Research on Contribution of Different Maturation with Fresh Tobacco Quality to Flue-cured Tobacco Quality.

In order to explore the influence of fresh tobacco quality indexes with different maturity on the quality of flue-cured tobacco leaves, Yujinxiang 1 was as the experimental material, and the tissue structure and contents of pigment and biochemical components in different mature degrees of leaves ( still mature, proper mature and over mature) were determined. The contribution of fresh tobacco quality indexes to the quality of flue-cured tobacco leaves was studied by partial least squares-discriminant analysis (PLS-DA). The results showed that there were significant differences in pigment content, tissue structure and biochemical components content in fresh tobacco leaves with different maturity. The quality indexes of fresh tobacco with different maturity had significant effects on the quality of flue-cured tobacco leaves. The upper and lower epidermis thickness, palisade tissue thickness, tissue ratio and ratio of carotenoid to chlorophyll had greater contributions to the quality of flue-cured tobacco. The thickness of lower epidermis and tissue ratio were negatively correlated with the appearance quality and sensory quality of flue-cured tobacco leaves, the thickness of upper epidermis and palisade tissue were positively correlated with the appearance quality and sensory quality of flue-cured tobacco leaves, and the ratio of carotenoid to chlorophyll was positively correlated with the appearance quality and negatively correlated with the sensory quality. In conclusion, there were close relationships between the quality indexes of fresh tobacco with different maturity and the quality of flue-cured tobacco, which provided a theoretical basis for the selection of judgment criteria of tobacco maturity and the improvement of flue-cured tobacco quality. [ABSTRACT FROM AUTHOR]