Abstract: This paper took Yuyan 12 as experiment material and studied the effects of spraying Mo under different nitrogen levels on physiological characteristics and quality of flue-cured tobacco. The results showed that under different nitrogen levels, spraying Mo had different results. Spraying Mo under low nitrogen levels had unconspicuous promotion role on the biomass of each growing stage & chlorophyll a, chlorophyll b, chlorophyll a +b and carotenoids contents. Spraying Mo under medium and high nitrogen levels could significantly increase dry weight of flue-cured tobacco both underground and overground, and contents of chlorophyll a, chlorophyll b, chlorophyll a +b and carotenoids in early growing stage. The increase of NR content and decrease of NO-3-N content with spraying Mo during late growing stage would become more sever along with the increase of nitrogen levels. Spraying Mo under different nitrogen levels could obviously increase Mo contents and Mo accumulation rate, which showed the rule of increasing first and then reducing during the whole growing period. Spraying Mo under low nitrogen levels could significantly increase sugar and potassium contents, reduce nicotine content, and improve coordinate ability of chemical component. Spraying Mo under medium nitrogen level, the differences of various chemical component were not distinguish. Spraying Mo under high nitrogen levels could significantly reduce the sugar(total and reduced) contents, sugar and nicotine ratio, potassium and chloride rate and significantly increase the contents of total nitrogen, nicotine and protein.

Key words: flue-cured tobacco, nitrogen level, Mo, physiological characteristics, quality

摘要： 在大田条件下，以豫烟12号为试验材料，研究了不同氮水平下施钼对烤烟生理特性和烟叶品质的影响。结果表明：不同氮水平下施钼结果不同，低氮水平下施钼对烤烟各生育期生物量及烟叶叶绿素a、叶绿素b、叶绿素a+b和类胡萝卜素含量的促进作用不明显，中氮和高氮水平下施钼能显著增加烤烟地上部和地下部干物质重及生育前期烟叶叶绿素a、叶绿素b、叶绿素a+b和类胡萝卜素的含量；施钼对生育后期烟叶NR含量的增加和NO-3-N含量的减少作用随氮水平的提高而不断增强；不同氮水平下施钼均能明显增加烟叶钼含量和钼积累速率，钼积累速率在生育期内表现出先增加后减小的规律；低氮水平下施钼对烤烟增糖降碱提钾作用显著，改善烤后烟叶化学成分的协调性，中氮水平下施钼各种化学成分差异不显著，高氮水平下施钼显著降低了烟叶总糖、还原糖含量及糖碱比、钾氯比，显著增加了总氮、烟碱、蛋白质含量。

关键词: 烤烟, 氮水平, 钼, 生理特性, 品质