Effect Of Removal The Bottom Leaves And Double Tip Pruning On The Hierarchical Structure Of Flue-cured Tobacco

This study was carried out in Yanshan County of Wenshan Prefecture. The results are based on field experiments. In this paper, the effect of tobacco physical and chemical properties, yield and quality in that different numbers of removal the bottom leaves and double tip pruning, different time of removal the bottom leaves and double tip pruning, were studied. To provide the theory evidence and practical guidance for optimize configuration. The main results were as following:(1) The effect of tobacco physical and chemical properties, yield and quality was different in different numbers of removal the bottom leaves and double tip pruning. The results show that under different numbers of removal the bottom leaves and double tip pruning the maximum leaves length, maximum leaves width, single leaf weight and opening film degree is different. The yield in the same numbers of removal the bottom leaves show that do not double tip pruning is higher than removal a parietal secondary topping and removal three parietal topping. With the numbers of double tip pruning, the output value shows a rising then declining trend. Under different numbers of removal the bottom leaves and double tip pruning, the leaves’content of nicotine, total sugar, reducing sugar and total N changed obviously. With the numbers of double tip pruning, the starch of content shows a declining trend, the content of pigment in middle leaves’shows a declining then rising trend. In all treatments, the chemical composition of the treatmentat removal two bottom leaves and removal one parietal secondary topping were the most coordination.(2) Removal the bottom leaves and double tip pruning promptly that can improve the quality and yield of flue-cured tobacco. Effect of the time of removal bottom leaves on flue-cured tobacco plant height was obvious, but for the stem girth, pitch, maximum leaf width was not significant. Effect of the time of double tip pruning on the single leaf weight of upper leaves, stem ratio, the middle leaves of stem ratio and equilibrium moisture content were all obvious. Effect of the different time to removal the bottom leaves and double tip pruning on the flue-cured tobacco yield, the average of price, the proportion of first-grade and middle-grade tobacco were all significant. The proportion of first-grade and middle-grade tobacco of the treatment is that removal bottom leaves after topping and double tip pruning when pluck middle leaves were the highest. The results show that under different time of removal the bottom leaves and double tip pruning, the leaves’content of nicotine, total sugar, reducing sugar and starch is different. With delay of double tip pruning, the starch of content in the low leaf of those treatments in the same time to removal the bottom leaves declining. With delay of removal the bottom leaves, the total sugar/TN in the middle leaves shows a rising trend, total N shows a declining trend, the total N in the upper leaves shows a declining trend, the content of potassium shows a rising trend.In all of those treatments, the chemical composition of the treatment that removal two bottom leaves after seven days of topping and double tip pruning when pluck middle leaves were the most coordination.(3) Comprehensive analysis the yield, the output value and the tobacco quality in different numbers of removal the bottom leaves and double tip pruning, different time of removal the bottom leaves and double tip pruning shows that removal two bottom leaves after seven days of topping and double tip pruning one leave when pluck middle leaves was the most appropriate.