机械损伤对烤烟植株氮素吸收及体内烟碱含量的影响

采用砂培和营养液培养方法,研究了在营养生长阶段切除顶芽和叶片损伤对烟株生长、体内烟碱浓度、氮浓度及吸氮量的影响。结果表明,切除顶芽导致烟株体内烟碱浓度和含量显著增加。叶片损伤也能增加体内的烟碱浓度,且损伤二次比损伤一次的效果更为明显,说明叶面损伤对烟株体内烟碱合成的影响具有累积效应。但叶面损伤对烟株体内烟碱合成的影响小于打顶处理。切除顶芽和叶面损伤对烟株体内的氮浓度及吸氮量均无显著影响,但显著提高了烟株体内单位氮素产生烟碱的能力。试验结果还表明,机械损伤刺激烟株体内烟碱的合成,烟碱增加与氮素吸收无直接关系。

Effects of mechanical wounding on nitrogen uptake and nicotine content in flue-cured tobacco plants

Effects of removal of the shoot apex and leaf wounding on nitrogen uptake and nicotine production were studied with tobacco plants grown in sand or hydroponic medium under the controlled conditions. The results showed that removal of the shoot apex resulted in significant increase in nicotine concentration in different organs and whole tobacco plants. Leaf wounding also increased nicotine concentration in tobacco leaves, and the increment caused by wounding twice was more than that caused by once. However, the effects on nicotine production caused by leaf wounding were smaller than that caused by removing the shoot apex. Removal of the shoot apex and leaf wounding did not show any influences on nitrogen uptake by plant, but increased nicotine production per unit nitrogen. The results demonstrated that mechanical wounding stimulates nicotine production, and the increase in nicotine production was not correlated with nitrogen taken up by roots.