Abstract: This paper aimed to optimize the efficiency and accuracy of existing identification methods for flue-cured tobacco leaf varieties and further enhance the usability of tobacco leaves in the cigarette industry.Based on the CIELAB color space theory, chroma values of three varieties of flue-cured tobacco leaves from the Kunming production area were measured using a chroma meter, and a method for rapid and accurate identification of tobacco leaf varieties was established. The results showed that both chroma values and appearance characteristics could be used to identify different varieties of flue-cured tobacco leaves, but the chroma values measured by the chroma meter were more accurate and reliable, and the chroma values could better reflect the appearance characteristics of tobacco leaves.Although there was a small amount of overlap between different samples, the overall clustering effect was good, indicating that there were differences in chroma values between different varieties from the same position, which could effectively characterize the features of each variety. A Fisher discriminant model was established using indicators such as lightness (L*), red-green chroma value (a*), yellow-blue chroma value (b*), saturation (C), and color difference (ΔE). The cross-validation results of the model showed that the recognition rate of the training set was 83.3%, and the cross-validation recognition rate was 81.1%. The two results were close and both at a high level, indicating that the model could effectively identify flue-cured tobacco leaf varieties. This method could better avoid the interference of environmental and human factors in the identification of tobacco leaf varieties, promoting the identification of different varieties of flue-cured tobacco leaves from qualitative to quantitative and from empirical to theoretical.

Key words: chroma values, appearance characteristics, rapid and accurate, identification, Fisher discriminant model, flue-cured, tobacco leaf varieties