Changes of Pigment Contents and Color Parameters Value with Growth Stage and their Correlation of Flue-cured Tobacco Leaves in Guizhou

In order to further explore the growth characteristics of flue-cured tobacco in Guizhou, the change and correlation analysis of plastid pigment contents and color parameter values of flue-cured tobacco leaves in the different growth stage (35 d, 75 d, 105 d) with cultivar K326, Bina1, Guiyan1, Guiyan2 and organic K326 were studied. The result showed that pigment contents and color parameter values of different cultivars reduced gradually with the exception of H* in the different growth stage of flue-cured tobacco. Bina1 had a higher pigment content in the 35 d and 105 d while Organic K326 had a lower pigment content and a bigger value in the 75 d and 105 d. L*and H* value among different cultivars were significant difference in the different growth stage. Meanwhile, b* and C* value in the 105 d were significantly higher than that in the 35 d and 75 d. Correlation between pigment content and color parameters was significant among different cultivars. Correlation coefficients between pigment content and L*, a* was in the range of 0.805 to 0.866. R² value (R²=0.915) of chlorophyll variable was the largest while R² value (R²=0.915) of carotenoid variable was the smallest. In the independent variables, regression coefficient of X_a* was the largest, and then X_H*. Compared with carotenoid, chlorophyll content had a better linear regression with color parameters value of flue-cured tobacco leaves in the growth stage. This provides theoretical foundation for improving the tobacco production level on basis of the study of the change and correlation analysis of pigment content and color parameters value in the different growth stage of tobacco leaves in Guizhou.