title: [Nitrogen uptake and allocation characteristics of flue-cured tobacco in Nanxiong tobacco-planting area of Guangdong Province].
abstract: By the method of field in situ culture and 15N isotopic tracer technique, and taking flue-cured tobacco (Nicotiana tobacum) cultivar K326 as test material, a field experiment was conducted in the Nanxiong tobacco-planting area of Guangdong Province to study the characteristics of soil nitrogen (N) mineralization, the patterns of N accumulation and allocation in tobacco plants, and the allocation of plant-absorbed fertilizer N applied in current growth season. In the study area, the amount of soil mineralized N increased with tobacco growth, peaked at 75 days after transplanting, and decreased thereafter. The soil mineralized N at each tobacco growth stage was significantly higher in the control than in the N fertilization treatment. The N accumulation in tobacco plant organs was in the order of leaf > stalk > root. Tobacco plants mainly absorbed fertilizer N at rosette stage and topping stage, and mainly absorbed soil N at mature stage. The absorbed N in tobacco whole growth period was mainly derived from soil N, and the absorbed soil N and its proportion to the total absorbed N increased evidently with extending growth stage and ascending leaf position. The fertilizer N use efficiency per plant and the residual rate and loss rate of applied fertilizer N were 30. 8%, 32. 3% , and 36. 9% , respectively. In the study area, soil N mineralization rate was relatively high, and soil N had greater effects on the quality of upper tobacco leaves. Under the application rate of 150 kg N x hm(-2), the residual amount and loss amount of applied fertilizer N were relatively high.
authors.affiliation: College of Tobacco Science, Henan Agricultural University, Zhengzhou 450002, China. yangtiezhao@126.com
authors.forename: Zhi-Xiao
authors.initials: ZX
authors.lastname: Yang
authors.forename: Hua-Bing
authors.initials: HB
authors.lastname: Liu
authors.forename: You-Song
authors.initials: YS
authors.lastname: Ke
authors.forename: Wen-Bin
authors.initials: WB
authors.lastname: Wu
authors.forename: Xiao-Quan
authors.initials: XQ
authors.lastname: Zhang
authors.forename: Miao-Wen
authors.initials: MW
authors.lastname: Qiu
authors.forename: Wei-Cai
authors.initials: WC
authors.lastname: Zhao
authors.forename: Tie-Zhao
authors.initials: TZ
authors.lastname: Yang
mesh_terms: D000042:Absorption; D002681:China; D017753:Ecosystem; D005308:Fertilizers; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism*; D012987:Soil / Q000032:analysis*; D014026:Nicotiana / Q000254:growth & development / Q000378:metabolism*
chemical_list: D005308:Fertilizers; D012987:Soil; D009584:Nitrogen