玉米植株抗倒性测量装置设计与试验

针对现有玉米植株抗倒性测量装置的人工施力速度不稳定且未能垂直于植株进行测量，致使测量结果误差较大的问题，设计一种以电机驱动的玉米植株抗倒性测量装置。该装置可快速测量玉米茎秆从直立到不同倒伏角度时所能承受的最大力矩。通过对玉米倒伏时的受力进行分析，建立植株力学模型，提出评价玉米抗倒性的指标。进行装置检测角度精确性试验，结果表明：该装置检测角度与实际角度的偏差为1°，满足检测要求。进行装置加载速度稳定性试验，结果表明：所设计装置的测量角度随时间变化平稳，验证了装置加载速度的稳定性。分别以最大抗推力矩和最大抗拉力为指标，对不同玉米品种和种植密度进行了推、拉倒伏田间试验。结果表明：在密度75000株/hm2时，最大抗推力矩和最大抗拉力与倒伏率的相关系数分别为-0.971、-0.873。在密度105000株/hm2时，最大抗推力矩、最大抗拉力与倒伏率相关系数分别为-0.991、-0.927。结果表明，以最大抗推力矩作为评价抗倒伏能力指标优于最大抗拉力。在田间试验基础上，以最大抗推力矩为试验指标进一步开展装置可靠性验证试验，试验结果与现有研究结论一致。

Design and Test of Measuring Device for Anti-collapse Characteristic of Maize Plant

Aiming at the problem that the existing measuring device for anti-collapse characteristic of corn plants is unstable and not perpendicular to the plant, which results in large error of measuring results, a measuring device for anti-collapse characteristic of corn plants driven by motor was designed. The device can quickly measure the maximum moment that the corn stalk can withstand from erect to different angles of lodging. Based on the analysis of the stress on lodging of maize, the plant mechanical model was established and the index of anti-collapse characteristic was put forward. The test results showed that the deviation between the detection angle of the device and the actual angle was 1°, which met the detection requirements. The stability test of the loading speed of the device was carried out, and the results showed that the measuring angle of the designed device changed smoothly with time, which verified the stability of the loading speed of the device. Taking the maximum pushing moment and maximum pulling force as indexes, the field experiments on pushing and pulling lodging of different maize varieties and planting densities were carried out. The results showed that the correlation coefficients of maximum pushing moment and maximum tensile strength were -0.971 and -0.873, respectively at the density of 75000 plants/hm2. At the density of 105000 plants/hm2, the correlation coefficients of maximum pushing moment and maximum tensile strength were -0.991 and -0.927, respectively. The results showed that the maximum pushing moment was better than the maximum pulling force. Based on the field test, the reliability verification test of the device was further carried out with the maximum push-moment as the test index, and the test results were consistent with the existing research conclusions.