应用主动作物冠层传感器对马铃薯氮素营养诊断

Active Crop Canopy Sensor-Based Nitrogen Diagnosis for Potato

氮肥的充足供应是马铃薯高产的重要条件,然而氮肥的过量投入会导致资源浪费、环境污染,因此,氮素精准管理势在必行,而实时的氮素营养诊断是实现马铃薯合理氮素养分管理的前提。本研究通过在内蒙古武川县和林西县进行的田间试验,采用主动作物冠层传感器GreenSeeker对马铃薯各生育时期进行实时监测,建立了传感器读数NDVI值与地上部植株氮浓度以及整株吸氮量的关系。研究表明,由于受到土壤背景的影响,苗期NDVI值与马铃薯氮营养指标相关性较差。苗期以后,马铃薯在封垄前NDVI值与植株吸氮量呈显著的指数关系(R2=0.665),封垄后NDVI值与地上部植株氮浓度呈显著的线性关系(R2=0.699),且不受地域以及生育时期的影响。结果表明,主动作物冠层传感器GreenSeeker能够用于马铃薯氮素营养诊断,该结果为进一步建立应用主动作物冠层传感器的氮肥管理提供了理论依据。

In the present study, two potato experiments involving different N rates in 2011 were conducted in Wuchuan County and Linxi County, Inner Mongolia. Normalized difference vegetation index （NDVI） was collected by an active GreenSeeker crop canopy sensor to estimate N status of potato. The results show that the NDVI readings were poorly correlated with N nutrient indicators of potato at vegetative Growth stage due to the influence of soil background. With the advance of growth stages, NDVI values were exponentially related to plant N uptake（Ra =0. 665） before tuber bulking stage and were linearly related to plant N concentration（R2 ~0. 699） when plant fully covered soil. In conclusion, GreenSeeker active crop sensor is a promising tool to estimate N status for potato plants. The findings from this study may be useful for developing N recommendation method based on active crop canopy sensor.