我国不同类型烟叶烟碱向降烟碱转化研究

对我国不同类型烟叶生物碱含量和烟碱向降烟碱转化的株间变异研究表明，白肋烟和沙姆逊香料烟降烟碱占总生物碱比例高，不同样品间变化幅度和变异性大，烟碱向降烟碱转化问题比较突出。单株分析表明，白肋烟JB80和TN90群体中转化株比例分别为20．0％和18．3％，且50％以上的转化株为转化率在20％以上的高转化株，烤烟转化株比例和转化程度较低。去除转化株后的纯化群体，其生物碱组成得到优化。

Conversion of nicotine to nornicotine in Chinese tobacco of different types

The alkaloid contents in Chinese tobacco of different types were measured and variations of nicotine to nornicotine conversion among different individua1plants were determined.Burley and Samsun tobacco had higher proportions of nornicotine,greater ranges and variations among different samples,indicating converter leaves with high levels of nornicotine contents were inc1uded.Ana1ysis with individual plants showed that in the populations of burley tobacco variety JB80and TN90,the percentages of converter plants were20.0%and l8.3%respective1y,and more than half of them had the high levels of nornicotine percentage of over20%.The percentage of converter plants and the degree of conversion were much lower in flue-cured tobacco.The removal of converters from the population resulted in improved alkaloid constitution in tobacco leaves.