摘除顶芽对烟株同化物和烟碱积累的影响

The Research on the Impact of Removing Tobacco Shoot Apex to the Accumulation of Photosynthate and Nicotine

[目的]研究摘除顶芽对烟株同化物和烟碱积累分配的影响。[方法]烟株培养采用砂培和营养液的方式,通过紫外分光光度法测定烟碱含量。[结果]摘除顶芽能够促进叶片、根部生长,烟株的生长具有"补偿效应",同化物增加,与对照无显著差异。打顶后第25天,处理烟株的烟碱积累量是对照烟株的2.46倍。处理5 d后烟株各叶位的烟碱浓度分布趋势即发生逆转,表现为"上高下低"。[结论]打顶能够刺激烟株根部合成烟碱,显著提高烟株烟碱积累量;烟碱的运输具有向上的极性,烟碱被大量运输至上部叶片中贮存。

[ Objective ] The influence of removing the shoot apex of tobacco to the distribution of assimilate and nicotine were studied. [ Meth- od ] The tobacco plants were cultivated with the method of sand and nutrient solution. The nicotine content was detected with ultraviolet spectro- photometry. [ Result ] The results showed that the removal of shoot apex could promote the growth of leaves and roots, the growth of tobacco ex- hibited ＂compensation effect＂. The content of assimilate was increased, and there was no significant difference with control. After removal of the shoot apex for 25 days, the nicotine accumulation of treatment tobacco plant was 2.46 times against control. In addition, nicotine has the upward polarity of transportation, after 5 days processing. [ Conclusion] This study found that removal of the shoot apex could stimulate the nic- otine synthesize in root of tobacco, improve the nicotine accumulation of tobacco plant significantly. The nicotine concentration distribution trend of each leaf was reversal and Characterized by ＂compete on low＂. The nicotine was mainly transported to the upper leaves.