Relationship between Physical Characteristics and Threshing Quality of Tobacco Leaf

The relationship between the physical characteristics and threshing quality of tobacco leaf was studied through descriptive statistics,stepwise regression,partial correlation and path analysis. The results showed that there were no obvious differences in big- middle leaf( ≥12. 7 mm) rate and big- middle- small leaf( ≥6. 35 mm) rate among different tobacco varieties( or producing areas,or tobacco quality grades),but there were obvious differences in broken leaf( 3. 18 ~ 6. 35 mm) rate,broken particle( 3. 18 mm) rate,thick stalk rate and stalk content in leaf. The physical indexes had very significant correlation with big leaf( 25. 4 mm) rate,middle leaf( 12. 7 ~25. 4 mm) rate and thick stalk rate,and had a nearly significant correlation with small leaf( 6. 35 ~12. 70 mm) rate,but there was no significant correlation between the physical indexes and other threshing quality indexes. Along with the increase in the tensile force of tobacco leaf,the rates of middle leaf and small leaf increased,while the rates of big leaf and thick stalk decreased. When the length and width of tobacco leaf increased,the thick stalk rate decreased.