利用~(15)N示踪技术,在黄壤烟区(大方县)选择了有机质含量分别为19.2 g.kg~(-1)、25.7 g.kg~(-1)、40.70 g.kg~(-1)的三种土壤类型,进行了不同土壤有机质含量和不同无机氮肥用量及施用时期对烤烟产量、地上部氮吸收分配规律和烟叶质量影响的研究,探讨了土壤有机质及土壤氮矿化对烟叶中烟碱含量和烟叶品质的影响,提出了限制黄壤烟区烟叶质量的主要原因。
三种有机质含量(低、中、高)土壤上烤烟地上部总氮、肥料氮积累于移栽后11周达到吸收积累高峰,追肥氮积累于烤烟移栽后13周达到高峰,表现氮吸收量偏高,高峰期拖后。土壤有机质含量增加,将延缓肥料氮吸收时期,整个生育期总氮积累量为92.53 N kg.hm~(-2)-95.50 Nkg.hm~(-2),来自肥料N的积累量为26.55 N kg.hm~(-2)-28.41 N kg.hm~(-2),其中来自追施氮肥的N积累量为15.45 N kg.hm~(-2)-17.11 N kg.hm~(-2)。
利用~(15)N标记法计算氮肥利用率上为27.06-32.18%,而追肥氮利用率达50.77...
【英文摘要】
The effects of soil O.M. and N fertilizer rate, applying method on tobacco leaf yield, N uptake, N partitioning, alkaloid contents and quality of flue-cured tobacco were studied by a method of ~(15)N tracing technique and field experiments conducted in three kinds of yellow soils (in Da Fang, Gui Zhou) which O.M. content were 19.2 g.kg~(-1), 25.7 g.kg~(-1), 40.70 g.kg~(-1), respectively. The significance of soil O.M. and soil N mineralization in the control of alkaloid and commercial quality were ...