Abstract：In order to estimate pepper plant growth rapidly and accurately, hyperspectral imaging technology combined with chemometrics methods were employed to realize visualization of nitrogen content (NC) distribution. First, pepper leaves were picked up with the leaf number based on different leaf positions, and hyperspectraldata of these leaves were acquired. Then, SPAD and NC value of leaves were measured, respectively. After acquirement of pepper leaves’ spectral information, random-frog (RF) algorithm was chosen to extract characteristic wavelengths. Finally, five characteristic wavelengths were selected respectively, and then thosecharacteristic wavelengths and full spectra were used to establish partial least squares regression (PLSR) models, respectively. As a result, SPAD predicted model had an excellent performance of RC=0.970, RCV=0.965, RP=0.934, meanwhile evaluation parameters of NC predicted model were RC=0.857, RCV=0.806, RP=0.839. Lastly, according to the optimal models, SPAD and NC of each pixel in hyperspectral images of pepper leaves were calculated and their distribution was mapped. In fact, SPAD in plant can reflectthe NC. In this research, the change trend of both was similar, so the conclusions of this research were proved to be corrected. The results revealed that it was feasible to apply hyperspectral imaging technology for mapping SPAD and NC inpepper leaf, which provided a theoretical foundation for monitoring plant growth and distribution of nutrients.
余克强，赵艳茹，李晓丽，丁希斌，庄载椿，何 勇* . 高光谱成像技术的不同叶位尖椒叶片氮素分布可视化研究 [J]. 光谱学与光谱分析, 2015, 35(03): 746-750.
YU Ke-qiang, ZHAO Yan-ru, LI Xiao-li, DING Xi-bin, ZHUANG Zai-chun, HE Yong* . Application of Hyperspectral Imaging for Visualization of Nitrogen Content in Pepper Leaf with Different Positions. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2015, 35(03): 746-750.
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