低烟碱品种及栽培模式对烤烟化学成分及感官质量的影响

  目的  为研究低烟碱品种结合低烟碱栽培模式对烟碱的降低效果及其他烟叶化学成分和烟叶质量的影响。  方法  在河南省许昌市，以常规品种中烟100、低烟碱品种ITB687和超低烟碱品种NC926为材料，设置当地常规栽培模式（LCCP）和低烟碱栽培模式（LNCP）进行栽培试验。  结果  （1）不同品种在LCCP下农艺性状差异较小，而LNCP模式对其生长后期影响较大，叶片长宽比增加，上部叶面积和单叶重显著下降。（2）在LCCP下3个品种的生物碱含量差异极大，NC926上部叶和中部叶调制后烟碱含量分别为0.28%、0.21%。LNCP显著降低烟叶烟碱和总生物碱含量，但低烟碱品种在LNCP下烟碱降幅相对较小，其中NC926上部叶调制后烟碱含量降低38.03%，中部叶无显著差异；高烟碱品种采用LNCP降低幅度相对较大，其中中烟100上部叶和中部叶调制后烟碱含量分别降低44.11%、30.01%。（3）在LCCP下不同品种同一部位烤后烟的还原糖、总糖、总氮含量均表现为中烟100 > ITB697 > NC926，LNCP下烟叶总氮含量降低，上部叶还原糖、总糖含量增加，但中部叶还原糖、总糖含量降低。（4）在LCCP下不同品种中性香气成分含量以及经济性状无显著差异，LNCP下烟叶中性香气成分总量减少，香气质变差，香气量、浓度、劲头和刺激性减小，余味变淡，同时烟叶经济性状变差。  结论  通过遗传育种途径可选择性大幅降低生物碱含量，采用低烟碱栽培模式虽可使烟碱含量进一步降低，但对烟叶质量和效益会产生显著负面影响。 

Effects of low nicotine varieties and cultivation pattern on chemical components and sensory quality of flue-cured tobacco

  Objective  This paper aims to study the effects of low nicotine varieties and low nicotine cultivation pattern on chemical composition and sensory quality of flue-cured tobacco.  Methods  Culture testes were conducted using conventional variety Zhongyan 100, low nicotine variety ITB687 and ultra-low nicotine variety NC926 as materials under local conventional cultivation pattern (LCCP) and low nicotine cultivation pattern (LNCP) in Xuchang of Henan Province.  Results  (1) The difference in agronomic traits of different varieties was insignificant under LCCP, but the effect of LNCP on their later growth period was significant. (2) The alkaloid contents of the three varieties varied greatly under LCCP. The nicotine contents of the upper and middle leaves of NC926 were 0.28% and 0.21%, respectively. The contents of nicotine and total alkaloid in tobacco leaves decreased significantly under LNCP, but the degree of nicotine decrease in low-nicotine tobacco leaves was relatively small, in which the upper leaves of NC926 decreased by 38.03%, while the middle leaves showed no significant difference, the decrement of nicotine in high-nicotine leaves was relatively large under LNCP, the upper and middle leaves of Zhongyan 100 decreased by 44.11% and 30.01%, respectively. (3) The contents of reducing sugar, total sugar and total nitrogen in flue-cured tobacco leaves of different varieties at the same position can be ranked as Zhongyan 100 > ITB697 > NC926 under LNCP, which could decrease the content of total nitrogen and increase the contents of reducing sugar and total sugar in upper leaves; however, the contents of reducing sugar and total sugar in the middle leaves decreased. (4)There was no significant difference in the content of neutral aroma components and economic characters among different varieties under LCCP. Under LNCP, the total amount of neutral aroma components decreased, the sensory quality of aroma became worse, the quantity of aroma, concentration, impact and irritancy decreased, the excitability became better, the aftertaste became lighter and the economic characters of tobacco leaf became worse.  Conclusion  The alkaloid content can be reduced selectively by genetic breeding, and the nicotine content can be further reduced by low nicotine cultivation pattern, but it will have significant negative effects on the quality and benefit of tobacco leaves.