不同氮素形态及比例对烤烟长势、产量及部分品质因素的影响

Effect of different nitrogen forms and their ratio on agronomical character,economic and quality of flue-cured tobacco

在湖南浏阳,运用田间小区试验研究了硝态氮、铵态氮比例(RN)对烤烟田间长势与产量以及部分品质因素的影响.结果表明:1)RN对烤烟的农艺性状、产量、产值、均价等没有明显影响,而对烤烟的等级结构、内在化学成分含量、氮、钾、氯的吸收量有着显著影响,可以用显著的二次多项式模型或直线相关方程描述产值、均价、上等烟产量、下等烟产量等经济性状以及烟碱、总氮、钾、还原糖、氯、淀粉、挥发碱等内在化学成分的含量与铵态氮份额之间的关系;2)RN为75%:25%时,中上等烟比例、烟碱、总氮、钾、钾氯比、氮吸收量最高,挥发碱含量最低.RN为25%:75%时,挥发碱含量最高,总氮、淀粉含量最低.100%铵态氮时,还原糖、氯含量、淀粉的含量最高,碱、钾、钾氯比最低,同时显著地降低烤烟的等级结构.100%硝态氮时,总氮、钾、氯在烟叶中的含量最低,吸收总量也最少,同时产量、产值、均价也处于最低水平;3)本试验的任何RN下,烟碱、总氮、钾、氯、淀粉的含量均符合优质烟叶要求,而还原糖相反.综合考虑经济效益、养分利用率和烟叶内在化学成分的协调性,整体上RN'为54%:46%～50%:50%较好.

In Hunan Liuyang, with the field trials, the effect of ratio of nitrate nitrogen to ammonium nitrogen （RN） on agronomical character, economic and quality of flue-cured tobacco were studied. The results showed： 1） RN didn＇t influence the leaf width, leaf long, leaf area, yield, productive value and average price of flue-cured tobacco, but had significant effect on grad composing, content of chemical component and the accumulation of N, K and Cl. Within limited rang of RN, the relations between yield, average price, yield of high grad tobacco, yield of low grad tobacco, nicotin, N, reducing sugar, Cl, amylum, volatile base and the quotient of ammonium would been described by significant quadratic polynomial, and the relations between K and the quotient of ammonium conformed to negative linear equation; 2）With a RN of 75 %：25%, the value of proportion of.. high and middle grad tobacco, content of nicotin, N, K, uptake of N and K/Cl were the highest, volatile base was lowest. When RN was 25% ：75%, N and amylum were lowest, and volatile base were highest. With 100% ammonium, reducing sugar, Cl and amylum were highest, and K/Cl,nicotin and K were lowest. With 100% nitrate, the content and uptake of N, K and Cl were the lowest; 3） Any RN, the content of nicotin, N, K, Cl and amylum satisfied the demand of high quality tobacco, reducing sugar was on the other way round. Taking economy, nutrition utilization and chemical quality into consideration, the suitable RN would be 54% ：46%-50% ：50%