Near-infrared Analysis of Nitrogen, Potassium, Calcium, and Magnesium in Tobacco Root

The mathematical models for prediction of N、K、Ca、Mg in tobacco root were developed by near-infrared spectrometry and their coefficients of determination were 0.963, 0.936, 0.973, and 0.973, respectively.The four elements in some representative tobacco samples were also predicted with the models, and the predictive relative errors were 5.1%, 9.0%, 7.6%, and 8.1%, respectively.