烟草化学成份含量是随生育期和烟叶不同部位而变化的。 1.蛋白质、尼古丁、总糖的变化趋势 (1) 在苗床阶段,以营养生长为中心,合成作用占絕对优势,所以蛋白质和尼古丁都是随着幼苗的生长不断地增加,总糖量由于幼苗光合面积小,且用于合成的消耗亦多,故含量低。 (2) 在大田阶段,蛋白质含量从成苗期高峰往后逐漸下降;总糖則由低变高,并均以現蕾期为一轉折点,后轉向稳定。尼古丁在成苗期出現最高峰,成熟期次之,最低点为現蕾期。 (3) 在烟叶的不同部位,尼古丁含量从下而上逐漸增加。蛋白质上部叶最高,下部叶其次,中部叶最低。总糖量以中部叶最高,上部叶其次,下部叶最低。 (4) 这些成份在烟草不同器官中含量是不同的,其中以叶为最多,随生育期变化的幅度也最大;蛋白质和尼古丁以根次之,莖最少,而总糖則是以莖次之,根最少,变幅也較小。 2.根据上述的动态表明,烟草在現蕾期以前是以营养生长为主,同化氮素能力最强,这时期必須从水肥条件滿足烟株生长的需要,以促进氮素同化过程,才能有效地提高烟草产量;从現蕾期开始,烟株已由营养生长轉向生殖生长,其生理机能也随之发生变化,已由氮素代謝为主轉为以碳素代謝为主了,以便大量制造和积累碳水化合物,这时应控制氮素同化作用,促进碳素同化作用,如改善光照条件,控制肥水的供应等都会有利于烟叶品质的提高。因此栽培烟草所采用的技术措施,要适合这个特点,才能滿足烟草生长发育的要求,才能达到提高产量和增进品质的目的。 The content of tobacco chemical composition varies with different growth stages and different parts of tobacco. 1. The trend of protein, nicotine and total sugar (1) At the stage of seedling, taking vegetative growth as the center, the synthesis takes the absolute advantage. Therefore, the protein and nicotine increase continuously with the growth of the seedling. Seedling photosynthetic area is small, and for the synthesis of consumption is also more, so the content is low. (2) During the field stage, the protein content decreased gradually from the peak of seedling stage to the later stage. The total sugar increased from low to high, both of which were turning point in the budding stage and then turned stable. Nicotine peaked in the seedling stage, followed by maturity, the lowest point for the budding period. (3) The content of nicotine in different parts of tobacco increased gradually from bottom to top. The highest protein in the upper leaves, the lower leaves followed by the lowest in the middle leaves. The highest sugar content of the middle leaves, followed by the upper leaves, the lower leaves the lowest. (4) The content of these components in different organs of tobacco is different, with the leaves as the most, with the largest changes in the growth rate range; protein and nicotine to the root of the least, while the stem is the total sugar At least, the change is smaller. 2. According to the above dynamic shows that before the budding period of tobacco is mainly vegetative growth, nitrogen assimilation ability of the strongest, this period must be from the water and fertilizer conditions to meet the needs of tobacco growth in order to promote nitrogen assimilation process, to be effective To improve tobacco production; from the budding stage, the tobacco plant has been transformed from vegetative growth to reproductive growth, its physiological function also will have changed from nitrogen metabolism to carbon-based metabolism in order to mass manufacture And the accumulation of carbohydrates, then should control the role of nitrogen assimilation and promote carbon assimilation, such as improving the lighting conditions, control of fertilizer and water supply will help improve the quality of tobacco. Therefore, the technical measures used to cultivate tobacco should be suitable for this feature to meet the requirements of tobacco growth and development in order to achieve the purpose of increasing yield and improving quality.