通过开展光谱测试试验, 对黄萎病棉叶光谱测试影响因素进行准确性分析, 明确各因素对黄萎病棉叶光谱识别的影响程度, 优化其光谱测试方法。 结果表明: 黄萎病不同严重程度下, 棉叶病症部位反射率形状和大小在所有波段均高于正常部位, 差异显著; 白板做底板时棉叶光谱值在可见光波段略高于黑板, 其他波段显著高于黑板; 棉叶主茎叶影响较小, 旁叶影响较大; 相同或相邻叶位影响较小, 不同叶位影响较大; 正常叶叶位影响较小, 病害叶叶位影响较大; 棉叶背面光谱反射率在可见光波段高于正面, 近红外波段呈先高后平再低的趋势, 短波红外波段呈先高后低的趋势; 不同测试时间, 测试品种的棉叶光谱特征差异较小, 单一条件下对病害识别的影响在可接受范围内; 不同测试试验区的棉叶光谱特征差异很小, 对病害识别基本无影响。 各因素对黄萎病棉叶光谱识别的影响程度不同, 结果可为作物病害光谱识别的研究人员提供参考。

Through carrying out spectral test experiment, the influence factors of spectrum test were analyzed, the influence degree of various factors in spectral recognition was explicated and the method of spectra test was optimized for cotton leaf infected by verticillium wilt. The results indicated that under different severity levels, the shape and value of reflectance of disease symptoms part were Significantly higher than healthy part on cotton leaf, compared with the black board as baseboard, the spectral values of disease leaves were slightly higher in visible light wavebands and significantly higher in others wavebands than healthy leaves on white baseboard. Different position of leaf on cotton plant has different effect degree to the recognition of disease, the effect of stem leaf was more obvious than that of else leaf, the identical leaf position was less influenced by disease than that of others. The effect of healthy leaf was smaller than disease leaf. The reflectance of leaf back was higher than front in visible light waveband, from high to flat, and then low in near infrared waveband, and from high to low to in short infrared waveband. Test time and cotton varieties had less influence on recognizing disease by spectra, and the effect of the same condition was acceptable. Test site had no effect on disease recognition by spectra. The effect of each factor was different for recognizing disease leaf by spectra, and this study will provide reference for the researchers of crop disease diagnosis by spectra.