Impact of Topping Time, Removal Time and Number of Upper Inapplicable Leaves on the Growth, Yield and Quality of Flue-cured Tobacco

To explore the impact of topping time, upper leaf removal time and number of removed upper leaves on the growth, yield and quality of flue-cured tobacco. This study used “Zhongchuan 208” as the experimental material to set up orthogonal design L₉（3⁴）. The results showed that the topping time had a significant impact on the comprehensive quality of fluecured tobacco B2F and C3F. The upper leaf removal time had no significant impact on yield and quality. The number of removed upper leaves had a significant impact on economic traits and C3F comprehensive quality, and had a highly significant impact on B2F comprehensive quality. Overall, the comprehensive quality of flue-cured tobacco is best when topping at 7 days after budding stage, and removing 2 upper leaves at 7 d after topping.