加而增加的行单位加速度。