基于TM影像的小麦全蚀病危害信息提取

Detecting Infestation of Take-all Disease in Winter Wheat Using TM Image

为给小麦全蚀病危害监控提供依据,利用ASD Fieldspec HandHeld高光谱仪测量并分析了受小麦全蚀病危害后的光谱特征,并根据TM卫星遥感影像,采用归一化植被指数(Normalized Difference Vegetation Index,ND-VI)和MPA(masking,principal components transformation,and analysis)方法提取和分析了小麦全蚀病危害信息。结果表明,全蚀病发病前麦田的NDVI相近;全蚀病发病期健康麦田NDVI值高于发病麦田;主成分变换后第3主分量在发病前灰度值接近,发病期受害田灰度值大幅上升。利用此技术可简单、快速提取小麦全蚀病危害信息,克服传统手段的局限性,对于实时监控全蚀病危害和改进作物病害监测方法具有重要意义。

Take-all is an important root disease of wheat and has caused considerable decreases in crop yield in China. Although take-all is the most studied disease of any crop, there is little research on detecting the infestation of the disease using remote sensing image. In this article, using ASD Fieldspec Hand-hold Spectroradiometers the reflectance of the winter wheat damaged by take-all disease were measured and analyzed. Based on the difference of the healthy and damaged wheat spectrum, the NDVI（normalized difference vegetation index） and MPA （masking, principal components transformation, and analysis） technique were used to detect the severe infestation of the takeall disease in wheat using TM images. The results showed that the NDVI of the wheat infested by take-all disease was lower than that of healthy wheat; the wheat infested by take-all disease could be differentiated from the third principal component of the masked images. The techniques in this article was simple and effective to detecting and controlling the disease infestation of the take-all disease in wheat.