棉花黄萎病冠层高光谱遥感监测技术研究

通过小区试验地病圃田和大田实验,不同时期对不同品种棉花黄萎病冠层光谱分别进行测定,定性和定量地分析了其反射光谱特征.结果表明:不同时期、不同品种棉花黄萎病冠层光谱与正常冠层之间有着显著的差异,冠层光谱均随严重度(SL)的增加表现出有规律的变化,可见光(620～700 nm)波段,光谱反射率随SL增加呈现上升趋势,近红外(700～1 300 nm)波段则表现出相反的趋势,在近红外(760～1 300 nm)尤为明显.黄萎病冠层光谱与SL相关后发现,806 nm附近SL(Y)与冠层光谱反射率(X)的相关性达到了极显著水平,二者之间的回归模型为:Y=-11.64 X+7.072 2(R2=0.675).研究为今后航空、航天遥感大面积监测棉花黄萎病提供了理论依据,为棉花其他病害遥感监测提供了借鉴和参考.

Studies on Monitoring Canopy Spectrum of Cotton Verticillium wilt by Remote Sensing Technique

With the rapid development of information technology,remote sensing,as a fast monitoring means,has been used in monitoring crop diseases and pests in recent years.Some domestic and overseas scholars have had some bold experiments and made a great deal of achievements.Spectrum of variety cotton canopy of Verticillium wilt were measured at different periods in tentative disease field and characteristics of reflectance spectrum were analyzed qualitatively and quantitively.The results showed that there was significant difference between canopy spectrum of Verticillium wilt of cotton and regulary cotton canopy based on different periods and different varieties.Spectral reflectance increased significantly at visible light region(620～700 nm) wave-infrared region with the increase of the SL,it inverted at near-infrared region(700～1 300 nm)and specially significant at 780～1 300 nm.After analyzing relation between spectral of cotton canopy of Verticillium wilt and SL,distinct differences in reflectance at 806 nm among different SL were found also a regression model among SL and reflectance of cotton canopy of Verticillium wilt in the field: Y=-11.64X + 7.072 2(R2=0.675 for reflectance,Y for SL)were built.It provided theoretical foundation for further monitoring Verticillium wilt of cotton at large scale using airborne and airspace remote sensing data and reference for other cotton illness.