不同氮素形态配比对烤烟品质的影响

通过田间试验，研究了不同硝态氮(NO^-3-N)和酰胺态氮(NH2-N)配比对烤烟的农艺性状、经济性状、烟叶化学成分、评吸质量和代谢酶活性(酸性转化酶和硝酸还原酶)的影响。结果表明：施用相同氮量的前提下,提高酰胺态氮比例，烤烟的产量和产值分别提高2．5％～8．6％和1．5％～20．5％，以NO^-3-N：NH2-N=75：25和NO^-3-N：NH2-N=50：50处理效果较好，该2个处理提高烤烟均价、中等烟和上中等烟比例、总糖和还原糖含量、糖碱比、K2O含量、降低非还原糖和含氮化合物(烟碱、蛋白质、总氮)含量。烟叶评吸结果,不同处理的烟叶在香气质、综合评分等方面的变化与肥料配方中硝态氮的比例无显著相关性，其中以NO^-3-N：NH2—N=50：50处理最低。烤烟叶片中酸性转化酶和硝酸还原酶活性的变化与硝态氮比例的关系也不密切。结果表明,一定生产条件下较好的烟叶产量和产值需要适当的硝态氮比例而不是全施硝态氮，

EFFECTS OF DIFFERENT FORMULAE OF NITROGEN FORMS ON THE QUALITY OF FLUE-CURED TOBACCO

A field experiment was conducted to study the effects of different combination formulae of nitrate-N and ammonium -N on the agronomic and economic characters of flue-cured tobacco and its chemical composition and smoking assessment. The results showed that based on equal N rate, increasing the proportion of nitrate-N in the N applied improved the yield of tobacco and its output value by 2. 5%-8. 5% and 1. 5%-20. 5% , respectively. The two treatments of with the NO3- - N : NH2-N ratio being 75:25 and 50:50 gave best results in the respects of average price of the tobacco leaves, commercial grade, carbohydrate and K2O contents and sugar/nicotine ratio. They decreased the contents of non-reduced sugar and nitrogen-containing compounds. Smoking assessment showed no consistent correlation between the variation in aroma and comprehensive score of the tobacco leaves and the proportion of NO3- - N in the fertilizer formula. The correlation between the activities of acid invertase and nitrate reductase and the proportion of NO3- - N in the fertilizer formula was non-significant.