| 4 treatments on harvesting were designed and the experiment for different harvest maturity effect on the soluble sugar and
the quality of flue-cured tobacco was carried out. The results indicated that total sugar, reduce sugar and starch gradually increased with the delay of harvest time and improvement of mature degrees, when reached a peak, the content of total sugar, reduce sugar and starch declined with the aging of tobacco and the declined of synthesis capacity. Among the four soluble sugars, the glucose was the maximum, accounted for 33%~40%; fructose followed, accounted for 32%~38%; sucrose was lower, accounted for 20%~27%; maltose was the minimum, accounted for 5%~8%. Based on comprehensive consideration of tobacco appearance quality, inherent chemical components and smoking quality, it can be concluded that when the lower leaves was transplanted after 70(±3)days, middle leaves was transplanted after 90(±4)days, upper leaves was transplanted after 125(±5)days, the treatment for harvesting was the best. The ripening features of upper 5~6 leaves in one-time harvest was that top 1th~3th leaves green yellow to yellow, the color yellowing 60%~80%, main vein whitening two-thirds, leaf yellowing near top 4th~6th leaves, 120~130 days after transplanting. |
